Question 1

Question 1(iii)Gigantism and Acromegaly are due to:Hypersecretion of Growth hormoneHypersecretion of ThyroxineHyposecretion of Growth hormoneHyposecretion of Thyroxine

Accepted Answer

Hypersecretion of Growth hormoneReason — Acromegaly and Gigantism are disorder in adults in which the pituitary gland produces too much of Growth hormone.

Question 2

Question 1(vi)The blood vessel that carries oxygenated blood is :Pulmonary arteryPulmonary veinRenal veinHepatic vein

Accepted Answer

Pulmonary veinReason — The pulmonary veins carry oxygenated blood from the lungs to the left atrium.

Question 3

Question 1(vii)Organ of corti is present inside the :CochleaSemicircular canalsSacculusUtriculus

Accepted Answer

CochleaReason — The Organ of corti is present in the cochlea. It is a structure present on the basilar membrane. It contains hair cells that act as auditory receptors.

Question 4

Question 1(viii)The structure that stores urine temporarily is :UreterUrethraUrinary bladderKidneys

Accepted Answer

Urinary bladderReason — The urine formed in kidneys is taken by ureters to urinary bladder where it is temporarily stored.

Question 5

Question 1(x)The main nitrogenous waste formed in the human body :Uric acidUreaAmmoniaCreatinine

Accepted Answer

UreaReason — Urea forms the main nitrogenous waste in human body.

Question 6

Question 2(i)Simple goitre is usually seen in people living in the hilly regions. Give two reasons for the statement.

Accepted Answer

Simple goitre is usually seen in people living in the hilly regions because:Iodine is deficient in soil of hilly regions and hence in the food grown there.Iodine is also deficient in drinking water available in the hilly regions which is obtained from rivers and streams fed by melting snow.

Question 7

Question 2(ii)What are the two types of blood circulation in humans?

Accepted Answer

The two types of blood circulation in humans are:Pulmonary circulationSystemic circulation

Question 8

Question 2(iv)Draw a neat diagram of a Neuron and label any two parts.

Accepted Answer

Diagram of Neuron with Cyton and Axon labelled is shown below:

Question 9

Question 3(i)What is Adrenal Virilism? What causes this condition?

Accepted Answer

The overgrowth of adrenal cortex in a mature woman leads to the development of certain male characteristics in her such as a beard, a moustache and deep male voice. This condition is known as Adrenal Virilism.It caused due to the oversecretion of sex corticoids (adrenal androgens).

Question 10

Question 4(i)Name the endocrine gland that secretes Thyroxine. Give any one function of Thyroxine.

Accepted Answer

Thyroid gland secretes thyroxine.One function of thyroxine — It regulates the basal metabolism, i.e., the rate of cellular oxidation resulting in heat production at rest.

Question 11

Question 4(iii)Define the term Synapse. How are Cytons and Axons of neurons placed in the Cerebrum?

Accepted Answer

Synapse is the point of contact between the terminal branches of the axon of a neuron with the dendrites of another neuron separated by a fine gap.In the Cerebrum, Cytons are present in the outer portion (cortex) constituting the gray matter and Axons are present in the inner portion constituting the white matter.

Question 12

Question 4(iv)Name the three membranous coverings of the human brain.

Accepted Answer

Dura mater (outer layer)Arachnoid (middle layer)Pia mater (inner layer).

Question 13

Question 5(i)Name the nerve that transmits impulses to the brain from :(a) Ear(b) Eye

Accepted Answer

(a) Auditory nerve(b) Optic nerve

Question 14

Question 5(ii)A mature mammalian erythrocyte lacks nucleus and mitochondria but is efficient in its functioning. Explain by giving suitable reasons.

Accepted Answer

Lack of nucleus and mitochondria helps erythrocytes in the following ways:Loss of nucleus makes the red cells biconcave, thus increasing their surface area to absorb more oxygen.Loss of mitochondria means that they cannot use the absorbed oxygen themselves.

Question 15

Question 5(iii)The diagram given below is that of a human brain. Answer the questions that follow :(a) Label the parts numbered 2 and 3.(b) State any one function of the part numbered 1.

Accepted Answer

(a) Parts numbered 2 and 3 are:2 → Cerebellum3 → Medulla oblongata(b) The part labelled as 1 is Cerebrum. It is the seat of intelligence, consciousness and will-power. It controls all voluntary actions.

Question 16

Question 5(iv)What is a reflex action? Name the two types of reflexes.

Accepted Answer

Reflex action is an automatic/quick/immediate, involuntary action in the body brought about by a stimulus. The two types of reflexes are natural reflexes and conditioned reflexes.

Question 17

Question 6(i)Give the exact location of Pulmonary semilunar valve. When does it close?

Accepted Answer

Pulmonary semilunar valves are located at the opening of the right ventricle into the pulmonary artery. It closes during the atrial systole phase of the cardiac cycle.

Question 18

Question 6(ii)Name the hormones whose deficiency causes :(a) Diabetes mellitus(b) Diabetes insipidus

Accepted Answer

(a) Diabetes mellitus - Insulin(b) Diabetes insipidus - Vasopressin

Question 19

Question 6(iii)Draw a neat diagram of a longitudinal section of a human kidney and label Renal Cortex and Renal Medulla on the diagram.

Accepted Answer

Diagram showing longitudinal section of a human kidney with Renal Cortex and Renal Medulla labelled is shown below:

Question 20

Question 6(iv)Mention one function for each of the following:(a) Lymphocytes(b) Thrombocytes(c) Neutrophils

Accepted Answer

(a) Lymphocytes produce antibodies which kill or neutralise the germs or the poisons from them.(b) Thrombocytes help to form blood clots in order to slow or stop bleeding and help wounds to heal.(c) Neutrophils engulf bacterial and fungal pathogens through a process known as phagocytosis.

Solved 2022 Semester 2 Question Paper ICSE Class 10 Biology

Section A 10 Marks

Section B 30 Marks