11 NCERT BIOLOGY MOST IMPORTANT QUESTIONS

Q1. A steroid hormone which regulates glucose metabolism is 1) ll-Deoxycorticosterone 2) Corticosterone 3) Cortisone 4) Cortisol Solution Steroids are lipid hormones which are derived from cholesterol. Cortisol is secreted by the middle layer (i.e. zona fasciculata) of the adrenal cortex. Cortisol promotes gluconeogenesis (i.e. the formation of glucose from non-carbohydrates such as proteins). It also stimulates proteolysis and lipolysis. Q2. Diabetes is due to 1) Na + deficiency 2) Hormonal deficiency 3) Enzyme deficiency 4) Iodine deficiency Solution Diabetes mellitus occ

Q1. Which one of the following does not act as a neurotransmitter?   1) Norepinephrine   2) Cortisone   3) Epinephrine   4) Acetylcholine   Solution Cortisone is a hormone released by the adrenal glands.   Q2. Nodes of Ranvier are found in   1) Non-myelinated nerve fibres   2) Myelinated nerve fibres   3) Both 1 and 2 above   4) None of the above   Solution Nodes of Ranvier are found in myelinated nerve fibres. These are the gaps between two adjacent myelin sheaths.   Q3. The area where the medullary sheath is absent in the nerve fibre is called   1) Nissl'