NCERT Class 11 Science — Chapter 9: Chemical Coordination and Integration

Assertion (A): Thyrocalcitonin (TCT) helps regulate blood calcium levels. Reason (R): Parathyroid hormone (PTH) acts on bones to stimulate bone resorption.

Which hormone stimulates the synthesis and secretion of milk in the mammary glands?

The interstitial cells (Leydig cells) of the testis secrete:

Which of the following statements about aldosterone is/are correct? 1. It promotes reabsorption of sodium and water in renal tubules. 2. It increases retention of potassium and phosphate ions. 3. It helps in the maintenance of blood pressure. Select the correct answer using the code below:

With reference to parathyroid hormone (PTH), consider the following statements: 1. Its secretion is regulated by circulating sodium levels. 2. It increases bone resorption and renal reabsorption of calcium. 3. It increases calcium absorption from the digested food. Which of the statements given above are correct?

Which pancreatic hormone acts to increase blood glucose levels (hyperglycemia)?

Which of the following correctly describes oxytocin's actions? 1. Stimulates uterine smooth muscle contraction during parturition. 2. It inhibits milk ejection. 3. It primarily contracts smooth muscles. Select the correct answer using the code below:

The innermost layer of the adrenal cortex is the:

Assertion (A): Vasopressin is synthesized by the posterior pituitary gland. Reason (R): Vasopressin stimulates the reabsorption of water and electrolytes by the distal tubules.

Regarding insulin action, which of the following statements is/are correct? 1. It enhances glucose uptake by hepatocytes and adipocytes. 2. It inhibits glycogenesis. 3. It prevents hyperglycemia. Select the correct answer using the code below:

Match the pituitary hormone with its principal action: List I | List II A. Growth hormone (GH) | 1. Stimulates secretion of glucocorticoids B. Prolactin (PRL) | 2. Stimulates synthesis and secretion of thyroid hormones C. Thyroid-stimulating hormone (TSH) | 3. Regulates growth of mammary glands and milk formation D. Adrenocorticotrophic hormone (ACTH) | 4. Stimulates body growth Select the correct answer using the code given below

With reference to hypothalamic control of the pituitary, consider the following statements: 1. Releasing and inhibiting hormones reach the anterior pituitary through a portal circulation. 2. The posterior pituitary is under direct neural regulation of the hypothalamus. Which of the statements given above is/are correct?

Consider the following about acromegaly: 1. It results from excess growth hormone secretion in adults. 2. It is not associated with any physical disfigurement. 3. It is usually easy to diagnose in its early stages. Which of the statements given above is/are correct?

Assertion (A): Gonadotrophin-releasing hormone (GnRH) stimulates the pituitary synthesis and release of gonadotrophins. Reason (R): LH and FSH are produced by the hypothalamus and stored in the anterior pituitary.

Consider the following statements about the thyroid gland: 1. It consists of a single lobe located on the trachea. 2. Follicular cells synthesize thyroxine (T4) and triiodothyronine (T3). 3. Iodine is essential for the normal rate of hormone synthesis. Which of the statements given above are correct?

Which of the following are associated with deficiency of thyroid hormones? 1. Cretinism occurs when deficiency happens in old age. 2. Goitre formation due to iodine deficiency. 3. It ensures perfectly regular menstrual cycles. Select the correct answer using the code below:

Melatonin is known to: 1. Regulate diurnal rhythms such as sleep-wake cycle. 2. Influence body temperature. 3. Affect metabolism and pigmentation. 4. It has no influence on the menstrual cycle. Select the correct answer using the code below:

With reference to glucagon, which of the following is/are correct? 1. It is a peptide hormone. 2. It inhibits glycogenolysis in hepatocytes. 3. It increases cellular glucose uptake. Select the correct answer using the code below:

Consider the following statements about the endocrine pancreas: 1. It comprises Islets of Langerhans numbering about 10 to 20 million. 2. These islets constitute roughly 1 to 2 % of the pancreatic tissue. 3. α-cells secrete glucagon and β-cells secrete insulin. Which of the statements given above are correct?

Consider the following statements regarding spermatogenesis regulation: 1. In males, LH stimulates androgen synthesis from testis. 2. In males, FSH and androgens regulate spermatogenesis. Which of the statements given above is/are correct?

The corpus luteum primarily secretes which hormone essential for the maintenance of pregnancy?

Vasopressin, released by the posterior pituitary, is also known as:

Which endocrine gland is located on the dorsal side of the forebrain?

The pineal gland secretes which hormone that regulates the diurnal (24-hour) rhythm of the body?

The adrenal medulla secretes 'fight or flight' hormones known as:

In humans, the parathyroid glands are typically present as:

Which gland is prominent at birth but gradually atrophies in the adult?

The primary glucocorticoid secreted by the human adrenal cortex is:

Which of the following hormones is chemically classified as a catecholamine?

Assertion (A): The anterior pituitary is directly connected to the hypothalamus by a neural pathway. Reason (R): The posterior pituitary stores and releases hormones actually synthesized by the hypothalamus.

Which of the following are typical effects of catecholamines released from the adrenal medulla? 1. They decrease heart rate and strength of cardiac contraction. 2. Increased alertness and pupillary dilation. 3. Reduced respiratory rate and glycogen synthesis. Select the correct answer using the code below:

Which cells in the testis are responsible for the synthesis and secretion of androgens like testosterone?

The two lobes of the thyroid gland are connected by a thin flap of connective tissue called:

The endocrine portion of the pancreas consists of cell clusters known as:

Regarding exophthalmic goitre (Graves' disease), which of the following is/are correct? 1. It is a form of hyperthyroidism. 2. It involves sinking of the eyeballs. 3. It is characterised by an increased basal metabolic rate. Select the correct answer using the code below: