-/-

1,1 THE IMPORTANCE OF HAVING ATRANSPORT SYSTEM IN SOMEMU LTICELLU LAR ORGANISMS

Learning Outcornes:o Identify the problems that could be faced by multicellular organisms in obtaining

their cellular requirements and getting rid of thejr waste productso Suggest how these problems are overcome in multicellular organisms

Problems Faced by Multicellular Organisms in Obtaining Their Cellular Requirementsand Removing Their Waste Products

How multicellular organism overcome these problem?

1. Have sreg:.*1i:S.$..... structure to increase the s.Y.ff.9.9.9....... a.t9.9.... for the exchange of

respiration gases

2. Have t.r.-q.l$RSftsystem to get gases respiration in and out of tissue and to take excretory

waste/ urea from ihe liver to the kidney and skin

3. Have d.i.frQ.€.ty.gsystem to bring in food from surroundings into alimentary canal, digest and

absorb into small intestine. Digested food are then transported to the body cells through

blood and lymphatic system.

Unicellular organisms {Eg. Amoeba sp and Pararnecium sp)

'1, Have small size - the TSfuV is ni.9. Exchange of substances between organism ar

surrounding occurs easily

2. Body cells is directly in contact with surroundings. No need specific organ for gas

exchange.

3. Transpori system not required as gases exchange can takes place by plasma

membrane. Excretory waste are directly eliminated from cells to the surroundings

through the cell membrane

4. Does not need digestive system because food is directly taken in from surrounding

through plasma membrane by pht-9.9SJt-o.-€.'S..., then digested by intracellular enzyme

in food vacuole

1. Big size - the total surface area to volume

(TSA/V ) is d.9.e.1.9.?.f.9........

Rate of diffusion of substances inio and out

of all body cells is 1.9.S.......

2.Cells are often 19.S9.tS.-d.

far away from the external

sudace of the body

zllea-sr'*.

Sarnple Question 2 PaPer 3

The fate of gxqhqnge of SUbEtances in an organigm depends on the sr;face area that is

in contict with the surroundings. However, the amount of substances the organism

requires also depends on the volume of organism, The ability to meet these

iqqqlrgmqnts depends an the tqta! surtuce area tA vglume ratig.

Base on the above statement, design a laboratory experiment to investigate the effect oftotal suface area to volume ratio on the rate of diffusion of substances.

of

rd

lsm aI

zyme

Objective To investigate the effect of total sudace area to volume ratio on the rate ofdiffusion of subtances.

ProblemStatement

What is the effect of total surface area to volume (TSA/V) ratio on the rate ofdiffu sion of substances?

Hypothesis The larger the total surface area to volume ratio, the higher the rate of diffi]sion

of substances.

Variables MV: size of potato cubes /total surface area to volume raUo (of the potato cube)

RV: rate of diffrrsion / percentage of coloured area

FV: time taken/ volume/concentration of coloured water

Material &Apparatus

Potatoes, cslored solution/liquid //red inV filter paper

Beaker, white tile, knife, ruler and grid (transparency)lgraph paper, stop watch

Teehnique Measure and record area stain with colored solution by using grid

(transparen cy) lt calculate and record the rate of diffusion by using formula :

Rate of diffrrsion = p€rc€ohge of colored area/ time taken(o/o min-1)

4

r

1"

Procedure 1.

2.Cut the potatoes into cubes with side 1cm, 2cm and 4cm respectively.Immerse the three potato cubes into the beaker, of colored liquid for 30minutes.After 30 minutes, remove the potato cubes from the beaker, the outersurface of the cubes are dried with filter paperCut each potato cube into halfThe colored area in each cube is estimated by using grid (transparency)The percentage of eoloured area and the rate of diffi-tsion of each cube is

calculated and the results are recorded in the table.

3.

4,5.6.

ResultSizeof

cubes(cm)

Totalsurface

area(c*')

Volume(cmt)

Totalsurfacearea Ivolume(cm-1)

Percentageof coloredarea (o/o)

Rate ofdiffusion(% min-l)

1

2

3

Conclusion The larger the total surface area to volume raUo, the higher the rate of diffusionof substances

C[r

ExCreise { (Rclating size to TSAM

Examine cuboid A and B. Calculate the TSAIV of both cuboids.

Assurne that the euboids ere two organisms. Whieh oFgaRisms

obtain their cellular requirement (O2 and nutrient) and removing

their waste produets {COzand urea) easily? Why?

Answer

a

(r

p

m'm;LI

1.2 THE CIRCULATORY SYSTEM

Learning Outcomes:o State what a circulatory system iso State the three components of the circulatory system in human and animalso State the medium of transport in humans and animalso State the composition of human bloodo Explain the function of blood and haemolymph in transporto Describe the structure of human blood vesselso Explain how blood is propelled through the human circulatory systemo Explain briefly how blood pressure is regulatedo Compare and contrast the circulatory system in the following: human, fish

and amphibianso Conceptualise the circulatory system in human

Circulatory System in Humans and Animals

1. Tlle circulatory system helps organism in:

a) delivering n.:*.fi9.S.{.. and oxJ9.311...... to cells

,b) carrying .9.9*..... andw.9ft9... p.f9SY9..+.f.. away from the cells

c) protecting the body from infections

2. The circulatory system includes three components:

1'V= 54

27

A.'ti.r.tglf ..

. blood

(plasma, blood

cells and

platelets)

lnvertebrates

. h.e.::l3.llPf.h.

aodatubular heart

haemolymph

Functions as a

m.Y.f.e.}J.9l. p..Y.$P

It creates the

p.t.9.:LT.19... that

forces the b.l.?3-d...

through the blood

vessels throughout

the whole body of

the organism.

Components of circulatory system

a) Medium of transport/ BL?.9.9...

c.sPi*31i.?.*

6l@EK

1.2 THE CIRCULATORY SYSTEM

Learning Outcomes:o State what a circulatory system is

o State the three components ol the circulatory system in human and animalso State the medium of transport in humans and animalso State the composition of human bloodo Explain the function of blood and haemolymph in transporto Describe the structure of human blood vesselso Explain hbw blood is propelled through the human circulatory systemo Explain briefly how blood pressure is regulatedo Compare and contrast the circulatory system in the following: human, fish

and amphibianso Conceptualise the circulatory system in human

Circulatory System in Humans and Animals

1. Ttle circulatory system helps organism in:

a) delivering n.nt f.i?.S.{.. and o}fl9.3!?...... to cells

.b) carrying .S.g:s..... andw.gf!.9... p.*$:t9.-+.f.. awayfrom the cells

c) protecting the body from infections

2. The circulatory system includes three components:

;l":l*''

l

i

I

_lT1]3

1' A nr lflQlSn..,.....4;..

rsma, blood

s and

:elets)

lnvertebrates

. h.3.:.39.1rrr.b.

aortatubular heart

haemolymph

Functions as a

m.Y.-s.9.Y.19. !.. p. -u.$f

It creates the

p.r.9.ff.1i.9... that

forces the b.l.*S...

through the blood

vessels throughout

the whole body of

the organism.

V= 5427

-2-

Components of circulatory system

a) Medium of transport/ B!.?.9S... b) Blood vessels

c arteries

. csPll\*li.?.f....

. veins

capillariesVCINS

. blood

(plasmi

cells ar

platelet

6I@:EY

rComposition of Human Blood

. Blood is a kind connective tissue that are composed of.

D

(

Human Blood

/--\ n(,,.)}t\.-/ U

I

LLr

g

Neutrophils -

- mostabundantWBC

Monocytes *

-Origin frombone marrow

p.139.113.... sszCeliular components 45%

Le.{s.e}ls:(wBC)

Pt9.ls.l9.ts..

. Nutrients (e.g: glucose, aminoacid)

. lr,rinir"ut salts (eg .+S].,..lLpi.l..cl \'..' . '.. . .... '..,

. Dissolved qases (o*J.99lta n d.931'.P9.-3. 9: g::,ii$

. Hormones (eg: insulin)

. Waste products (eg: urea anduric acids)

. Antibody

. Plasma protein eq: albumin,g.t g.b.:l.{in.., fibrin"ogen a ndprothrombin

. Platelets arefragments of large cellsfrom the bone marrow.. They have no nucleus. They are important.inthe orocess of b19.9*..c.letti.h9.V---,tr - +(: q,,\/

| o= z-r p.

\u$ I

Ae.f.g !Tr.1 99.e,.1S1 3 0 % )Clear cytoplasmN.tl.9.!9.1.. are not lobed

Granulocytes (70%)G !:9.0.!l l3!:.. cyto plasmLobed nuclei

Lgtl.Pt'9.9J.+.9:-produceantibodies-neutralizetoxins.

3)

Eosinophils *

-controllallergicresponses

.f*nor.- *:

immobilemobile

8a- Sca'tz

Notes: . Phagocytes ='cell eater'

Differentiate Red Blood Cells and White Blood Cells

. Complete the table below:

Characteristic RBC wBc'

1. Shape a)Eryth rocytes are b.lSSl.9g.Y.* discs,

SETVES

.lncrease s!t#9.9.-e... a.trg-.S. to volume

ratio for diffusion of gases across its

plasma membrane.

b) Erythrocytes have no n.Y.9!.9.11S. to

gives space for great quantities of

h.e..s.illp.g.lI9i.n..

Leucocytes have nll.-c.t9.Y.1. uut oo

not have h s.9IP.qP.!9.f.1. f h"/"r"larger than erythrocytes and do

not have fixed shape.

2. Function . Has haemoglobin that contains iron

atom and is the site of o.LH.9S.?... and

carbon binding.

o Haemoglobin will combine with

oxygen or carbon dioxide depend on

their partial pressure and carry those

gases during respiration.

Le,v999Vtes "glg,!'g:pg?sible for the

d.9f:.?.:.-e...... of orga nisms against

diseases.

3. Diameter 8pm 10-15 pm

4. Number ofblood cell/mm3 5 million/ mm3 6000-'10000/ mm3

5. Lifespan 120 days A few days

7. Manufactured

in

B.q19... m.9.L1.9.H... ' Bone marrow (granulocytes), but

may migrate to the thymus gland or

lymph nodes for their growth and

development stages.

. L,9!P.P.l.q.* scg.t.gP. (agranulocytes)

8. Destroyed in liver and spleen By phagocytosis process

Ratio: 1 WBC:700 RBC

ellea-s,*.

Functions of Blood in Transport Fu

3) Transport of carbon dioxide. Cel I u la r resoi ration releases c.-q.L9.-o.?......

dr:e.?:{S.9..... '

Glucose + Oz ----> Energy + COz + water

. Carbon dioxide is transported from cellsto the lungs/alveolus in the form of

o hd.9.{99.9.?.. c.9.qh9391:.. ions inplasma

o b.sl..b..l.t'll.::ghs.s.n99lghiliin RBC)o Dissolves directly in the blood

plasma. When the blood reaches the lungs, the

carbon dioxide is released and. diffusesout of the blood into the aLy.igli.......

7) Transpoft of absorbed food materials. Soluble digested tood, v.itgfil.Jano mineral

are absorbed into the c.3fi.ll:.ll9f. of the villiin the small intestine. For examples:o stl*tl3.... s.YgS.l.. e.g glucoseo amino acidso water soluble vitamins ie ..Y.i*..P..o mineral salts

. Thgy are transported by the hgf$t.*. p9ltglv.g.il.. frorn slR-q.!I. i.T'.*.*ilg to the liver andthen to the heart.

. Other food materials are absorbed into the1.99.t331+..... in the villi. For examples:o fatty acids^ rrl g ceFolv Y.....r...'...1r

o vitamins A, D, E and K( fat solublevitamin)

r They are then transported by the l.{.{lPh. intothe blood circulatory system via the leftsubclavian vein.

What is transported?

From where?

To where?

For what?

1 )Transport of oX9.9.9n...... T rans port oxyg e n f rom l.9.DSf .ial.Y.99.l.Yl

to all parts of the body/ cells.r ln the lung, oxygen combines with

h99f9.-e.l.q.htn. in tne erythrocytes to formoxyhaemoglobin. Erythrocytes is thenpumped to the body tissue.

. I n tiss u e, o.r.v. h.-q. 3 :L9.s. J.9I i3. d i s soci atesinto haemoglobin and oxygen, andoxyqen is thereby supplied for c3ll.l.J.1l.r.s.*rt3]l9?.. Lung

Hb + Oz -----+ HbOhffiv.eEn

4)Transport.of excretory waste products. D93.T!.:.9f.-o.?. of excess amino acids occurs

in the 1.1Y.91"... to form urea.

. From liver urea is transported by blood tothe ki.9lSif... to be excreted.

5)Tra n sport of h.9.1.T,?.t).9f.....r Blood transports hormones produced by the

e.qC.9.91i.1.9.. g.l.?.1.S.1.... to the target organs.

. For example, insulin and g.1.T.9.-a.9Sl'1.. arecarried by blood from the pancreas to theliver.

2)Transport of water to tissuesr Water is transportqd by blood to prwide

a m ed i u m fo r b l:9.9h.9.T iS9. :.... r.e..9.!*9Ll.re)Tt| . 'n.99-u.l9l9body temperalure by distributing heat, especially

I

I from muscle & liver to other oarts of the bodv I

{n"tion"ore}

.Jt'ansoo|

./

ollea-s,,*

I

Fulnction of Haemolymph in Transport

' lr insects, the h9glng.lH.TPh. is a circulating

blood-like nutritive fluid which fills the entire

bcdy cavity called haemocoel.

2. A circulating system in insects is called oFS.?'

ci.r:.g..t].9if.t9... slr:.*3.P... because the

haemolymph

. is not confined to vessels onlY.

. bathes the tissues and internal organs directly

Nutrients from di.9.-e.f.t-e.9.. f.9.9.{.+ and h9..ll}-o..*S. diffuse from the haemotymph into the cells.

Waste products diffuse out from the cells into the haemolymph.

The haemolymph does not transport respiratory gases. Respiratory gases are transported

via the tracheal system.

Complete the table below to show where certain substances enter and leave

the blood

main blood

digestivetract

haernolymphflows into haemocoel

Bio-brain

Substance Carried from Carried to

Amino acids lle qrtl Liver

Urea

Heat Skin

Endocrine gland Target organs

lollEio- se*.I l--

Structure of Human Blood Vessels

There are three types of human blood vessels: artery, c.g.Pi]].SLy... and vern

A.n*g19....... Blood vessels that

carry oi1).9:nL:.9...

bL-o.9.3.. away from the

h.9.9f1... to all parts of

the body except

pulmonary artery.

c.-q.P.l.lSLY..,. Sites for the efS.\9!'t9..-e. ot

respiratory gdQes, nutrients and :

wastes between blood and body

cells.

. Capillary is the smallest blood

vessel which joints artery and vein.

vg.i.t...Veins transport

d.g.g.)P.91-q.-r.3.1

b1.99.9...... from all

parts of the b.*J back

to the heart except

pulmonary vein.

Human Blood Vessels

Capillary VenuleArteriole I

Artery

r* -tI

Jt--

deoxygenated biood

Different types of blood vessels

Endothelium

Lumen

Connective tissue

Smooth muscle

Elastic tissue

Cross section of typical blood vessel

Note:

. Artery branch out into smaller vessels called arterioles

r Afierioles branch to form capillaries.

. Capillary ioin with one another to form venules.

. Venules join together to form vein

ttlle;.-s, ".

3. The differences between arteries, capillaries and veins

- Pulse '. The wave oTpressure on artery due to pumping action of the heart

Characteristic Arteries Capillaries Veins

Diagram

Collagen fibre(connective tissue)

dothe

Elastic fibremuscle

Single layer ofepithelialcells

Endothelium

muscle

Direction of blood

flow

Transport blood away

from ihe h.egLt.. to the

tissuesicells

Connect

a.r*9ri9l.ff to

venules

Transport blood from the

tissues to the heart

Blood content Transport oxygenated

blood except the

pulmonary artery

Act as the sites for

eI3h9.t].9S.... of

substances with the

cell

Transport

d eoxgg8 no'te{;, tso{

except the pulmonary

vein

Wall Th.i.".S..... muscular wall One cell in

thickness (thinnest

wall)

T!:'1.'l1Sf ...... wall

Lumen size Small V.-e.|J.... s. !ll9.tl.. Large

Valve No valve (except aorta at

the base of aoda and

pulmonary artery)''

No v.9.1Y9... Valyes present along of

the vessel to prevent

back flow of blood

Blood pressure H.i9h.... (with pulses) * Lower than arteries

but higher than

veins (No pulse)

L9.::l'.... than arteries

(No pulse)

121@:8,"*.

r'

How Blood is Propelled Through the Human Circulatory System?

1. A heart, is an organ that generates the p.L9.8..{.9.f9'. to pump the blood

2. The basic structure of the human heart

\//a,,..e.e.:t.9...

Pulmonary-arterY

superiorvena cava

Pulmonaryvein

Right atriumLeft atrium

Bicuspid valve

inferiorvena cava

Chordae tendinae *

Right ventricle Left ventricle

*Chordae tendinae control theclosing of the valve and prevent thebi/tricuspid valve from turning insideout during systole ventricle*

are not controlled by the nervous system.

d) The r.r.9Jtt. p.9.TP....... forces deoxygenated blood to the lungs. The left pump forces

o.T.999.L9.t-€.9... b.19.9.9...... to other parts of the body

E

&rr.!m

W*Iineill'litiT Ii,F

F-il'qtlt r:

-:i- -

-

il\lr -

dr i*-. -\l t=. =

E*:a:/hnrswr

of ilrl,e

a) The human heart has four chambers:

. A.f*5;:-q. .. (singular, atrium) (upper chambers right and left) which receive blood

returning to the heafi.

. V.?.tlLlig.q:..... (lower chambers right and left) which pump blood out of the heart.

b) The s.eP.tY.T...... separates the right chambers from the left chambers.

c) The valves in the heart ensure that blood flows only in o.Q,9.. di.19.9.'1i.9f.. There are iq

three types of valves:

. S.g.Til-u.?.11.. wlye- the valves at the base of the aorta and pulmonary artery

o Bicuspid valve - the valve between the 19f.1... a.tl'.ig.*. and t9.fi. v.9f1.'.'.SJ'9.'.. i

. Tf.i3.lt:fi9. v.9,r,Y.9..... - the valve between the right atrium and right ventricle. il,

c) The heart is made up of c.9.fii.9.9. muscles. lt is said to be m,Y9.99L19.... because the

heart muscles able to contract and relax automatically (auto rhythm) throughout life and

6c4'>e444

lI

I

''" II

)d

rt.

tre

the

rnd

les

141

--e p;mping of the heart

b) Systole Atrium {0.1

- bicrispid'&

tricuspid

valves opened

- semilunar

valves closed

c) Systole Ventricle (0.3

- bicuspid'& tricuspid

valvesclosed-'''

- semilunar valve

opened

ffihsr an'e SAN and AVN? Mark the position of SAN and AVN on the diagram (a) above.

tne sin9..-.,q.l.fi:I.n9.L?.. 1Snf.f 1 is a specialised bundle of tissue, located in the ri9h.t.....

a*.r.iS1......... wall, near the entrance of the anterior v-9.L9...' c'lL9-...'.'..

It acts as p5.99.T:19.f...... which generate a wave of e)t9.i.t9l9I-v. irnPl.Y-s.9i... tne

impuls is then spread to atria, causing them to c.q.?IL9.tJ..... simultaneously. Hence,

blood is then forced into the v.S.$.f 1.9.}-e.f......'. (right and left)-

Further more, the impulse is then stimulates the second node atTl'.9..-.L9'lJIl9.Y!:f.'?9-d.e

(AVN) lying at the base of the ri.9.\.t..... a'i.l'r.Y.f.'........'.

lmpulses from the AVN are conducted by specialised muscle fibres called b.q.rl9.1:... .9f.

.!1f .{.... and p.\.111}1.:. fi.qf.9.f..... to the ventricular walls. This causes the

cgf,.t!S.9t9.L....... of both ventricles to pump the blood out of the heart.

The r.i9.h.t ventricle pumps the blood into the pulmonary artery, which forces the

blood to the l.$$3:.............

The 1.9.f*...... ventricle which is thicker and more mtlP.9.YlSL... than the right ventricle,

pumps the blood into the aorta which forces the blood to the whole parts of the body.

i"

l|l

E*r ain vihy the left ventricle is thickdr and more muscular than the wall of the right ventricles?

Answer: The left ventricle needs tb generate grelater p.r..e.f.).19,.1o pump blood to all. p9rti

d the bgC.V. white the right ventricle pumps blood to the l.Y.l.$f ... only. '

a) Position of SAN and

6@'>c444

a

4. What is cardiac cycle?

Answer:

Cardiac cycle is the series of events that occur during one complete heartbeat, rncluding ihe

go.n+IEelb.{systole) and r.?.13.L:tt:9.?... (diastole) of both the atria and the ventricles.

1 systole and 1 diastole equal to t hearlbeat (0.8 sec)

Therefore, the heartbeat is 75X per minute

How does the blood in the veins flow back to the heart?

. The pumping of the heart generates sufficient f.-o.19..9..... to move the blood through the

at.t9.ll.S., arterioles and capillaries. However, when the blood reaches the v.9i.?S..., the

pf9ff.'lf.e.. produced by the heart is i$.e:t$:.9Le.tl. to force it back into the hear1.

. When the body moves, the s.t3l9l9]. m$f .9.1f. around the veins contract and press on the

veins. The veins cCn*l..fi*.. and the blood pressure increases, to open the valves and

push the blood towards the heart.

Upper valve

tI

Blood flowtowards theheart

a) Muscles relaxed,

. valves closed.

5.

b) Muscles coRtract,

upper valves open

and . b.lood is forcqd

upwards, lower valve

remain closed.

c) Muscles relaxed, upper

valves closed, lower valve

opens as a result of muscle

contraction elsewhere and

blood,flows forwards. "

6. The sin9.-ai.fj.9.l. node can initiate the heartbeat on its own. But the heart rate may be

modified by certain external factors. The sJ.$f91.!.9.1J:. nerve carrying impulse to the hear

can increase the heart rate and the parasympathetic nerve can sJ.9.f... it down.

The heart rate increase when:

(a) an increase in the secretion of hormone (e.g aC.l9L9.llL9....l while a person is e.L9.it3*..,

(b) an increase in partial pressure ot c3199.?..... d1.9.T.1.9S.. in the blood. ,,tE :(c) body 1.9.'1f9.q9.t5.? is elevated. F':

7.

6.0- >cd4e

grriatory Mechanism of Blood Pressure

E,E,r€i pressure'(bp) is the f.o..r199.. of the blood exerted on the w.-q.lt.. of the

ing the *p-s.s€lS. Normal bp for an adult is 120/80 mmHg.

r;:ei'ial blood pressure is highest during ventricular s5ff.9J.9. (120 mmHg), and

dt*?.'l-4.!:. (80 mmHg) ie resting phase at the heart.

rr-e biood pressure is regulated by b9.T.9.I9.*l!9!swhich is located in the walls

a,-J cg.lStl'.9. arteries branch out from the aorta to the head"

Ssnematic diagram for regulatory mechanism of blood pressure:

'e Blood pressure stretches b.9'I9!::::ffTs(stretch-sensitive recePtors)

r lmpulses are sent to the cardiovascular

control centre in the m.9.9.Y!J.9 o.hl.?.1.9.?.1'9

. From that impulses are then sent via the

parasympathetic nerve to..tf,9.fe3rt and

bloodvessel ,:.::.j.. Decrease the heart rate

o Dilate the diameter of arteries hence

reduce the resistance

arterial blood

lowest during

of the asl.t9

rgh the

i..., the

; on the

es and

er

VE

scle

rnd

may be

,he hean

,eifed

ncrease

Normal bloodpressure

(120/80 mm Hg)

de: Blood pressure can increase because

lmel, viscosity of blood and stress.

Decrease

Normal bloodpressure

(120/80 mq Hg)

lncreaseo Baroreceptor are inhibited

. rn9.q91*9.:.. stt.*s!.9.11.:l'ot the sA

node by the sYmPathetic nerve

o This increases the contraction of the

a) csr.9.'.9.9 mT.SlSS. hence increase

in heart rate

b) s,lll9.9.fh.. mil.{.S.|9S. of the arteries,

hence decrease. the diameter

of increase in heart beat, resistance of blood

rcll&b-s*,1

,-

Gircuiatory SYstems in

. The circulatory system

lnsects, Fish, Amphibians and Humans

of large muliicellular organisms can be divided as follows:

Singlee.g flsh

!ar,'1rr

I l*llrl i

. *,,: :i'

r ,,i':

I i'

illil,arnr

> l/: l:

,r - *l-

t"* -

Completee.g human

t.q'.s9P.el.9f9e.g amphibian

Diagram

*,,&/1. I

:-

flows into haemocoel

Oxygenate'bloo

) r 'aI Gilli-capillarie 'i-+)

I roo,

J caoillari

Te

i

t

Deoxygenatedblood

Circulatory system

c.l9s..#. circulatory systemOpen circulatory sYsteme.g rnsecl

Girculatory Systems in:

lnsects - Open circulatorY system. One or more h99.ftS pump the hg.9ll|9!'l.Pf!l through the

vessels into the body cavity called h3'-€'.T9''c'9':l

. Here, materials are exchange directly between the

haemolymph and the body cells through diffusion'

e When the hearts relax, the haemolymph is drawn through

pores called of.*.J.9. (singular, ostium)back into the hearts'

Fish - Single closed circulatory system

. Heart consists of two separate chambers, an a*'T''l-o'T anO

a v.gntf.i9L9

. The d9.9.f.9S"e.1P.!$ut9.9.9"., enters the atrium and then the

ventricle.

. The ventricle pumps the blood to the c.:.fi!l::'19'{ in the

gills where gaseous exchange occurs'

r The oxygenated blood leaves the gLt'I.{.' and flows directly

to the b495., il.+S.1{9.s....

. ln the systemic capillaries, ox,99'9.Q. diffuses into the

tt:99.J.9.f.. while cgl.Lg.?. utg.*'i$.9"... diffuses out of the

tissues and into the caPillaries.

. The deoxygenated blood then flows back to the h'9'9ft""

. The blood flows through the heart only o'!"c'9' in a

complete cYcle.

ll ll&i"- Scon"lF.-

DiagramGirculatory SYstems in

hr*chihians - lncomplete double closed; *:u atory sYstem, -::: ;onsists of thr.99' chambers with two airia

;*: :^3 ventricle.

, l-:: , -, genated blood from the body is carried into

:.- = r'"i.9t.1. al.ri.'l.T while oiiJ.99.L 3l*l u'e:$.. from the

,--s ts sent to the left atrium.

r I,*r3iated blood is miXgC'. with deoxygenated

: ::: in the ventrtcle.

.--z ventricle then pumps the blood through a

-- ftonq.r-s.... cif:.'llSil.9.D s.99.t9t1..' and systemic

-

E '..'r.rrrr'

: -:-lation sYstem.

| --: blood contains *ower,levels of oxygen but is

r heart : -- cient. to meet the cellular requirements - of

=-ahibians.

1

remocoel

Gill'capillarie

)xygenatebloo

Bodvcapillari

hla nr m als'- Gom plete dou ble closed ci rculatoryst'Stem ..

r --nans have a four:chambered heart: two at'tl'9"'

a - : two vgntl.i:i.9.{...

, --e four-chambered heart pt'-e'I.9.tlt.l.'.' the mixing of

::e oxygenated and deoxygenated blood'

, --rinans have a d9.9.q19.. clp.f.?.-d. "irg.y't:'*ll

sgf't9{?"

::nsisting of the pulrllonary and systemic circulatory

*: rstems.

. ' the pulmonary circulation system, deoxygenated

: ood in the r.i9hL..- v.enltL.gl'9:' is pumped into the

p.:r.l$.9.ffiIJ. af.f9.1.'.9.s- to the l''lng.L' and oLJ'9'9'?9191'

b.i9.?:1... from the l.9nP:.' returns to the l9f!" atri'9'T'

r r the systemic circulation, blood is barried from the

h3.9.f.t. to the other parts of the body except the

l..l,?.?.:... and transported back to the heart'

. rhe blood enters the heart twice during one

:omplete cYcle.

Body capillaries

rcllf,a.-sro*I l---

a

Figure shows schematic diagram of the circulal.-,ry sysiem in human.

a) Draw Pulmonary circulatory system with

Systemic circulatory system with --€

b) Draw Oxygenated blood as

Deoxygenated blood as

Jugular veln Carotidartery

Y:..'ii:til::)V':il]//.4|11

tl

C.:flnr

Head and neck

Sub-clavian Sub-clavianvein bheiY

Pulmonary artery

Pulmonary veins

Small intestine

Renal vein Renal artery

%Hepatic vein HePatic artery

Left veniricle

5ao- >co4a

Gmnnpanison between the Circulatory System in Fish, Amphibian and Human

Similarities

Differences.

0rganisms Fish Amphibian.i. .,.j!.

Human

D,ragram of closed;rculatory sYstem

Type of circulatorYsystem

lncomplete Complete

Single D.o..9.b.1S.... i Double

C1.999S... circulatorYsystem

Closed circulatory I Closed circulatory

system I sYstem

Number of heartchambers

Number of atria

Two Three F.9.-.'.f.

o.t.-e.. Two Two

D"lumber ofventricles

One on.e.. Two

zollsi"-sr ".

t-

1.3 THE MECHANISM OF BLOOD CLOTTING

Learning Oulcomes:o Explain the necessity for blood ciotting at the site of damaged blood vessels.o Explain lhe mechanism of blood clottingo Predict the consequences of impaired blood clotting in an individual

Necessity for Blood Clotting

1. To prevent e1f99ff.1.Y.9...... bl.qgS... 1.9.9.-s.. from the body when there is a damage of the blood

vessel.

2. Maintain bl993.. p.t9f.-s.9ll to ensure proper blood circulation.

3. Prevent the entr.y of mj.9.1.99f9:$:.T.1. and foreign particles into the body through the

wound.

4. Promote wound healing.

Blood Clotting Mechanism

Platelets clump at the wound

Vitamin K

:. . Clot forms to stop further blood loss

Base on the diaqram above, describe the blood clottinq mechanism

When you get cut, blood vessels around the wound immediaiely constrict to reduce blood loss.

The platelets in the blood exposed to air become sticky and clump together to plug the wound.

Thrombokinase and other clotting factors are released by platelets.

ln the presence of c919i.Y.T. ions, thrombokinase converts prothrombin into thrombin. Prothrombin

is synthesized in the liver and requires .Y.itS.T.il..K..

. Thrombin converts soluble plasma protein, f:.!.fi.?9991. into insoluble t:.h.fi.L.

meshwork of threads over the wound.

. As the blood flows out, erythrocytes and platelets are trapped in the fjbrin fibres and a blood clot

forms. lt dries to form scab.

r When ihe wound heals, new skin is formed and the scab peels off.

form a

lnjury in blood vessels

+

ztlle,b'Sr*.

Haemophilia

e blooc

rgh the

OSS

.)5S.

nd.

rrombin

r form a

rod clot

Consequences of an lmpaired Blood Clotting Mechanism

. problems related to blood clotting include haemophilia and thrombosis.

. Haemophitia is a h9!:9.-q.:.19.f.Y.. dl:€.9S.9.9.. due to the lack of certain gene for the

production of certain clotting factors (eg: factor Vlll)

. This is an i.rllP9,J9.S. cJ.?.tfnp... m.9,9!f.tP.T. which causes serious bleeding

particularly in the joints.

. The afflicted person may die as a result of excessive bleeding from even

minor cuts and bruises because blood clotting cannot take place.

The figure shows a human heart.

a)complete the table to show whether the blood in vessels w, X, Y and

Z is oxygenated or deoxygenated, and under high or low pressure.

Blood oxygenated Blood under pressure

o*USeoqted H igh

Y ole - oxYgeogte d Low

de- ox39e oo+e sl His h

Z. orggena+eq fli9he' eL9l9**'to!"4 "+' t':'t'l:'' "state two substances in food that are believed to cause heart dis

suggest one advantage an{ one disadvantage of using the patient's own artery rather than an artery

transplanted from another person.

oo"".,"n".ls.f.".|.9i:t..l.::y3..ir.t.T9':1s'?.1..;;";;;;;n"' * i:il i: "-tr::i:f3ll) lirr:P:t rlel -a:

onfeny 4.9 ii hgs th;nner

. Sometimes a local blood clot (thrombus) is formed on the d-q:L9'9.S1'. or rough

inner wall of the artery, for example deposition of cholestrol. This may cause

blockage of the artery, a condition known as t.t't9.P.9'*.1.:.

. When the thrombus drslodges and is carried away by blood circulation, it is

known as an e:T.f9l.Y.{.... The embolus may be trapped in a small artery where

it btocks the blood flow. This condition is called e.11.\9!if.T....

. lf the thrombosis occurs in coronary artery ( vessel that carries blood to the

heart) the supply of o+.V.99.1...,. and nutrients to the heart muscles is cut off,

hence causes h,?.9:.1.. af!:9SI....

Bio-brain:

wqlls +hQn qn orlerJ'

1.4 THE LYMPHATIC SYSTEM

{1)

. When the blood flows from arteries into

csp.tlqgti** there is higher tr.u9f.gS.t91lg..

pressure at the.arterial end of the capillaries.

. This high pressure forces some plS-".1?.9".

to pass through the. capillary walls into the

i nt S lc.9.tl y.|.9.1. s p.S. 9.9f.. . .. between the cel|s.

Learning Outcomes:o Describe the formation of interstltial fluido State the composition of interstitial fluido State the importance of interstitial fluido Describe the fate of interstitial fluido Describe the structure of the lymphatic system

o Explain how the lymphatic system complements the circulatory system

o Compare the contents of blood, interstitial fluid and lymph

o predict whatwill happen if the inter:stitjal fluid fail-s to return to the.circulatory system

o Conceptualise the relationship between the lymphatic system and the circulatory system

Formation of the lnterstitial Fluid and Lymph

(2)

. Once the fluid leaves the capillary

walls, it is called i.?.t9!'.fiit'l:1....'

or tisf 113... f.l.Y::9. rhe

interstitial fluid fills the spaces

between the cells and constantlY

t bathes the cells.

I

(3). .90% Qf the

interstitial fluid

diffuses back into

blood capillary

. lAok.of the interstitial fluid that

has not been r.9.iF.fp.':b.9.{.... into

the bloodstream goes into the

tp. PR!'...... c9.?i.rlsllsl once

. inside ,t[9, Jymp,,h capillaries, the

fluid is knowr as l.Y.TP.h -

nl@:8,*"

rrTme{rs-iitlaI Fluid

Oomposition of the lnterstitial Fluid

. --: composition of the lnterstitial

'u C is similar to the blood Plasma

axcept there is no erythrocYtes,

pr*1.9.19.-+.1. and plasma protein

'inolecules (albumin, globulin and

'brinogen).

o-eucocytes especially phagocytes

can pass through the capillary wall

and can be present in the interstitial

iuid.

lmportarice of the lnterstitial Fluid

" lnterstitial fluid is important because

o lt forms the illt*.fl?.?J eItYI.t-b.?-S'9'?.f'. of

the body

o lt, ba"thes the cells and supplies them

with o.'fH9..9P... and nutrients .which

diffuse from the b1.q99....... through the

intgLs*:i-".t t.ly,i*... into the cells.

o Excretory wflitS. p.*S.Y.9.ti (carbon

dioxide and ureq) di.t8.+.fi o.-ql' of the

cells into the interstitial fluid.

;rinto

I

i::l'^"1

__l

Fate of the lnterstitial Fluid

. Approximately 90o/o of the interstitial fluid ftows back into the v.-e.FP.Y.f...

capillary system where the hydrostatic pressure is low'

r The remaining 10% of the interstitial fluid enters the

called lsra.P.l'....,

o Lymphatic capillaries from all parts of the body converge to form lymphatlc vessel-

r lt is clear now that lymph also originates from blood plasma. lt has almost the same

composition as the interstitial fluid which lack of erythroc$es, platelet and plasma

r lf excess interstitial fluids unable to return to the blood circulatory system, it

accumulate and cause tissue swelling known as o'9.*.9'T'9"".'"'

lnterstitial Fluid

2al@:8,-*,

F

Lymphatic System

a) Structure of the Lymphatic $ystem

. The lymphatic system is a oft€-w9.$. s,9S.t9{?... consisting of a

cstill.?.r. i.es., u$.p.1.9*i 1.. v.e.{f fl .1,.. a n d l.Y,*P h.., n.:i Pf ..

ill

1I}

I

\\

t

'l'il

lrI lJi1\

i\;r. I,\t/\ t,t(ll'l t

Enlargement of Lymph node

a\

t,^{l'lvi1r1t\]'\\,/.

a one-way valves

Lymphatic vessels

. The lymph capillaries are bJr'.F.9...-en.9.9.d-

t.'tb.g.q.. located in the spaces between the

cells.

The interstitial fluid that l-tas 'not

been

reabsorbed into the bloodstream goes into

the' ts.flPh. '69ni!l9l'.igf. Once inside the

lymph capillaries, the fluid is known as

lfmP.h... Lymph is the colourless fluid found

i n the I x:Tlr.b.:ll:9.... v.gf.i.9LL.

r Lymph capillaries converge into larger

lymphatic vessels.

r Lymphatic vessels form two main lymphatic

ducf -right lymphatic duct and thoracic duct

r Located at intervals along the lymphatic

vessels are lymph nodes. The lymph nodes

produce lrnp.!'-g.s*r..19-s. tfrat involve in the body

defence against infections.

r Hence lymph contains a higher number of

lymphocytes than blood.

Valveo Within the lymphatic vessels are one-way

valves to ensure the c9'f1l:r.)l-c.-'1.9.. f.19.9 of the

lymph to prevent the b.9.95f J.9* of the lymph.

8' - Seo'rz

-___lcrc I

il'l

t)claviann

! Tiie Relationship between the Lymphatic System aitd Circulatory System

: i-,,mph is returned to the circulatory system via the

r"h.9r.q.9i9 dl{9.tand the ri.ghL lJ.Pnh:i.l9 d'Y.g.t

r -:e vessels from the l9f.t sj'9.9.. of the body (the

a, mentary canal and the right slde of the lower part

:: the body) flow into the thoracic duct. The'thoraeic'

iuct is the largest lymphatic vessel in the body that

carries lymph to the l.gft s'Y.f.:1.-o.:11". v.-e.!'l.. back

,nto the b1.9.o.i.{}f '?'9.m

. The right lymphatic duct transport lymph from the-tTi,+g. of the head and chest into the r.i9.b.f

s.itb.9.l?.Y,l3l v.ci.tr..

Lung

LymphaticSystem

Blood CirculatorYSystem

\iI

. The movement of lymph along lymphatic vesselis aided by hydrostatic pressure, one way

valve, contraction of surrounding skeleton muscles and respiratory movement squeeze the

vessels.

Complete the diagram below-

Blood capillaries

V

t nt-€.i$.tj.t-ql f t .,{.i9.

Diagram shows the Relationship between the Lymphatic system and circulatory system

Right subclavian veinLeft subclavian vein

Lflf.Q.Ph. v9*iSll..Lymph capillaries

zallEa-sco*t F-.#

r

Role of the Lymphatic System iri Transport

. Coilects the i.r.,.t.9:fi.1:.1.. t.l:f J.i. and returns it to the blood circulatory system.

" F.9ii9 ,agiC..", g1999.191....... and fat-soluble vitamins are absorbedinte through

l.-q.99.?,|.{, in villus and transported to the blood circulatory system.

. The LYaPh n99.9.s.. produces phagocytes and lymphocytes.

(i) Phagocytes engulf and destroy foreign particles.

(ii) Lyrnphocytes produce anil..5.9$.i9f.. which aid in the destruction of pathogens

and the neutralization of toxins. Hence, lymph nodes filter out pathogens and the

foreign particles and protects our body from diseases.

Compare the contents of blood, interstitial fluid and lymph

'mg

tu

B!.ood lnterstitialfluid

*WBC may escape frorn blood capillary and goes into intercellular space

due to flexible shape.

Composition

. Plasma without

p1.3.f.s.9. p.qe.L?I1.,

erythrocytes and

p.ts.L9l?tl

. More fatty

substances and a

higher number of

lymphocytes

produced by the

lymph nodes.

Plasma without

plasma protein,

and cellular

component except

WBC-

. P.lSf.lPS. andcellular component(wBC, RBC,platelets)

zzllSa-s,'*.

ROLE OF CIRCULATORY SYSTEIS IN THE BODY'S DEFENGE SYSTEMrgh

3ns

the

Learning Outcomes:. stute another function of the circuiatory system besides transporl.

: Identify the the body's three lines of defence mechanisms'

: Describe the process of phagocytosis.

:, State the meaning of antigeii and the antibdy.

iil'dI s Defence Mechanisms

ies oes transport function, our circulatory system also defends the body against disease abolition

:"' :*e disease-causing microorganisms or pathoqens.

: : -" aodies have three lines of defence against pathogens:

: First line of defence - prevention of pathogens entering the body'

:, Second line of defence - killing the pathogens that entered our body by action of

Phasocvtic white blood cells.

: Third line of defence - killing the pathogens by means of antibodv actions.

First Line of Defence

al Prevention of pathogens entering the body

by mean of physical and chemical barriers

DJ A non-spesific defence, that is never

differentiate among various type of

pathogens. This includes:

Skin

n As a physicalbarrier, skin is made up

of a dead keratinised laYer, tough

enough for pathogens to penetrate.

. lf thgre is a scratch or cut, the blood

clots to sealthe wound and avoids

infections.

. Also acts as chemical barrier as it

seeretes sweat whieh eontains salt.

Sebaceous glands Produce sebum

whieh esntains aeid and oil. All these

substances are unfavourable for

growth of microorganisms.

' Sweat also contains-.lysc@ which

destroys Pathogens.

^o

Tears and Saliva

. Contain lvqozv-{nes

which protect the eYes

and rnouth from

pathogen invasion.

Gastric juice in stomach

" Contain hvdrochloric

acid which dqstroYs

most pathogens in

foods and drinks taken-

Mucous membranes

. Secrete mucus in nasal cavitY and

trachea to trap the dust particles and

spores

. The cilia in the respiratory track sweep

the irapped particles to the pharynx and

stimulates sneeze or cough to expel out

the paihogens.

,'

Second Line of Defence

(a) The killing action brought by some of the white blood cells like neutrophil and monocvte.

They are calted phaqocvtes and the process is phaqocytosis

(b) lt is also a non-specific defence.

(c) Phagocytosis occur when pathogens get through the first line of defence, Phagocytes move

the infected area due to the stimulation by chemicals released by damaged cells, example

skin.

(d) The steps involved in phagocytosis by a phagocyte e,g. Neutrophil

. Useful product of

digestion is then

absorhed and

assimilated by

phagocyte

Complete the diagram above.

(e) Sometimes the phagocytes are killed by toxins produced by the pathogens.

(f) Dead bacteria, tissue cells anci phagocyies may accumulate to form pus at the site of injury

Third Line of Defence

(a) The third line of defence in the body is antibodv.

(b) Antibody is a kind of protein released by lymphocyte in response to the presence of fore

substance, called antiqen in our body-

(c) Lymphocytes are white blood cells found in lvmph nodes and in the blood circulatory systr

There are two types of lymphocytes, Bjvmphocvte that secretes antibodies and Tlvmphoc,

that helps B-lymphocyte in antibody production.

(d) An antigen is a subtance (usually protein) normally found on the outer surface of pathog

Different types of pathogen act as different types of antigen.

29

lEe.

:es move

)xample

rf injury.

of fore

tory systt

lvmphoc'

f pathog

---.::ci line of defence is a sF9.9.i.f:.9... O.g.f.g.1:9..... because when a specific antigeir

- .-:s the bociy, lymphocyte rs stimulated and produces specific antibody to destroy

-..= scecific antigens.

--: -esponse is known as i.T.P.Y.IS....... r.9i.P.911.f9.... because it resists ihe body from

: ; "- -:jens or diseases.

--:-an rnfection, some lymphocytes remain in ihe body as m'9'T.9.|X"...-' c'9ll-{-'.. which

* = " ast for several months or years. This memory cells help to defend the body against

-:,. infection by the same aniigen. During this period, someone is said to be

-T:1.!.9.9. .. for that particular disease.

--=-:fore, the word 'immunitl refers to the g|l.t'iY..9.t.:1..919.:.1:-"'T..t9..9.:tsl9'.t::tl

a e 3 ! lt.{. . ir.f .9.q1 i 9.1. .h .9 . .P.: i. f,.g.e.9.rls. . .

-ai is the mechanism used by antibodies to destroy antigen?

. Antibody b.in,i9........ to the specific antigen binding site

. hence, i.aSStiY.g.t9.i.... antigen by several ways

Ways Explanation Diagram

r.l.e:$r9lif.31l9l

)isintegration

re:J:1i.?.11e.!

oPs..?.lHs-+.e?.

. Antibody called antlj9Iit.'..coats

the bacierial toxin or viral

binding sites and neutralize it.Bacteriurn

Antibody called l.9.fj.l.l.

binds to the antigen causing

antigen to rupture or disintegrate. -

Bacterium

Agglutinins are antibodies that bind

to pathogens cause to clumP

together and stoP their movement

and stimulate phagocYtosts.

Antigenrnolecules

Opsonins modifies antigen bY

attaches itself to the bacteria

surface and thus stimulates

^ hqgaCJtosist,,,..'..

Y = Antibody molecule

Learning Outcomes:o State the meaning of immunit and immunization'

o Relate antigen and antibody to immunity to immunity'

o Name and give examples of various types of immunlty'

Types of lmmunitY

1. lmmunity is the body resistance to p9.th.o.?.9lll which cause a specific disease.

2. lmmunity depends on the presence of lymphocytes and the production of anij.P.93jli.,.

whjch give a specific immune response'

3. There

Graph

lrlll

I

$

Time (weeks)

are various tYPes of tmmunitY:

(a) Natural Active lmmunitY

. When a person is attacked by a kind of

pathogens, antigen of the pathogens

stim ulate an i lT.PlllS. . ... r.9. 9.P'?.1S.1.'.'

. L.9lLP.h9:.Y.tSs release antibodies into

the blood stream to destroy pathogens'

r After the person recovers from the

infection, some lymphocyte remain as

m.9.t119.t9.... c9!!1..... in the bodv

. During second infection, this memory

cell initiate rapid immune response to

produce more antibodies and the the

person becomes i'11lT.Y.?.g.' to that

particular disease.

. E.g: Chicken pox virus, measles virus'

o

v,€)

o.o

(Ec+3o>ol:(E-O

o-

O-o

vlls,b- s,,,1

as

--ldies

I

sI

munitylevel

-f---->I)

Types Graph

s,.t.''cial Active lmmunity

. l::ained after a person is given (orally

:- :y injection) a v.qPSi.A9.. before the

-::ction occur.

c -i process of making immunity by

-:'cducing a vaccine is called

n.T.Y.ti.{lt:911....

r I ',,s661pg is a suspension of killed or

n,'. 9-a.t?.1S9. antigens (bacteria/viruses)

"".rich is not harmful to the person.

. ."accine stimulates l.9P.P.l3S..).tSl in tne

::dy to produce antibodies that capable

:: destroy living antigens which causes

: sease.

=rerefore, for the coming invasion of the

:athogenic microorganisms, the body is

: b I e to d estroy them i.fl .T.9.1j:.L91.Y. . . . ...

:ecause it already has the antibody.

Booster dose (2tu)

stimulates a faster and

longer lasting

resp0nse.

lmmunity level

1"t vaccination 2'd vaccination Time (weeks)

'o

-o

r!trsi]o>6S(g_O

E60r-o9xo()-o

+

1" dose usuallyinduces a slow andshorter lasting

. Finally, we can say that the body has

acquired immunity throug h v.qS:j.qSJi9l.

. Examples. BCG vaccine againsi

tuberculosis. Salk vaccine against

^ oliorngel;+iSP. "..'

\aturally Passive immunity

. Obtained from the mother either across

:he p.t9.9.9.?t9..... to the foetus or

ihrough the mother's milk to the infants.

r ff foetus received several type of

maternal antibodies during pregnancy

o Early mother's milk or c.:l.9flLY*... also

contain antibodies.

. All these antibodies protect the baby in the

first few months after birth.

. Examples . Antibodies to avoid pneumonia

and common cold.

Artificial Passive lmmunity

. Obtained through injection of a F.?.f.Y.T..

wh ich co nta i ns s P.t9jf. iS. . .. a I)l!.9 9.L i 9.f.

zzllgi"-sr"*.

Graph

This serum containing antibodies is

prepared from blood of human or other

animals, for example horse.

The ready made antibodies is given to

the person who needs the antibodies

urgently like t,t:g.'{-e.!!9L:.. or the patient

who are seriously ill. E.g: t,gtgll)l:...,. ,

botulinum and s.QSF.9.... b.itgf.....

The injection gives a quick immunity but

cannot last longer because this foreign

antibodies breakdown in the body and

are not r.9.Pt3.i.9.1

Examples: Anti-tetanus, rabies anddiphtheria

d)-c

.=o.9:oo-oc:

o>ol:

o_Xo()-o

Differences between active and passive immunity

Aspect Atrificial

Active immunity

Artificial

Passive immunity

1. Type of injection V.9.9S.:n9..... contatning dead

or weakened pathogen.

S.9.1.Y.T,..... containing specrfic

antibodies.

2. Time of injection Before a person is infected

with a disease.

At the time when a Person ls

rnfected or high risk of getting

the disease.

3, Time taken to achieve

lmmunity

Body needs time to synthesise

antibodies.

Ready made antibodies give

i.l?.T91i: L?..... i.n.p.v. ril. H.. .

4. Duration of immunity L.?.t.9....,. lasting of immunity lasting of immunity

5. Necessity of booster

I

oose

Needed for certain diseases

like hepatitis B because the

first injection usually induces a

slow and low level of antibody.

Normally not needed.

First injection offers sufficien

immunity

zzllg,a- s,*z

*ear-ning Outcomes:Slate the effects of the human immunodeficiency virus (HiV) on the body's

c:lence mechanisn^s.Describe the transmlssion of HIV'

: suggest ways to prevent the spread of Acquired Immune Deficiency

Syndrome (AIDS).

-.:quired

level

J Specli:

lerson -:

rf gettir;

lies gi',i

,ni.t I

-1, -:=-:, HIVvirus

The Effects of HIV

feks)

d

n' :rril;:{: :.e central nervous system

il'-r -::3r r..991!1., in the body's

: S,'Stem.

' -'q :,:- --cef fs are essential to activate

! :€ Ix. '.. .. ', lymphocyte in antibody

-- ^n

* * , -r3js B - 10 years of in9:tp'9.119.n

r',:- : I :e'ore the sYmPtom aPPears.

* -": -*une system of infected person

r, ":: -a ,l becomes weakened and

r'*'=-::ress against many pathogens'

- : € cf.9.99.9f.. in function of central

" : - : ,s system followed bY bodY

'* e 9.h1..... loss.

* :,i-i-?ily death occurs. The patient

:,"== :rct die from AIDS itself but from

:rmunity s.9.eg.a.{31^.Y. infections such as

-onia and meningitis, tuberculosis,

infections or certain forms of

:ike Kaposi's sarcoma.

ty

sufficieii

HiV virus

Transmission Methods

. HIV only survive in body fluid such

such as s3.99.1......, blood and

v.9.?!n91.... fluid.

. Therefore, HIV can be transmitted

through s.3.LY.?.1'.. intercourse, blood

t.1.9.?.qf)'!.ii.qf...... or injection with

contaminated needle used to inlect

drugs.

. HIV infected pregnant mother can

pass HIV to her babY through

p.{9.99}.13.... or br.9.3.:t.T1If.. "'.... HIV cannot be spread bY touching,

sharing of food or through the use of

public torlets.

Prevention

. Avoid i.U.9.9:1."...' s.91"'..'

. Using c.9!];d.9.T.1.. during copulation.

. Using only s9.1-".?19.9.. otooo in blood

transfusion.

. Educational programs for p.1Llit"""

ancsS!r,9.? c.|i1.1.f91....".

s+ll€,n-s,,*.

7

1.5 APPRECIATING A HEALTHY CARDIOVASCULAR SYSTEM

Card iovascular diseaseo.i:.erlsl ...ffiodcircutarorysystemExamples: Hypertension, R.Q.91.1.9.,.., c.g.qg.q9fy...thL?.T.q:fi.l, nrtS.li9.:.:!:.1"..fi:.

Risk factors: L..... s..........., age and family history

CCIUSCS

Lumen

Cross-section artery

The heart has topump harder

1.

L.

3.

lt-

Ititllliurrulltr

Ull

iihuN

Coronaryartery

Notes : Coronary artery is aspeciaiised blood vessel to supplyoxygen and nutrients to the heart.

Severe

Learning Outcomes:o Select and practice sultable ways to malntain a healthy cardiovascular system

blood

fr

I CardiovascularDisorders

Blood clot may occur in

narrow coronary artery

"Angina(chest pain)

"Heart attack(Miocardiai infarciion)

6@- >c442

THE TRANSPORT OF SUBSTANCES IN PLANTST

€ nos;s

Learning Outcomes:o slate the necesslty for transport of substances ln plants.

o Identify the vascular tissue in the stem, root and leaf'

o state the role of vascular tissue in the transporl of substances'

o Describe the structure of vascular tissue'

o Relate the structure of xylem to transport'

o Relate the structure of phloem to transport

o Predlct the effect of removlng a ring of phloem tissues from a plant'

f,1il1,*.*:essity for Transport of Substances in Plants

, : a^is absorb wgfit..... and ml.?.9.1-a!...... i.9.?.:....... from the soil to all parts of the body'

: ,,3.3r- fleeded by ptants to carry out p.\919:.-5,?ti'.S.ll acts as a solvent and rSSgt3t'f" in

-; cell metabolisms'

t, ,* n "eral ions are,.required for healthy growth and d.9.I'?-19t.T.9'f'1" ""'r 3-all multicellular plants such as m9.S.{9f.,.. and liy'9'l:.qLtshave a large TSAA/ ratio and a

s ir.g,rL........ distance for diffusion of substances. Therefore, they do not requtre transport

:-. -r:em.

i -:,,vever, in large flowering plants, conifers and ferns, they have a s'P'9'l\ TSAJV

-:to and gf.9-qt9.f.-.... distance for a diffusion of substances. Hence, they require an

-:ernal transport system in their body'

ll rscular Tissues in Plant

' ransportation of substances in plant is carried out by v'9'eS'I!':'1"" t'i:'f'Y':""""

I -here are two types.of vascular tissue: xJl9f..-... and p.b)'93T""""' tissues'

i o.,item transports w.9L9!1...,.. and di.qf'?l'Y9-9... m!'lr.9l9'!"" s'?'t't'l"""' absorbed by roots

:: the upper parts of the plants. lt also gives s.Y.P.P.gtl'.-.' to the plant'

I :hioem iransports o.f.93Iti9.....,. s.g.l:iS.lStl' synthesized by the leaves during

p,f.9t9.{.Ytt}.9.ii:.. to other parts of the plants'

: I agram 1 shows the locations of vascular tissues in a dicotyledonous plant'

--la;,;""1

I)

il;-l

lll

6@'>aa44

F:

(a) Cross-secticn of a Leaf

Cuticle

Xylem

Phloem

/,/( (b) Cross-section

of a Stem

Epidermis

s.l9.T.:

. Contain vascular tissues thatare continuous with those in

the stem and root.

One-celled thick with cuticlelayer outside

Has l .?.11i.'.9Jlfor respi ration.

Consists of c.?ll:tSh9.T.9cells in outer region andp.9.'.9.1.?1. LT.9... cells in tnnerregion

Provides support to the stem.

.r ench$rhoConsists of large P.9....^^il^LUil5. i

F..9:1..... storage

Vascularbundle

Arranged in thearound the pith.

Xylem and phloem separatedby c.?.TFI.YS...... tissue

Root hair A specialised eP.i.*T.T3l, cell

lncrease the s.Y!T9,9Sa.f93..... for water absorption.

Epidermis Does not have c.Y.{i.9.1.9........

Absorbs water and i9.?.f..........from soil.

Endoderm Single layer of cells

ricycle Consists of sg.l.9.f.l.?l)lCItissuewhich provide mechanicalsupport to the root

Consists of vascular tissue andpericycle

Xylem radiates from the centreforming si.9f....... shape.

o Phloem fills the area betweenxylem.

(b) Cross-sectionof a Root

Phloem

Diagram 1

" Wax substance to reduce\^, qre.l. I oSS

' Vascular bundle in vein.

,trt'

,i't)

1

\

6.4- >c444

$1,r)",:;*-e of Vascular Tissue Related to the Transport

PHLOEM

educe

>s thatose in

XYLEM

)I" :r' t.;.i.., parenchyma ano t.ih.1.9.......

Phloem

Also consists of 4 types of cells, i.e. sieve tube,

cs.q1P.Lli9.l.... c.3.\t...,, fibre and parenchyma.

1. Sieve tube

. Cylindrical in shape, consisting of elongated

sJ,?.Y.9..... c.9.!1....., arranged end to end.

. The end wall of each cell are perforated to form

si.9L9..... p.t:1S.... and allow food

substances such as s.:t9.Pf9.. and ani.1.9...

a.9.i9..... to pass from one cell to another.

. The sieve tube is a living cell but during

maturation, many organelle including nucleus

disintegrates.

. There is a ihin layer of c.p.Lq.R.!9J.T.. lining the

cellulose wall of sieve tube.

Companion cell

. Normal cellwith nucleus, cytoplasm and many

mitochondria.

. They are adjacent

the sieve cell.

. lt provides ATP to

the sieve tube.

Parenchyma and fibre.

. Parenchyma cells store food

. Fibres provide support.

Thin cytoplasm

Companion cell

Sieve tubes ICompanion cett

IFibre )I=t

cuticle

ltion.

chg rn o

r andr inner

stem.

ch$rno

P.9......

laratec

jr :- ',,eSsel

r f - ?iti vessels are long, hollow and

: er.1i l.Y.?)'l:....... tubes.

. D F..q.9..... c.9J19...., no protoplasm

: - :asier the flow of water.

r -3 ceil walls are strengthened by

r,?.lll., deposited in various patterns

,- : gives m.g.eI-q.LiLll...... support.

. *-: cell wall with numerous hole or

e.*,., to allow w.?.t€.T.. and mineral

::ss side way between the cells.

-"::heid i

r - sc dead cells and hollow but more

:nger and smaller than xYlem

^^^^l. =55Ut.

. tcrnted end and pitted.

LS of tracheid

:::anchyma and fibres

. =arenchyma stores food.

. =ibres provide support.

/,\\dtJ*

ll,11d) I:l$

ffiil1lJ\/

ll. cell\6

;il;;and closely related to with

help the food transPort in

Sieve plate

ItQ.r^^..^.. Ll55UC

chanical

sue and

o_o

=o)

.qU)

r centre3.

between

Xylem vessel(Patterns of 4

lignin deposited)

ffiI=ffil'. I [,^.] l€

HEH

6c4- >c442

Pit spiral r!

1.8 TRANSPORT OF SUBSTANCES IN PLANTS

Learning Outcomes:o State what translocation is,

o Explain the importance of translocation in plants'

o Describe the process of transpiration.o Explain the importance of transpiration,o Describe the pathway of waler from the soil to the leaves

o State external conditions affeciing transpirationo Design experiments to study factors affecting the rate of transpiralion

o fxpliin the role of cohesion and adhesion of water in the movement of water in plants.

o Conceptualise the transport mechanism in plants'

Transport of Orga n ic Substances (Translocation)

1. Definition : Translocation is a transport of soluble o.q9?.Li9..... s-'l!.fJ:l*f' sucn as sucrose

anO a.!'li!.|9..... a.Si$...... from the leaves to other parts of the plants.

Translocation is a two directional transport, uf.Y-q.19.... and dsl.Y.L.*.919". ano occurs in

ihe s.r1,P.Y.9,..., t.Yp.-e...." of the phloem tissue.

2. The importance of translocation : to enable the product of photosynthesis moves from the

leaves to the:

(a) G.q:.*.t.\.. region such as shoots, roots, and young fruits'

(b) Storage organs like t.'Y!.9.1.'...

(c) Other parts of the planis to be a raw materialfor cell r.9.Lfll3lP-l.'...

3. To show the role of phloem . Bark Ringing Experiment (Practical Book:Experiment 1.7 pS.15)

Method Result Explanation

(a) Choose a healthy small branch of a

tree.

(b) By using a knife, remove a

complete ring of bark, about 2cm

length.

(c) Leave it for one month.

The tissue above

the ring swell uP,

whereas the one

below the ring

withers.

J he trssue removeo togelner

wiih the bark is p.t:J.?.9.T......

This disrupts the flow of

organic substances from the

leaves down to the root.

Accumulation of these

substances causes a

s.Y.1.ll.'.?.9. above the ring.

The leaves of small branch

do lot wilt because the

x.H!.9.T..... has not been

removed. So, uPward flow of

water is not disruPted.

(a)

(b)

{c)

(d)

After one month

3sllgb-s,*1

I

--ansport of Water and Mineral lons

' ::cm the soil, water enters the root by of.3.9.liL. whereas mineral ions by agliy9t.fq.l.f Pgfl

- -.,e presence of root hairs increase the siilflS.9.... a.f9.1...... for absorption.

iucrose

;curs in

r the

1.15)

logetherem

flow of

irom the

rot.

these

u5d

: rrng.

I branch

use the

oi been

'd flow of

d.

-re movement of water from the root

:: the leaves is aided by three factors

a) Root pressure

c) Capillarity ( capillary action )

c) Transpirationalpull

]-EAVES

(c) TranspirationalPull

. During the day, water eY93'?'tSI9': from the

mesophyll cells into ihe intercellular space in

the leaves.

. From here, the water vapour diffuses to the

surrounding air through the stoma.

. The loss of water from the leaves to the

atmosphere is called t.nL:.f.in.ll.gf ..

. Transpiration in ihe leaves pull up the waier

from the soil, a force called t.t)Sl.fi.fglign p.y.l..

r[ET@t

(b) Capillary Action

. Capiltary action is a combination

force of c 9..hSti?.1 a no a *.h.e..ii-o.1,

which enable the water move uP

along the narrow xylem vessel.

. Cgh.9.lfiY.9. force is the attraction

of one molecule to other molecule

of water.

. Meanwhile, ad.b3.i1.Y.9... force is

the attraction between water

molecules and the wall of xYlem

vessel.

. Therefore, xylem vessel forms a

continuous column of water from

root through the stem to the

leaves.

HzO **"Stonra

Xylenrvessel

(a) Root Pressure

. The surrounding soil water is h.9P.9.'13.t].*... to the cell sap of root hair because ii contains

salt, s.9.99.1 and amino acid.

. Therefore, water diffuses into root hair by o.9.T.?.f.'t""

The entry of water into root hair diiutes its cell sap to become hypotonic to the a$'9.9.91'tcells.

The water moves again to the next cell untrl it crosses the c.9.f.t.9f ...... tissue by osmosis.

This water concentration gradient existed in the cortex creates a force called r,9'9'f".'."

p.{9.*.Y.1.1....... to push water into xyiem.

ROOT

Encloclent

t----------.H

6@- >c442

1.9 Water Loss from the Plants (Transpiration)

1. Definition: The loss of water in the form of w9t9f ... v.9t99.f. from a plant to the atmosphere.

Atmost (99%) of the water taken by ptants is e.Y3 f 9.i9.n9.. by transpiration, only 1% is used

for p.ti9.tliy.lfl.q:.i:.. and io remain t"Y'l:J.1""""

2. About 90% of transpiration iakes place through the s.*1.?.t3. .....,|oh through the cllll3.l9

and 5% evapoiated from the 1.9.?:j'?.?,''{..... of the stem'

3. The importance of transpiration :

(a) Creates a tfg,?fP.iL:.1:L:]... p.:.11.....,. that sucks water and dissolved mineral salts

from the soil. Mineral salts are used for cell activities while the water is used for

photosynthesis and keeps the cells turgid to give support to the leaves-

(b) Maintains oS.T.9l,iL.... p.f9Li.Yl,9... in the cells due to elimination of excessive water

in.plant bodY.

(c) Gives c9.qli|r.?....... ef.f.9.9.t... due to absorption of latent heat by water to evaporate.

4. Measuring the rate of transpiration.

{a) The pulling force developed by transpiration can be demonstrated in an experiment by

usins p9i9.TS.tS!'..'

(b) This photometer can also be used to measure the rate of photosynthesis under

different envi ronmental condition.

(c) From the diagram shows, the rate of

water loss'is indicated by the speed

of which the air bubble moves along

the graduated capillary tube. (from X

to Y)

Rate of =

water loss

DistanceXtoY(cm)

time

(d) Notice that, the potometer does not

measure transpiration directly and

will give an accurate indication only if

the rate of water loss is PreciselY

equal to the rate of water uPtake.

However, for most purpose the estimated transpiration obtained from the experiment

is satisfactory.

6.4- >c442

rlts

aro

sed

ic,lQ

Iter

ate.

lt by

lent

:rr:irr-s Affecting the Rate of Transpiration

Explanation Graph

'' i, r-.3( vapour that diffuses out of stomata

a .9 3.'l.T .Yl.?.1 9:.. . .. arou nd the leaf surface.

- ','l--ving air carries water vapour away. This

c.[.93.t9.f.... the concentration gradient between

-',aier vapour inside the leaf and outside the leaf.

-lence, the rate of transpiration is increased.

- -re rate of transpiration increases when the

rcvement of air is increased.

c)(otcoCg'-U)c

F

Air movement

" {n increase in temperature, increases the rate

cf transpiration due to:

. lncrease in water e.Y9.P.9.*Jl]9.?.... rate

. lncrease in d.iF.F.Y.9i,9.?.....,... rate

. D.9.9.f.9.::9..... in humidity of surrounding air

a)(!tCo.E(g'o-ac(gF

Temperature ( 'C)

' During the day, high light intensity stimulates

s.igP.g.t9... opening, so the rate of

trans pi rations i .-P 9. l'.9.9.f.9.9. .

:. Heat energy also increases evaporation of

water.

i. At night, stomata close and the rate of

transpiration decrease.

0000 0600 12a0 1800 24aa

>\=ac0),c-.c_9-J

c)(gtc.a(o'dU)

(gF

i. At the l.9.Yl. relative humidity (dry air) the

concentration gradient at water vapour between

the leaves and surrounding is high, so the rate

of transptration is i.?.:.L-e.?.9S3.....'..

2. When the relative humidity is high, the air is

s*3tY.*L1.1... with water vapour. The water is

unable to evaporate from the leaves'Relative humiditv

c)

t.F

'o-<t,C.

F

The Regulation of Transpiration by Stomata

1. Each stoma consists of a pair of kidney shapecl git9.*.. c9.l!.{ surrounding st.qt9'19 p.9f'9"

2. Unlike other celts, guai"d ceils are sP.3.9j3.1*93 epidermal cells with a thicker inner ceilwall

and also contain c.h.lg.tSf '{3i'L:'J. ln dicotyledonous leaves, stomata are found on the lgHgl ... epidermis while

monocotyledonous leaves have stomata on b9i'b.""'. lower and upper epidermis'

4. ln general, stomata oPPl.{..... during the day and c.\9j9-s"...' at night.

rlll

$riiilllll:-,i

l:l ,,,rll:: l

- ,,iil;

!t

Opening Closing

E.Fi9:tT.3.'.... ;.ii* \\v.:.9.q.9J.e....... d(<- -'ii;)

;il;,..ii.; -ffiThin outer cel! wall-fiF1t,U\ i, , i Jl');n,

#;;i::'ffNucleus -r YV;r-

(a)

ctornqtel n oF€v..... t'"'..'"'

t-* * *" tr"*t,r"tis "*r'tguard cells and produce g.t'Y.n9.{9.

K* ions are ap.t!y.9!J...... pumped fromsurrounding epidermal cells into the guard

cells.

An accumulation of K+ ions and glucose

increases the of.T.$.f.1.. p'l9ll'Y.T" ofguard cells.

Water from epidermal cells move into the

g.'J.q.1.9..... cells by osmosis

The guard cells become t.''lt9i'9..'...'. and

curve outward, the stomata open'

Hence, water vapour diffuses out from the

sub stomata air space to the surrounding'

(b)

(c)

(d)

(e)

(f)

a) ln the dark, photosynthesis does not

occur. Sugar and amino acid are

translocated out of the guard cell

(translocation)

K+ ions move out of the guard cells into

the epidermal cells.

Therefore, osmotic pressure of guard cells

d s.: r.q3:.f.f.....

Water diffuses out into the epidermal cells

by osmosis.

The guard cells become fl.?.3.1i.1.".. and

the stomata closed.

Water vapour cannot diffuse out to the

surrounding. Transpiration stops.

(b)

(c)

(d)

(e)

(f)

6.4- >c442

dQuestion 1 paper 3

was carried out by a few Form Four students to investigate the effects of air movement

6l1i i;-anspiration in Hibiscus plant. The set up of the apparatus is shown in Diagram 1.1(a)'

mffapparaius is left on the laboratory table. The stopwatch is started when the fan speed as

ffifnm lmutiat air bubble position are set at 0 as in Diagram 1.1(b). The tirhe taken for the air

ffim,mnove a distance of 10 cm, or PQ is recorded down.

experiment in Diagram 1.1(a) is repeated with the fan speeds set at 1,3 and 5 respectively-

1lll2(p) shows the result obtained from the experiment.

'50 cm

DIAGRAM 1 .1 (a)

Scirle

Initiirl Positionof irir bubble,

DTAGRAM 1.1(b)

Table 1.2(a)

llibiscus plant

-\il bubble

(l:rpillalv tube

^K+ i

!514131211109 8 7 6 5 4 3 21 Ocm fuu T 5'D*so I to

45d1.N l\{inute nkrt 30 Ei

conditions faced by the Hibiscus plant are:

Condition Fan speed Air movement

1 1 Slow

2 ? Moderate

? tr Fast

++ll9i"-sr*1

!f"''

Condition Fan speed Observation Time taken (min

1 1

f.ss so s\*so 10"

4s ,P 15

-4o ,/ 20 -kfr 30 21;l

3+

2 3

{sa 60 s'\'50 1oa

4s\ls-49 \ eo_

\"lu 30 'tga3

3 5

50 10

4s oliu40 20

Fsoz{

le

nt#

tf

tlr*il

Table 1.2(b)

1. (i) From Table 1 .2(b), state two different observations .

1. When the fan speed is ..1.,... the air bubble takes ..?.1.. minutes to move from P to Q

2. When the fan speed is ..f.....tne air bubble takes ...i?.... minutes to move from P to Q

(ii) State the inference which corresponds to the observation in 1 (i).

1. Speed fan 1 is a 1.9.*... speed, the water loss from the Hibiscus plant is s1.93.......

2. Speed fan 5 is a hi9.h... speed, the water loss from the Hibiscus plant is f.9.f1.......

2, Write down the time taken for the air bubble in the potometer to move a distance of PQ for the

differcnt fan speed respectively in table 1.2(b).

+sl!e:f,"*.

l:,-: ele Table 'i.3 based on this expertment

Variable Method to handle the variabie

: -;aied variable

.peed

:,::: : rding variable

--e :.i.T.9..... taken for the air

: - :: 3 to move a o l.i t3?.99. ..,

'::r:- = iO Q

- : -:'ciled variable

*-- tJP9........ of plant

Table 1.3

4 i :r:: :'e hypothesis for this exPeriment. ,

Tth,* * J!9i.tfre fan speed, the sltg.r)fL the time taken for the air bubble to move from P to Q

g l.sed on Table 1.2(b), construct a table and record the results of the experiment which

r: -de the following asPects:

: -he fan speed: r'-ne time taken for the air bubble to move from P to Q

- The rate of transpiration of Hibiscus plant (cm/nin)

toQ

toQ

I for the

Tqe pon sPeed 'lifne fqKen fon*h€ elr bubbt€

*o move f rom P to q cmin)

The Fote oF +naosPilo+ion

of gol sam P lani ( orn /m;o)

o-ei

o.6Jle

r Fi-om the table ln S(i) aOoue, Ora* tne g-rph of the rate of transpiration of Hibiscus plant

against the fan speed.

$ :-:m the table in 5(i) above, explain ihe relationship beiween the fan speed, the time taken for

:-e air bubble to move from P to Q and the rate of transpiration of Hibiscus plant.

*\,ren the fan speed is hi.?1t9.1,.., the time taken for the air bubble to move from P to Q is

r.t:,.".i.ti.1., if..r" rat" of transpiration is h.LQlr.9.f...caused more water loss to the atmosphere

Use d.r$e-q9.Lt.. tan speeds which are

speed1,3and5.

M99S.Y.19.. and record the time taken

for the air bubble to move a distance

from P to Q by using a sIffl.'H:*'i..

F.H......the type of Plant that is

Hibiscus plant.

46llF,,b-S*f