[Form3/SC]Chapter 3: Excreation

science chap 3 : excretion

Name : Siti Nur Syukria Bt Sufakhi Class : 3 Rafflesia Teacher : Pn. Normariha

Human excretion

eliminate Carbon dioaxide and water through L ungs * Cortex *Medulla *Pelvis

Water, Urea and mineral salts through

Kidne y Urinary bladder

S kin *Sweat gland *Sweat pores

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 and KIDNEYS. • If excretory products like urea, carbon dioxide, excess mineral salts and excess water are allowed to accumulate in the body, it will become poisonuis (toxic) and endanger health.

EXCRETORY ORGANS Excretory Method

Excretory Products

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. Water + Mineral Salts + Urea  Sweat

EXCRETORY ORGANS Excretory Method

Excretory Products

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. Water and Carbon dioxide

EXCRETORY ORGANS Excretory 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.

URINARY SYSTEM

1) The urinarry system is part o excretory system. 2)The uninary system cosists o a)a pair of kidneys b)a urinary bladder c)a pair of ureters d)urethra 3) The blood carried by the renal artery to the kidney is filtered and excretory product are the eliminated from the blood as urine.

HUMAN KIDNEYS 1) The kidneys are situated to the left and right back section of the abdominal cavity. 2)Human kidneys are dark red in colour 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.

HUMAN KIDNEYS

ORGAN S FUNCTION Channels urine from the kidneys to the Ureter urinary bladder Urinary Bladde r Stores urine Urethr a

Channels urine from the urinary bladder out of the body

Renal Artery

Transports oxygenated blood to the kidneys

Renal Vein

Transports deoxygenated blood away from the kidneys

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 nitrogenous substances like urea and uric

The importance of maintaining a healthy kidney • Under normal conditions, substances like protein(amino acids) and glucose are not found in 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 this will lead to death. • The kidney will function properly if we :

PLANT EXCREATION

eliminate

Carbon dioxide, oxygen and water through

Leaf Stom ata

Water, urea and mineral through salts

Quinine and tannin

Tree Stem

B ark

through

excretion in plants • Plants do not have a specific excretory system. • Respiration in plants eliminates carbon dioxide and water. • Photosynthesis eliminates excess water nfrom plants. • Complex excretory products gather on LEAVES, FLOWERS, BARK, STEMS, FRUIT etc. to be dropped or eliminated. • Some excretory products of plants are beneficial while some are dangerouse to humans. • Some beneficial excretory products of the plants can endanger human heatlh if misused.

Beneficial Excretory Products Of Plants And Their Uses EXCRETORY 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 (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

Oil

Flowers or leaves of certain trees

To make perfume and ointment for insect bites

Excretory Products Of Plants That Dangerous To Humans EXCRETORY 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

Bark of plants like Acid (tannic the tea, coffee and acids or tannin) mangrove 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