Which part of the nephron is impermeable to water

• Proximal convoluted tubule

• Distal convoluted tubule

• Ascending limb of loop of Henle

• Descending limb of loop of Henle

Pick the correct group consisting of all genera exhibiting homospory

• Lycopodium, Psilotum, Selaginella, Equisetum

• Equisetum, Pteris, Salvinia, Psilotum

• Salvinia, Pteris, Lycopodium, Selaginella

• Equisetum, Psilotum, Lycopodium, Pteris

An artificial pacemaker is implanted subcutaneously and connected to the heart in patients

• having 90% blockage of the three main coronary arteries

• having a very high blood pressure

• with irregularity in the heart rhythm

• suffering from arteriosclerosis

Achondroplasia is a disease related with the defect in the formation of

• membrane

• cartilage

• mucosa

• none of these

Assertion: Photorespiration is a wasteful process where there is no synthesis of ATP energy.

Reason: RuBisCO is present in mesophyll cells of C₄ plants hence they show more productivity.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Unidirectional transmission of a nerve impulse through nerve fibre is due to the fact that

• nerve fibre is insulated by a medullary sheath

• sodium pump starts operating only at the cyton and then continues into the nerve fibre

• neurotransmitters are released by dendrites and not by axon endings

• neurotransmitters are released by the axon endings and not by dendrites.

Pacinian corpuscles occur in the skin of certain parts of body in mammals. These are

• type of glands

• pain receptors

• naked tactile receptors

• encapsulated pressure receptors.

Wharton's duct is the duct of

• submandibular salivary gland

• parotid gland

• sublingual gland

• all of these

The checkpoint in cell cycle plays important role in

• repairing DNA damage

• apoptosis initiation

• assessing DNA damage

• none of these

C₄ plants have better productivity because

• C₄ plants absorb more light

• C₄ plants absorb more CO₂

• C₄ plants lack photorespiration

• all of these