Chapter 1 : transport

Learning objective:1. Understanding the importance of having transport system in

some multicellular organisms2. Synthesise the concept of the circulatory system3. Understanding the mechanism of blood clotting4. Synthesise the concept of the lymphatic system5. Understanding the role of the circulatory system in the

body’d defence mechanism6. Appreciate a healthy cardiovasular system7. Understanding the transport of substances in plants8. Synthesise the concept of the transport of substances in

plants

1.1 The importance of having a transport system in some multicellular organisms

Learning outcomes:1. Identify the problems that could be faced by

multicellular organisms in obtaining their cellular requirements and getting rid of waste product

2. Suggest how these problems are overcome in multicellular organisms

Transport

• To describe how the substance in our body move from one part to the other part

• Transport process varies in different types of organism

Difference transport in unicellular and multicellular organisms

• 1. Unicellular organismEx?

They have large total surface area to volume (TSA/V) ration that enable substance to diffuse easily into the cell

Dimension of cube (cm) 1 x 1 x 1 2 x 2 x 2 4 x 4 x 4

Total surface area of cube (cm2)

Volume of cube (cm3)

TSA/V ratio

small medium large

Calculate the TSA/V ratio.

• To obtain oxygen and nutrients directly from external environment

• Carbon dioxide and other waste product also eliminated by diffusion through plasma membrane

• So, They do not need any internal transport system

Multicellular organismsEx?• The TSA/V ration decreases• Cells often located away from external surface of the

body• Diffusion rate also decrease which is a limiting factor

to cellular activities in large animals• These organism have specialized structure to

increase surface area ( alveolus)• They also need circulatory system to

– Distribute nutrients and oxygen– Remove waste product

1.2 THE CIRCULATORY SYSTEM

1.2 The circulatory systemLearning Outcomes:1. State what a circulatory system is2. State the three components of the circulatory system in humans

and animals3. State the medium of transport in humans and animals4. State the composition of human blood5. Explain the function of blood and haemolymph in transport6. Describe the structure of human blood vessel7. Explain how blood is propelled through human circulatory system8. Explain briefly how blood pressure regulated9. Compare and contrast the circulatory system in the following:

human, fish and amphibians10. Conceptualise the circulatory systems in humans

Functions of the circulatory systemThe circulatory system has three functions:

1. Transporting substances around the body. These include oxygen, glucose, carbon dioxide, nutrients, water and waste products.

3. Protecting the body. Blood contains cells and anti-bodies that fight infection and clotting agents to stop bleeding.

2. Carrying waste product away from the cells.

3 components of circulatory system

1. Medium of transport/ Blood2. Blood vessel3. Heart

HUMAN BLOOD

Composition of Human Blood

• Blood: connective tissue that are composed of1. Cellular components (45%)• Platelets• Erythrocytes (RBC)• Leucocytes( WBC)

2. Plasma (55%)• Water(90%)• Soluble solutes

1. Medium of transport/ BloodAnimals:Blood which consist of blood plasma, blood cells

( RBC, WBC) and plateles

Invertebrates:Ex: Use haemolymph (fluid in hoemocoel) Hoemocoel: rongga

Functions: transport material around the body

BloodBlood is the body’s means of transporting substances around. It transports:

oxygen from the lungs to the heart and then to the body’s tissues

carbon dioxide from the tissues to the heart and then to the lungs to be expired

materials like hormones from one organ to another

nutrients (especially glucose) and minerals from the intestines to the tissues

waste products to the kidneys.

Plasma

90% water - solvent

Ions (Na+, Mg2+, Cl-) – maintain osmotic balance in blood (pH 7.4)

Nutrients (e.g: glucose)

antibodies

urea and other waste products

plasma proteins.(ex: albumin, fibrinogen,prothrombin, globulins)

Dissolved gases( oxygen and carbon dioxide)

Hormones ( insulin)

The blood cells and platelets are suspended in a substance called plasma. Plasma is made up of:

• The plasma is a slightly alkaline fluid, with a typical yellowish color

• The mineral substances are dissolved in ionic form, that is dissociated into positive and negative ions.

• Ex: Ca2+

Plasma can be separated from the other components of blood using a centrifuge.

plasma

Cellular components ( 45%)

1. Platelets

• Fragments of cells from bone marrow

• No nucleus• Important for blood clotting

process

1.Platelets

Formed in red bone marrow.

Produce thrombokinase – a chemical needed for blood clotting.

Platelets help to repair tissues and close wounds both internally and externally.

When needed, they grow into irregular shapes and stick together to form a plug over the wound.

Platelets are also carried in the blood.

2.Red blood cells

Also called erythrocytes.Biconcave Disc-shaped.Made in the bone marrow.Contain a red-coloured compound called haemoglobin which bonds with oxygen to form oxyhaemoglobin.Transport oxygen to the tissues.

Blood is made up of a number of different elements. The most common cell in blood is the red blood cell.

7.5

2.0

Each erythrocytes contains haemoglobin.

Haemoglobin

Oxygen carrying protein pigment – give red color

Contains haem groupHaem group – contains iron atom and is the site of

oxygen binding.• Lifespan is only 120 days • Destroyed in the liver & spleen

3.White blood cells

Also called leucocytes.They are bigger than red blood cells and have large nuclei.Act as the body’s defence system.ColorlessCan be divided into granulocytes & agranulocytes

1. Granulocytes

• Granular cytoplasm• filled with microscopic granules that are little sacs

containing enzymes, compounds that digest microorganisms.

• Lobed nuclei• Form in bone marrowConsist of:1. Basophils2. Neutrophils3. Eosinophils

Neutrophils

• As a Phagocytes• Which digest

bacteria and dead cells

• By phagocytosis process

Neutrophils

Eosinophils

• Control allergic responses

• Kill parasitic worms by release enzyme.

eosinophils

Basophils

• Secretes heparin to prevent blood clotting

• Involve in combating inflammatory and allergic reactions

basophils

• In the different types of granulocytes, the granules are different and help us to distinguish them.

• In fact, these granules have a different affinity towards neutral, acid or basic stains and give the cytoplasm different colors.

• So, granulocytes distinguish themselves in neutrophil, eosinophil and basophil

2. Agranulocytes

• Clear cytoplasm• Nuclei are not lobed

• Consist of1. Lymphocytes2. monocytes

Lymphocytes

• Produce antibodies

• Neutralize toxins• Produce immune

responses against foreign substance

• Largest leucocytes

Monocytes

• Phagocytes • Engulf digested

bacteria and dead cells

• Origin: from bone marrow

Difference between RBC AND WBC

characteristics RBC WBC

1. SHAPE a) Erythrocytes are biconcave disc serves to:

• Increase surface area to volume ratio

• Increase diffusion rate of gaseous exchange

b) No nucleus to gives space for great quantities of haemoglobin

•Leucocytes have nuclei •Not have haemoglobin•Larger than erythrocytes •Do not have fixed shaped

2.FUNCTION •Has haem group•Contains iron atom •For the site of oxygen binding•When the partial pressure of o2 is high, •Haemoglobin will combine with o2 to form•OXYHAEMOGLOBIN

•Responsible for the defense of organism against disease•If pathogen invade the body, number of leucocytes will increase

LIFESPAN 120 daysDestroyed by phagocytes (WBC) in the liver and spleen(limpa)

A few days by phagocytosis process

MANUFACTURED IN

Bone marrowRate: 2 million/ second

Bone marrow(granulocytes)•But may migrate to thymus gland or lymph node •For their growth and development stage•Lymphatic system ( agranucolytes)

3. DIAMETER 8 micrometerThickness: 2 micrometer

15 micro meter

4.Number of blood cell/mm3

5 million/mm3 6000-10000/mm3(Ration: 1WBC:700RBC)

1. Which of the following statements is true about unicellular organisms? Antara penyataan berikut, yang manakah benar tentang ouganisma unisel? A. There are many cells within the organs deep inside the body of unicellular

organisms. Terdapat banyak sel yang membentuk organ yang terdapat di dalam badan organisma unisel.

B. Simple diffusion cannot transport substances fast enough to sustain the life of a unicellular organism. Proses resapan ringkas sahaja tidak memadai untuk mengangkut bahan bagi mengekalkan kehidupan organisma unisel.

C. A simple unicellular organism does not need a special transport system. Organisma unisel yang ringkas tidak memerlukan sistem pengangkutan yang khusus.

D. A simple unicellular organism has most of its cells not in contact with the external environment. Kebanyakan sel bagi organisma unisel tidak bersentuhan dengan persekitaran luar.

1. The following shows several cubes of different sizes. Which of the cubes has the largest TSA/V ratio? Berikut menunjukkan beberapa kiub yang berbeza saiz. Kiub yang manakah mempunyai nisbah JLP/I yang paling besar?

1. Which of the following graphs is true about the TSA/V against the size of the organism?

Antara graf yang berikut, yang manakah benar tentang JLP/I melawan saiz organisma?

A. C.

B. D.

1. What is the liquid component of the blood called? Komponen cecair dalam darah dikenali sebagai apa? A. Platelet C. Plasma Platlet Plasma B. White blood cell D. Nutrient Sel darah putih Nutrien

2. Which of the following is not a function of blood? Yang manakah antara berikut bukan fungsi darah? A. Transport oxygen and nutrients to tissue Mengangkut oksigen dan nutrient ke tisu-tisu B Maintains the body temperature Mengekalkan suhu badan C Protects the body against infections and diseases Melindungi badan daripada jangkitan dan penyakit D Produces enzymes Menghasilkan enzim

Quizzes

1. The neutrophils are _______A. PhagocytesB. LeucocytesC. LymphocytesD. Phosphate

2. Which leucocytes that help to control allergic reaction?A. BasophilsB. EosinophilsC. MonocytesD. Neutrophils

3. Basophils secrete _________ to prevent blood clotting

A. WarfarinB. FibrinogenC. HeparinD. Walfarine

5. Some lymphocytes produce _________ to aid in destruction of __________

A. Antibodies, homogens B. Antibodies, pathogensC. Hormones, pathogensD. Enzymes, pathogens

Functions of blood in Transport

1. Transport in oxygen2. Transport of carbon dioxide3. Transport of water to tissues4. Transport of excretory waste products5. Transport of hormones6. Transport of heat7. Transport of absorbed food materials

1. Transport of oxygen

• Transport o2 from lung/alveolus cells/ all part of body

• Oxygen combine with haemoglobin in erythrocytes to form = oxyhaemoglobin

• Oxyhaemoglobin dissociates into haemoglobin and 02

• O2 then supplied for cellular respiration (ATP) Hb + O2 ---> HbO

<-------

2. Transport of carbon dioxide• Cellular respiration release co2Glucose + o2 - energy +co2+ water• Carbon dioxide transported from cells to lungs/

alveolus in the form of:a)Hydrogen carbonate ionsb) Carbaminohemoglobinc)Dissolves directly in the blood plasma

When the blood reaches the lungs, the co2 release and diffuse out of the blood into the alveoli

• Hydrogen carbonate ions are produced when carbon dioxide produced by tissue respiration is absorbed by blood plasma.

• In your lungs, hydrogen carbonate ions turn back to carbon dioxide which is excreted when you exhale.

• Carbaminohaemoglobin is a combination of carbon dioxide and hemoglobin,

• CO2HHb, being one of the forms in which carbon dioxide exists in the blood.

3. Transport of water to tissues

• Water is transported by blood to provide a medium for biochemical reactions

4.Transport of excretory waste products

1. Deamination• Process removing the amino group from the

excess amino acid. • The amino group is converted to ammonia

and then to urea by the liver• From liver, urea transported by blood to

kidneys to be excreted

5.Transport of hormones

• Blood transport hormones produced by endocrine gland to the target organs

• Ex: insulin and glucagon carried by blood from pancreas to the liver

6. Transport of heat

• Blood helps regulate body temperature by distributing heat

7. Transport of absorbed food materials

• Soluble digested food, vitamins and mineral absorbed into capillaries of the villi in small intestine

• Ex: simple sugar: glucose• Amino acids • Water soluble vitamins• Mineral salts

• They are transported by the hepatic portal vein from small intestine to liver and then to the heart

• Other food materials are absorbed into lacteals in the villi

• Ex: fatty acids, glycerol , vitamin ADEK (Fat soluble susbtances)

• They are then transported by the lymph into the blood circulatory system via the left subclavian vein

Hepatic portal vein

Lacteal and villi

lymph

Subclavian vein

Function of Haemolymph in transport

Haemolymph:• the circulating fluid in open tissue spaces of

invertebrates• A circulating blood-like nutritive fluid which fills

the entire body cavity called haemocoel• A circulating system in invertebrates = open

circulatory system because the haemolymph:

1. Is not confined to vessels only2. Bathes the tissues and internal organs directly

• Nutrients such as digested food and hormones diffuse from haemolymph into cells.

• Waste products diffuse out from cells into the haemolymph

• Haemolymph does not transport respiratory gases.

• Gaseous exchange via the tracheal system

Structure of human blood vessels

2. Blood vessels

• Consist of • arteries• Capillaries• Veins functions: carries blood around the body

Blood vessels

There are three types of blood vessels,

blood from the heart

blood to the heart

arterycarries blood

back intothe heart

carries blood away fromthe heart

carries blood to and from the body’s cells

vein

arteries capillaries Veins•Carry oxygenated blood away from the heart to all parts of the body•Except pulmonary artery

•Sites for the exchange of respiratory gases, nutrients and wastes

•Transport deoxygenated blood from all parts of the body to the heart except pulmonary vein

•Blood pressure:•High blood pressure in arteries

•Lower than arteries but higher than veins

•Lower than arteries

•Thick muscular wall •Lumen size small

•One cell thickness •Lumen is very small

•Thinner wall•Lumen size is large

•No valve except aorta

•No valve •Valve present to prevent backflow of blood

arteries capillaries Veins

To transport blood quickly at high pressure from the heart to tissues

Allow rapid gaseous exchange between blood and the body cells by diffusion

Allow blood from tissues to return to the heart

The ARTERY

thick muscle and elastic fibres

Arteries carry oxygenated blood away from the heart.

the elastic fibres allow the artery to stretch under

pressure

the thick muscle can contract to push the

blood along.

The VEIN

Veins carry deoxygenated blood towards the heart.

thin muscle and elastic fibres

veins have valves which act to stop the blood from going in the wrong direction.

body muscles surround the veins so that when they contract to move the body, they also squeeze the veins and push the blood along the vessel.

The CAPILLARY

Capillaries link Arterioles with Venus

the wall of a capillaryis only one cell thick

they exchange materials between the blood and other body cells.

The exchange of materials between the blood and the body can only occur through capillaries.

Blood vesselsthick outer wall

thick inner layer of muscle and elastic fibres

narrow central tube (lumen)

thin outer wall

thin inner layer of muscle and elastic fibres

wide central tube (lumen)

wall only one cell thick

ARTERY

VEINCAPILLARY

Blood vessels: valves

When blood is flowing against gravity, or when a vein is squeezed by muscle action, there is a risk that blood will flow in the wrong direction. Veins have valves to prevent backflow.

blood to the

heart

backflow prevented vein valve

openvein valve

closed

The valves allow blood to flow in the correct direction…

…but close if blood starts to flow in the

wrong direction.

The figure shows a type of human blood cells. Rajah menunjukkan sejenis sel darah manusia.

Which of the following is true about the cells? Yang manakah antara berikut adalah benar mengenai sel itu? A. They contain haemoglobin. Ia mengandungi hemoglobin. B. They have a lifespan of about 89 days. Ia mempunyai kitar hidup selama 89 hari. C. There are 7000 cells in 1 mm3 blood. Terdapat kira-kira 7000 sel dalam setiap 1 mm3 darah D. They contain nuclei. Mengandungi nukleus.

1.

2.

The figure shows two layers of blood in a test tube. Rajah menunjukkan dua lapisan darah dalam suatu tabung uji.

Which of the following is true about portion Y? Yang manakah antara berikut adalah benar mengenai bahagian Y? A. Y is plasma Y adalah plasma B. Y is the liquid portion of the blood Y adalah bahagian cecair dalam darah C. Y contains nutrients, water, salts and proteins Y mengandungi nutrient, air, garam dan protein D. Y contains red blood cells, white blood cells and platelets Y mengandungi sel darah merah, sel darah putih dan pletlet

3. Which blood cells are matched correctly to their description? Sel darah manakah yang dipadankan dengan betul bersama penerangannya? Blood cells Description A. Platelets Do not contain nuclei and are involved in blood clotting

Tiada nuklei dan terlibat dengan pembekuan darah B. Monocytes Are granulocytes which destroys pathogens through phagocytosis

Merupakan granulosit yang memusnahkan patogen melalui fagositosis C. Neutrophils Made in the bone marrow and produce antibodies to destroy pathogens

Dihasilkan dalam sum-sum tulang dan menghasilkan antibodi untuk memusnahkan patogen

D. Leucocytes Biconcave discs which move easily in the blood capillaries Cakera dwicekung bagi memudahkannya bergerak dalam saluran darah

4.

The diagram shows two types of blood vessels. Rajah menunjukkan dua jenis saluran darah.

Which comparison between the two blood

vessels is correct? Yang manakah merupakan perbandingan antara saluran darah yang betul? X Y A. Located deep within the body

Terletak jauh dalam badan Located nearer to the surface of the skin Terletak berhampiran permukaan kulit

B. Carries oxygenated blood Mengangkut darah beroksigen

Carries deoxygenated blood Mengangkut darah tiada oksigen

C. Carries blood at low pressure Mengangkut darah pada tekanan rendah

Carries blood at high pressure Mengangkut darah pada tekanan tinggi

D. Does not have valves Tiada injap

Has valves Ada injap

What is the function of valves in the vein? Apakah fungsi injap dalam vena? A. Maintain the speed of the blood flow Mengekalkan kelajuan aliran darah B. Stop blood flowing when we are resting Menghentikan aliran darah semasa kita berehat C. Prevent blood from flowing backwards

Menghalang darah daripada mengalir semula ke belakang D. Increase the blood pressure Meningkatkan tekanan darah

5.

The diagram shows cross sections of three types of blood vessels. Rajah menunjukkan keratan rentas bagi tiga jenis saluran darah.

What are X, Y and Z? Apakah X, Y dan Z? X Y Z A. Artery Capillary Vein B. Capillary Vein Artery C. Vein Capillary Artery D. Vein Artery Capillary

6.

3. Heart

• A heart is an organ that generates pressure to pump the blood through out the body

Location of the Heart

• The heart is located between the lungs behind the sternum and above the diaphragm.

• It is surrounded by the pericardium. It is a fluid filled sac that surrounds the heart• Its size is about that of a closed fist, and its

weight is about 250-300 g.

Location of the heart in the thorax

How blood is propelled through the human circulatory system?

Anatomy of the heart

• Heart made up of myogenic cardiac muscles which contract and relax automatically throughout life

• It is not controlled by nervous system

• The human heart has four chambers:1. Left and right Atrium (atria= plural) • Upper chambers which receive blood

returning to the heart• Thin -walled2. Left and right ventricles• Lower chambers which pump blood out

of the heart• Thick walled

Septum:• Separates the right chambers from the left

chambersThe valves: ensure that blood flows only in one

direction.1. Tricuspid valve2. Bicuspid valve3. Semi lunar valve

The Heart Valves • The tricuspid valve- the valve between the

right atrium and right ventricle

• The bicuspid valve- the valve between left atrium and left ventricle

• Semi lunar valve- the valves at the base of aorta and pulmonary artery

• The right pump forces deoxygenated blood to the lungs

• The left pump forces oxygenated blood to other parts of the body

Deoxygenated blood from the body enter the right atrium via

vena cava

oxygenated blood from the lungs enter the left atrium via pulmonary

veins

Pumping of the heart/ the heartbeat

• http://www.pbs.org/wgbh/nova/heart/heartmap.html

How does the heart beat?

The pumping of the heart

Sinoatrial node

Atrio-ventricular node

Bundle of His containing Purkinje tissue

Interventricular septum

SAN and AVN• Electrical signal begins in the sinoatrial (SA) node:

"natural pacemaker." – causes the atria to contract. – Blood is then forced into the ventricles

• The signal then passes through the atrioventricular (AV) node. – sends the signal to the ventricles via the “bundle

of His” – causes the ventricles to contract. – And pump the blood out of the heart

• Right ventricle pumps the blood into pulmonary artery – which forces the blood to the lung

• Left ventricle pumps the blood into aorta – which forces the blood to all part of the body

The Conduction System

• Left ventricle is thicker and more muscular than the wall of the right ventricles

• Because it needs to generate greater pressure to pump blood to all parts of the body

• While the right ventricle pumps the blood to the lungs only

What is the cardiac cycle?

• Cardiac cycle is the series of events that occur during one complete heartbeat

• Including contraction (systole) and relaxation ( diastole) of both atria and ventricles

• The sino atrial node(SAN) can initiate the heartbeat on its own

Sympathetic nerve carrying impulse to the heart can increase the heart rate

Parasympathetic nerve can slow it downThe heart rate increase when:• Increase in the secretion of hormone

(adrenaline)• An increase in partial pressure of carbon dioxide

in the blood• Body temperature is elevated

Contraction of skeletal muscles around veins

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

1.Muscle relaxed , valves closed2.Muscles contract, upper valves open and

blood is forced upwards , lower valve remain close

3. Muscles relaxed, upper valves closed, lower valve opens as a result of muscle contraction elsewhere and blood flows forwards

Regulatory mechanism of blood pressure

• Blood pressure is the force of the blood exerted of the arterial blood vessels

• Arterial blood pressure is highest during ventricular systole , and lowest during diastole

• Baroreceptors monitor the pressure of blood flowing to the body and to the brain

• Baroreceptor located in the walls of the aorta and carotid arteries branch out from the aorta.

Increase in blood pressureBaroreceptor stimulated

Impulse send to cardiovascular control centre(medulla oblongata)

Impulses send via parasympathetic nerve to heart

Contraction of cardiac muscle decrease

Slow down heart beat

Decrease in BP

Normal BP

Decrease in blood pressureIncrease stimulation of the SA node by the sympathetic

nerve

Increase the contraction of the cardiac muscle & smooth muscle of arteries

Increase heart beat

increase in BP

Normal BP

Circulatory systems in insects, fish,

amphibians & human

Circulatory system

Open Circulatory systeme.g: insects

Closed Circulatory system

Double Single e.g: fish

Completee.g: human

Incompletee.g: amphibian

Circulatory system in insects

1. When the heart relax, haemolymph re-enters ostia

2. Valves ensure the haemolymph flow in one direction

Material exchange occurs here. Haemolymph in haemocoel carry nutrients and waste products

Single closed Circulatory system in fish

• Heart consists of 2 separate chambers: an atrium & ventricle.

• Deoxygenated blood leaves the heart at high pressure and passes through the gills where the gaseous exchange occurs.

• Oxygenated blood flows through the organs and blood pressure drops.

Sinuses

Incomplete double closed Circulatory system in amphibians (eg:frogs)

• Double circulatory system:– Pulmonary circulation– Systemic circulation

• Have three-chambered heart (2 atria & 1 ventricle)

• Mixing of oxygenated and deoxygenated blood in ventricle. The mixed blood enters the systemic circulation.

Circulatory system in humans• Double circulatory system (blood passes through the heart

twice for each circuit)– Pulmonary circulation– Systemic circulation

• Two divisions of heart: – Right side pump deoxygenated blood to the lungs– Left side pump oxygenated blood to the body (except lungs)

• Advantage: blood returns to the heart to be pumped again will increase the blood pressure and flow rate, thereby speeding up delivery O2 to the tissues and organs.

Dolphin circulatory system?

The mechanism of blood clotting

The necessities of blood clotting

• To prevent:– serious blood loss– the entry of microorganisms and foreign

particles into the blood

• To maintain:– normal blood pressure– circulation of blood in a closed

circulatory system

The mechanism of blood clotting

• When you get cut, ___________exposed to air become sticky and clump together to plug the wound.

• Platelets release ____________(clotting factor) in the presence of ___________ ions

• Its converts prothrombin into __________• The formation of prothrombin in the liver

requires___________

platelets

thrombokinaseCalcium ion

thrombin

Vitamin K

• Trombin converts soluble plasma protein, ____________ into insoluble _____________ which form a meshwork of threads over the wound

• As blood flow out, erythrocytes and platelets are trapped in the fibrin fibres and a blood clot form.

• The blood clot dries to form a scab which cover the wound.

fibrinogen Fibrin fibres

CONSEQUENCES OF IMPAIRED BLOOD CLOTTING MECHANISM

Haemophilia

• Haemophilia is a hereditary disease due to the lack of certain gene for the production of certain clotting factor

• It causes serious bleeding particularly in the joints.

Thrombosis

• Blood clot is sometimes formed on the damaged rough inner wall of artery. This clot is called thrombus.

• Thrombus may cause blockage of the artery and this is known as thrombosis.

• When the thrombus dislodges and carried away by blood circulation, it is known as embolus.

• Embolus may trapped in the small artery and block the flow of blood. The condition is called embolism.

Impaired blood clotting mechanisms in human

The consequences

HEART ATTACK

angina

DEEP VEIN THROMBOSIS

STROKE

SPEED QUIZ

1. The list below shows four types of plasma proteins involved in the blood clotting mechanism. Senarai di bawah menunjukkan empat jenis protein plasma yang terlibat dalam mekanisme pembekuan darah.

Fibrinogen

Thrombokinase

Thrombin

Prothrombin

Which of the following is the correct sequence in the blood clotting mechanism? Antara yang berikut, yang manakah merupakan susunan yang betul dalam mekanisme pembekuan darah?

A. Prothrombin →Thrombokinase →Thrombin →Fibrinogen Protrombin →Trombokinase →Trombin →Fibrinogen

B. Fibrinogen → Prothrombin → Thrombokinase → Thrombin Fibrinogen → Protrombin → Trombokinase → Trombin

C. Thrombokinase → Prothrombin → Thrombin → Fibrinogen Trombokinase → Protrombin → Trombin → Fibrinogen

D. Thrombin → Prothrombin → Thrombokinase → Fibrinogen Trombin → Protrombin → Trombokinase → Fibrinogen

1. What is the clotting factor released by the platelets? Apakah faktor pembeku yang dibebaskan oleh platlet? A. Thrombokinase

Trombokinase B. Prothrombin

Protrombin C. Thrombin

Trombin D. Fibrinogen

Fibrinogen

BIOLOGY FORM 5

FORMATION OF INTERSTITIAL FLUID

• Blood flows from arteries capillaries, there is a higher hydrostatic pressure at the arterial end of the capillaries.

• Higher pressure forces some fluid out through capillary wall into intercellular spaces between cells.

• fluid interstitial fluid @ tissue fluid

• The interstitial fluid that has not been reenter into bloodstream goes into lymph capillaries.

• Fluid is known as lymph

COMPOSITION OF INTERSTITIAL FLUID

• Similar to the blood plasma.

• Contains water + dissolved oxygen + amino acids + glucose + fatty acids + glycerol + vitamins + minerals + hormones.

• Has no erythrocytes, platelets or large protein molecules.

The Importance of Interstitial Fluid

• It is important because:–Form the internal environment of the body–Bathes the cells & supplies them with cellular

requirement. E.g: oxygen and nutrients.–Excretory waste product diffuse out of the

cells into the interstitial fluid.

THE FATE OF INTERSTITIAL FLUID• 90% interstitial fluid flow back into the venous end of the

capillary system where the hydrostatic pressure is low.

• 10% of interstitial fluid drains into the lymphatic capillaries forming lymph.

• If excess interstitial fluid unable to return cause tissue swelling oedema

The structure of the lymphatic system

• The three parts of the lymphatic system are: –The lymph vessels–The lymph nodes–The lymph capillaries

lymphatic capillaries• Blind-ended tubes or

closed at one end.• Located in the spaces

btween the cells.• The non absorbed

interstitial fluid is drain into these capillaries

• Fluid lymph• It is unite to form

lymphatic vessels.

lymphatic vessels

• Lymph capillaries unite to form larger lymphatic vessels.

• Have one- way valves• Prevent back

flow of lymph• Ensure the

continuous flow of the lymph away from the tissue.

Lymph nodes• Located at interval

along the lymphatic vessel.

• Produce and store lymphocytes that help to defend body agaisnt infections.

The flow of lymph

Received lymph from:1. Right arm2. Shoulder area3. Right side of neck

and head

Received lymph from:1. Left of neck, head

and chest2. Left upper limb3. Entire body below

the rib

Essay- spm 2008

(b) (i) S: fish T: human being

(ii) Similarities• Both have a closed circulation• Blood flows in blood vessels

DifferencesS / Fish T / Human

Single circulation Double circulationHeart has two chambers

Heart has four chambers

Absence of septum Presence of septumOxygenated blood flows from the gills to body

Oxygenated blood flows from the lung to the heart