NCERT Solutions for Class 7 Science Chapter 11 Transportation in Animals and Plants
NCERT solutions for class 7 science chapter 11 transportation in animals and plants: Solved Exercise Questions:
Q1. Match structures given in Column I with functions given in Column II.
Column I Column 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
Answer:
The matched structures of column I with functions of column II is given below:
|
Column I |
Column II |
|
(i) Stomata |
(b) Transpiration |
|
(ii) Xylem |
(d) Transport of water |
|
(iii) Root hairs |
(a) Absorption of water |
|
(iv) Phloem |
(c) Transport of food |
Q2. 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 _________ .
Answer:
(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 salt .
(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
Q3. Choose the correct option:
(a) In plants, water is transported through
(i) xylem
(ii) phloem
(iii) stomata
(iv) root hair
Answer:
In plants, water is transported through the xylem .
So, the correct answer is (i) xylem .
Q3. Choose the correct option:
(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
Answer:
Water absorption through roots can be increased by keeping the plants under the fan because the transpiration process is boosted.
THence, the correct answer is (iii) under the fan .
Q4. Why is transport of materials necessary in a plant or in an animal? Explain.
Answer:
Transport of materials is necessary for plants and animals because due to transportation the nutrients and oxygen are made available to all the parts of the body.
If the transport of necessary nutrients and oxygen does not take place in the body, the body will not be able to survive.
Q5. What will happen if there are no platelets in the blood?
Answer:
Blood platelets help to clot the blood. When there is some injury occurs blood starts flowing and if there are no platelets,
the blood will not be able to clot and keep on flowing. Therefore can cause death because of the huge loss of blood.
Q6. What are stomata? Give two functions of stomata.
Answer:
There are small openings or pores on the lower surface of the leaves called stomata these opening are surrounded with guard cells.
The two functions of stomata are:
(i) Transpiration is possible through stomata, i.e., excess water loss from the plant.
(ii) Absorption of water from the roots, when there is loss of water from the stomata creates an upward pull.
(iii) Exchange of gases.
Q7. Does transpiration serve any useful function in the plants? Explain.
Answer:
Transpiration helps in many ways:
(i) To enhance the absorption of water and dissolved minerals by the creation of a suction pull.
(ii) It helps in the loss of excess water from the plant.
(iii) Photosynthesis is possible because of the transportation of water and minerals to the leaves.
Q8. What are the components of blood?
Answer:
There are four components of blood:
(i) Platelets: It helps in the formation of blood clots thus preventing the excessive bleeding from the wounds.
(ii) Plasma : They are present in the blood cells and also contains dissolved nutrients.
(iii) Red blood cells (RBC): They are the most abundant cells in the blood. RBC contains a red pigment called hemoglobin which carries oxygen and transports it to all the parts of the body.
(iv) White blood cells (WBC) : They help the body to fight against the diseases by changing their shapes. Thus, they constitute the immune system of the body.
Q9. Why is blood needed by all the parts of a body?
Answer:
Blood is needed by all parts of the body because it is an important part of the transport system of our body and performs the following these important functions:
(i) Transports oxygen from the lungs to all the body cells.
(ii) Carries carbon-dioxide, waste products back to the lungs so that it can be exhaled easily.
(iii) Blood fights against diseases and infections.
Q10. What makes the blood look red?
Answer:
Blood looks red because of the presence of haemoglobin, a red pigment in the red blood cells or RBC's that makes blood appear red in colour.
The haemoglobin carries oxygen and transports it to all the parts of the body.
Q11. Describe the function of the heart.
Answer:
The human heart is divided into four chambers where the upper two chambers are called right and left atrium and the lower chambers are called the right and left ventricles, therefore the functions of the heart are as follows:
(i) The right atrium receives carbon dioxide-rich blood from the body. Blood from the right atrium enters the right ventricle, which contracts and pumps the blood to the lungs.
(iii) Oxygen-rich blood from the lungs returns to the left atrium, then blood enters the left ventricle which contracts and pumps the blood to all parts of the body.
Hence basic function is to beat with rhythmic contraction and expansion throughout the life and transport the blood as a pump.
Q12. Why is it necessary to excrete waste products?
Answer:
The waste produced by our cells are toxic and therefore need to be excreted out. The process of removal of waste products produced in the cells of living organisms is called excretion.
Q13. Draw a diagram of the human excretory system and label the various parts.
Answer:
The labelled diagram of the human excretory system is shown below: