Transportation in Animals and Plants

• (i) The blood from the heart is transported to all parts of the body by the arteries.
• (ii) Haemoglobin is present in red blood cells.
• (iii) Arteries and veins are joined by a network of capillaries.
• (iv) The rhythmic expansion and contraction of the heart is called heartbeat.
• (v) The main excretory product in human beings is urea.
• (vi) Sweat contains water and salts.
• (vii) Kidneys eliminate the waste materials in the liquid form called urine.
• (viii) Water reaches great heights in the trees because of suction pull caused by transpiration.

(a) In plants, water is transported through:

(i) xylem

(b) Water absorption through roots can be increased by keeping the plants:

(iii) under the fan (because transpiration increases)

Transport is necessary because every cell needs specific substances (like oxygen, water, food) to perform its functions and release energy. Also, waste products (like CO2, urea) produced in cells are toxic and need to be transported to excretory organs for removal. Without transport, cells would die.

Platelets are responsible for clotting of blood. If there are no platelets, blood will not clot in case of an injury. This will lead to excessive loss of blood which can be fatal.

Stomata are tiny pores present on the surface of leaves.

Functions:

1. Exchange of gases (O2 and CO2) during respiration and photosynthesis.
2. Loss of excess water in the form of vapour (Transpiration).

Yes, Transpiration is very useful:

1. It creates a suction pull which helps in pulling water and minerals from roots to tall trees.
2. It helps in cooling the plant (like sweating does for humans).

Components of blood are:

1. Plasma: The fluid part.
2. RBC (Red Blood Cells): Contain haemoglobin, carry oxygen.
3. WBC (White Blood Cells): Fight against germs.
4. Platelets: Help in clotting of blood.

Blood is needed to:

1. Transport digested food from small intestine to other parts.
2. Transport oxygen from lungs to body cells.
3. Transport waste products for removal.

The presence of a red pigment called Haemoglobin in the Red Blood Cells (RBCs) makes the blood look red.

The heart acts as a pump to circulate blood throughout the body. It beats continuously. It receives carbon dioxide-rich blood from the body and sends it to lungs for purification. It receives oxygen-rich blood from lungs and pumps it to the rest of the body.

When our cells perform functions, certain waste products are released (like urea, CO2). These are toxic and can damage our body if accumulated. Hence, it is necessary to remove them.

(Ref: Textbook Diagram)

• Kidneys (Bean shaped)
• Ureters (Tubes)
• Urinary Bladder
• Urethra
• Urinary Opening

• Blood: Transport medium. Plasma (Fluid) + RBC (Oxygen) + WBC (Defence) + Platelets (Clotting).
• Arteries: Carry Oxygen-rich blood AWAY from heart. Thick elastic walls. High pressure. No valves.
• Veins: Carry CO2-rich blood TOWARDS heart. Thin walls. Low pressure. Have Valves.
• Capillaries: Extremely thin tubes joining arteries and veins. Exchange of materials happens here.
• Heart: Muscular pump. 4 Chambers (2 Auricles, 2 Ventricles). Partition avoids mixing of blood.

• Excretion: Removal of waste produced in cells.
• Human System: Kidneys (Filter blood) -> Ureters (Transport urine) -> Bladder (Store) -> Urethra (Exit).
• Dialysis: Artificial kidney machine used when kidney fails.
• Forms of Waste:
  • Fish: Ammonia (Gaseous form, dissolves in water).
  • Birds/Lizards/Snakes: Uric Acid (Semi-solid white).
  • Humans: Urea.

• Xylem: Pipe-like vessels. Transport **Water and Minerals** from roots to leaves (Upward). Continuous channel.
• Phloem: Transports **Food** (Glucose) from leaves to all parts of plant. Bi-directional.
• Transpiration: Loss of water vapour through stomata. Generates suction pull (Transpiration Pull) to lift water.

• Pulse Rate: Number of heartbeats per minute. Normal = 72-80 beats/min.
• Stethoscope: Device used by doctors to amplify sound of heart.
• Sponges and Hydra: Do not have blood system. Water carries food and oxygen and takes away waste being circulated.
• Root Hairs: Increase surface area for absorption of water.

• William Harvey discovered Blood Circulation. He was ridiculed as 'Circulator'.
• An adult human has 4-5 litres of blood.
• Urine consists of 95% water, 2.5% urea and 2.5% other wastes.
• Pulmonary Artery: Carries CO2 rich blood (exception to artery rule).
• Pulmonary Vein: Carries Oxygen rich blood (exception to vein rule).