NCERT Class VII Science Solutions: Chapter 11-Transportation in Animals and Plants Part 2

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VERY SHORT ANSWER QUESTIONS

Question 7:

Veins have valves which allow blood to flow only in one direction. Arteries do not have valves. Yet the blood flows in one direction only. Can you explain why?

Answer:

Blood flow in arteries is rapid and at a high pressure. Also arteries have thick elastic walls.

Image of direction of blood flow

Direction of Blood Flow

Image of direction of blood flow

Question 8:

What is the special feature present in a human heart which does not allow mixing of blood when oxygen-rich and carbon dioxide-rich blood reach the heart?

Answer:

Heart is partitioned into four chambers.

Image of four chambers of heart

Four Chambers of Heart

Image of four chambers of heart

Question 9:

Name the organ which is located in the chest cavity with its lower tip slightly tilted towards the left.

Answer:

Heart.

SHORT ANSWER QUESTIONS

Question 10:

Look at Figure. Draw another figure of the same set-up as would be observed after a few hours.

Result for Potato in sugar leval check (Q)

Potato in Sugar Leval Check (Q)

Result for Potato in sugar leval check (Q)

Answer:

Result for Potato in sugar leval check (A)

Potato in Sugar Leval Check (A)

Result for Potato in sugar leval check (A)

Question 11:

Arrange the following statements in the correct order in which they occur during the formation and removal of urine in human beings.

  1. Ureters carry urine to the urinary bladder.

  2. Wastes dissolved in water are filtered out as urine in the kidneys.

  3. Urine stored in urinary bladder is passed out through the urinary opening at the end of the urethra.

  4. Blood containing useful and harmful substances reaches the kidneys for filtration.

  5. Useful substances are absorbed back into the blood.

Answer: