nota excretion

7/29/2019 nota excretion

1/15

science

chap 3 :

excretion


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Human excretion

* Cortex

*Medulla

*Pelvis

Urinary

bladder

*Sweat gland

*Sweat pores

eliminate

throughthrough


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Excretory System Excreation is a process of removing substances that are of

no use or in excess from body.

Human excretory organs are SKIN, LUNGS andKIDNEYS.

If excretory products like urea, carbon dioxide, excessmineral salts and excess water are allowed to accumulatein the body, it will become poisonuis (toxic) and endangerhealth.


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EXCRETORY ORGANSExcretory Method SWEATING

1)The sweat glands absorbs

excretory product from blood

capillaries around it.

2)Sweat is eliminated from the

sweat gland through sweat

pores to the surface of the skin.

Excretory Products Water + Mineral Salts + Urea

Sweat


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Excretory Method RESPIRATION

1)Carbon dioxide in the

blood capillaries diffuses

into the alveolus and is

eliminated from the lungs

when exhaling.

2)Water is eliminated from

the lungs in the form of

water vapour.

Excretory Products Water and Carbon dioxide

EXCRETORY ORGANS


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EXCRETORY ORGANSExcretory Method URINATION.

1)Excretory products are carried

by the blood to the kidney and

then eliminated as urine.

**Kidney eliminated many

substances in large quantities.

Excretory Products Water, Urea and excess Mineral

Salts.


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URINARY SYSTEM1) The urinarry system is part ofexcretory system.

2)The uninary system cosists of :

a)a pair of kidneys

b)a urinary bladderc)a pair of ureters

d)urethra

3) The blood carried by the

renal artery to the kidney isfiltered and excretory products

are the eliminated from the

blood as urine.


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HUMAN KIDNEYS1) The kidneys are situated to the left

and right back section of the

abdominal cavity.

2)Human kidneys are dark red incolour and is bean-shaped.

3)The outer part which is dark red in

colour named cortex

4)The inner part which is light red in

colour named medulla

5)The pelvis is the part where the

ureter begin.


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HUMAN KIDNEYS

ORGANS FUNCTION

Ureter

Channels urine from the kidneys to the urinary

bladder

Urinary

Bladder Stores urine

Urethra

Channels urine from the urinary bladder out of the

bodyRenal

Artery Transports oxygenated blood to the kidneys

Renal

Vein

Transports deoxygenated blood away from the

kidneys


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HUMAN KIDNEYS Functions of kidneys :

a)eliminating excess water and the mineral

salts in the body

b)regulating the amount of water and

mineral salts in the body.

c)regulating the blood concentration.

d)helping to removes nitrogenoussubstances like urea and uric acid from the

body


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The importance of maintaining a healthy

kidney Under normal conditions, substances like

protein(amino acids) and glucose are not foundin the urine.If glucose is found in the urine, it is

most likely the person has diabetes. If kidneys do not function properly, toxic

substances in the blood will accumulate and thiswill lead to death.

The kidney will function properly if we :a)drink a lot of clean water.

b)avoid drinking alcohol.

c)reduce drinking gassy drinks.

d)reduce eating food with high sugar content


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PLANT

EXCREATION

Leaf

Stomat

a

Tree

Stem

Bar

k

eliminate

throughthrough through


13/15

excretion in plants Plants do not have a specific excretory system.

Respiration in plants eliminates carbon dioxide andwater.

Photosynthesis eliminates excess water nfrom plants.

Complex excretory products gather on LEAVES,FLOWERS, BARK, STEMS, FRUIT etc. to bedropped or eliminated.

Some excretory products of plants are beneficial whilesome are dangerouse to humans.

Some beneficial excretory products of the plants canendanger human heatlh ifmisused.


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Products Of Plants And Their

UsesEXCRETORYPRODUCT SOURCE USE

Latex Rubber tree To make vehicle tyres

ResinCertain tree stems like thecasuarina tree To make varnish and gum

Gum

Certain tree stems like the

acacia tree To make cough madicine

Acid (tannic

acids or tannin)

Bark of plants like the tea,

coffee and mangrove tree To make ink

Quinine Bark of cinchona tree To make to treat malaria

OilFlowers or leaves ofcertain trees

To make perfume and ointment for insectbites


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Excretory Products Of Plants That

Dangerous To HumansEXCRETORY

PRODUCT SOURCE USE

Latex Rubber tree To make vehicle tyres

Resin

Certain tree stems like

the casuarina tree To make varnish and gum

Gum

Certain tree stems like

the acacia tree To make cough madicine

Acid (tannicacids or tannin)

Bark of plants like the

tea, coffee andmangrove tree To make ink

Quinine Bark of cinchona tree To make to treat malaria

Oil

Flowers or leaves of

certain trees

To make perfume and ointment fot

insect bites

nota excretion

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