Selina solutions concise biology class 7 icse Solutions for Chapter 5 excretion in humans

Q1) Define excretion. Write the four organs of human urinary system in their correct sequence.

Q2) Why is excretion necessary in living beings?

Q3) What is meant by osmoregulation?

Q4) Describe the structure of the kidney with the help od a labelled diagram.

Q5) What are the two ways by which a person can get relief in case of kidney failure?

Q6) Draw a diagram of the human excretory system and label the following parts:

Kidney, ureter, urinary bladder and urethra.

Q7) How are kidney stones formed?

Q8) What are the symptoms of a urinary tract infection?

Q1) Put a tick mark against the most appropriate alternative in the following statements:

(a) The kidneys are made up of tubular units called:

1. Glomerulus
2. Nephrons
3. Capillaries
4. Neurons

(b) In human beings, urea is produced in:

5. neuronsLiver
6. Kidney
7. Spleen
8. Urinary bladder

(c) Besides water, the urine mainly contains:

9. Urea
10. Nitric acid
11. Glucose
12. Bile pigments

(d) Filtration of excretory wastes from blood occurs in:

13. Collecting tube
14. Ureter
15. Urinary bladder
16. Nephrons

Q1) Fill in the blanks:

1. Nitrogenous waste in urine is in the form of ____ and _____.
2. The unit of human kidney is called ______.
3. Evaporation of sweat from the skin surface has a _____ effect.

Q2) Define the following :

1. Excretion
2. Excretory organs
3. Dialysis
4. Nephron

Q3) Write true or false for each of the following statements:

1. Removal of solid undigested food is excretion.
2. Medulla of kidney passes urine into urinary bladder.
3. Excess of sugar in blood is a symptom of diabetes.
4. Urine is devoid of blood cells.

Q4) Name the blood vessel that brings blood to the kidneys.

Q5) Where in the urinary system do the following processes take place?