FREE NEET Biology Practice MCQ Test: Chemical Coordination And Integration Exercise 1 Questions Answers With Detailed Explanations [PDF]

Answer: (a)

Leydig (interstitial) cells in the inter-tubular spaces are stimulated to secrete male sex hormone called androgens (mainly testosterone), under the influence of ICSH of anterior pituitary.

Answer: (b)

Insulin is a peptide hormone, secreted by the β cells of the islets of Langerhans in the pancreas. It plays a major role in the regulation of glucose homeostasis.

Answer: (d)

Answer: (d)

Answer: (d)

Answer: (b)

"Upregulation" of hormone receptors on a cell is the production of more receptors when the hormone is present over time in the blood or other fluids surrounding the cell.

Answer: (a)

Answer: (c)

Answer: (a)

Due to deficiency of ADH water absorption by kidney tubules is decreased leading to excessive urine formation e. diuresis, so the person feels thirsty due to dehydration.

Answer: (a)

Because adrenal medulla is a modified sympathetic ganglion of autonomic nervous system. It develops from same embryonic tissue as all other sympathetic ganglia develop.

Answer: (d)

Anterior lobe of pituitary secretes follicle stimulating hormones, growth hormone and luteinizing hormone.

Answer: (b)

Answer: (b)

Answer: (d)

Answer: (b)

• Growth hormone secreted by anterior pituitary
• Corpus leutum secreted progesterone
• Oxytocin is secreted by posterior pituitary

Answer: (a)

Answer: (d)

Adrenaline is the hormone secreted by adrenal medulla. It prepares the animal to face special conditions created by physical stress. All these conditions require more energy which is provided by increasing heartbeat, blood pressure, respiratory rate, sugar level of blood, blood supply of heart and skeletal muscles and brain through dilation of their small arteries, and oxidative metabolism. It also stimulates the breakdown of liver and muscle glycogen (glucogenesis) to provide glucose for respiration.

Answer: (b)

Tryptophan is an essential amino acid which is precursor for the synthesis of melatonin and serotonin.

Answer: (d)

Secondary messengers are low-weight diffusible molecules that are used to relay signals within a cell. They are synthesized or released by specific enzymatic reactions, usually as a result of an external signal that is received by a transmembrane receptor. cAMP, cGMP and $Ca^{2+}$ act as secondary messengers and are located within the cytoplasm. Sodium is an essential nutrient which helps to maintain blood volume and keeps nerves functioning.

Answer: (d)

Releasing and inhibiting factors are released by hypothalamus. The hypothalamus is connected to adenohypophysis by hypophysial portal vein and is connected to the neurohypophysis by axons of neurosecretory cells. Hence, neurohypophysis is directly under the neural control.