Ncert solutions for class 7 science Transportation in Animals and Plants

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class 7 science transportation in animals and plants
class 7 science transportation in animals and plants

Ncert solutions for class 7 science Transportation in Animals and Plants – Chapter 11 – with questions and answers pdf as well as mcq with answers

Summary of Ncert solutions for class 7 science Transportation in Animals and Plants

This chapter is on the Circulatory system and its components in plants and animals. This system transports materials like nutrients, fiber, oxygen and carbon dioxide. through blood. It also talks about the execratory system.

Ncert solutions for class 7 science Transportation in Animals and Plants

Circulatory system – Ncert solutions for class 7 science Transportation in Animals and Plants

Blood

  • Blood is a fluid tissue that transports nutrients and oxygen to the cells and carries away carbon dioxide and other waste products in our body.
  • The fluid part of blood is called plasma and has various salts and nutrients dissolved in it. Plasma is mostly made up of water (up to 95%) and contains dissolved nutrients, carbon dioxide and oxygen.
  • Blood consists of Red blood cells (RBCs) which carry oxygen to various parts of our body, White Blood Cells (WBCs) which are a part of our immunity system and Platelets which provide for clotting of blood.

Blood vessels

  • They carry the blood to different parts of our body.
  • There are three types – arteries (carry oxygenated blood to the cells and tissues of our body), veins (carry away deoxygenated blood from the cells and tissues of our┬ábody) and capillaries (exchange of material between circulation and cells).

Read more: NCERT Solutions For Class 7 Science Chapter 7 Weather, Climate and Adaptations of Animals to Climate

Heart

  • It pumps blood through blood vessels to all the parts of the body.
  • The upper chambers are called atria and the lower chambers are called as ventricles.

Valves

  • They are present between atria and ventricles and at the base of big vessels leaving the heart and ensures unidirectional flow of blood.

Pulmonary circuit

  • It is the network of arteries and veins connecting the heart and lungs.

Alveoli

  • They have blood vessels wrapped around it and the blood is oxygenated by diffusion.

Pulse

  • The heart periodically expands and contracts to pump blood into the arteries, which also expands and contracts as the blood flows through them. This is called pulsation.
  • Pulsation is measured as the number of heartbeats per minute, which is nothing but pulse rate.

Execratory System

The process of removal of waste products from the cells of living organisms is called excretion.

Kidneys, Ureters and Urinary Bladder

  • We have two kidneys that produce urine for excretion and it contains millions of tiny tubules that act as microscopic filters and filter out the useful and harmful substances from the blood.
  • The useful substances are again reabsorbed back into the blood and only harmful substances are concentrated.are present in a dissolved state in water and now it is called as urine.
  • Urine is sent from the kidneys to the urinary bladder through tubes called ureters.
  • The urinary bladder is a muscular bag where urine is accumulated and excreted from the body through the urethra.

Transportation in Plants

Xylem and Phloem

  • Phloem is the plant tissue that transports the soluble and organic material created during photosynthesis from the leaves to the other parts of the plant
  • Xylem is the plant tissue that transports the water and other nutrients from the roots to other parts of the plant.

Transpiration

  • Transpiration is the loss of water in the form of water vapour from stomata present on leaves.

Conclusion

Ncert solutions for class 7 science Transportation in Animals
and Plants – Chapter 11 – with questions and answers pdf as well as mcq with answers has been provided with a summary and explanation as seen above.

Questions and Answers – Ncert solutions for class 7 science Transportation in Animals and Plants

1. Match structures given in Column I with functions given in Column II.

Column- IColumn-II
(i) Stomata(a) Absorption of water
(ii) Xylem(b) Transpiration
(iii) Root hairs(c) Transport of food
(iv) Phloem(d) Transport of water
(e) Synthesis of carbohydrates

Solution:

Column- IColumn-II
(i) Stomata(b) Transpiration
(ii) Xylem(d) Transport of water
(iii) Root hairs(a) Absorption of water
(iv) Phloem(c) Transport of food

2. Fill in the blanks.

(i) The blood from the heart is transported to all parts of the body by the .

(ii) Haemoglobin is present in cells.

(iii) Arteries and veins are joined by a network of .

(iv) The rhythmic expansion and contraction of the heart is called .

(v) The main excretory product in human beings is .

(vi) Sweat contains water and .

(vii) Kidneys eliminate the waste materials in the liquid form called .

(viii) Water reaches great heights in the trees because of suction pull caused by .

Solution:

(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 .

Short answers – Ncert solutions for class 7 science Transportation in Animals and Plants

3. Choose the correct option:

(a) In plants, water is transported through

(i) xylem

(ii) phloem

(iii) stomata

(iv) root hair

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

(i) in the shade

(ii) in dim light

(iii) under the fan

(iv) covered with a polythene bag

Solution:

a) i) Xylem

b) iii) under the fan

Short answers – Ncert solutions for class 7 science Transportation in Animals and Plants

4. Why is transport of materials necessary in a plant or in an animal? Explain.

Solution:

Transport of materials is necessary in a plant or an animal for the following reasons:

  • To transport food to various parts of the body
  • Animals need to transport wastes to parts from where they can be removed.

5. What will happen if there are no platelets in the blood?

Solution:

If there are no platelets, then blood will not clot as platelets release blood clotting factor at the site of injury.

6. What are stomata? Give two functions of stomata.

Solution:

Tiny pores present on the leaf surface are known as stomata.

Functions of stomata

  • Helps in exchange of gases
  • Evaporation of water through leaves occurs due to stomata.

7. Does transpiration serve any useful function in the plants? Explain.

Solution:

Transpiration serves the following functions in plants

  • It helps in lowering temperature of plants, thus preventing heat injury of plants.
  • Helps in transpiration pull, which helps in raining water in higher plants.
  • It also causes loss of water absorbed by plants.

8. What are the components of blood?

Solution:

Red blood cells, white blood cells, platelets and plasma.

Short answers – Ncert solutions for class 7 science Transportation in Animals and Plants

9. Why is blood needed by all the parts of a body?

Solution:

Blood is a significant part of transport system in our body, and we need blood for the following reasons:

  • For the transport of oxygen to all parts of our body
  • To expel out carbon dioxide from our body
  • To transmit heat thus helping in the regulation of body temperature.
  • It is required to fight out infections and diseases.

10. What makes the blood look red?

Solution:

Haemoglobin, a red pigment present in the blood makes it look red.

11. Describe the function of the heart.

Solution:

The heart is an organ which beats continuously to act as a pump for the transport of blood, which carries other substances with it. The heart has four chambers. The two upper chambers are called the atria (singular: atrium), and the two lower chambers are called the ventricles. The partition between the chambers helps to avoid mixing up of blood-rich in oxygen with the blood-rich in carbon dioxide. Blood flows from the heart to the lungs and back to the heart from where it is pumped to the rest of the body.

12. Why is it necessary to excrete waste products?

Solution:

When our cells perform their functions, certain waste products are released. These are toxic and hence need to be removed from the body.

13. Draw a diagram of the human excretory system and label the various parts.

Solution:

human excretory system