Human Endocrine System

The pituitary gland produces multiple hormones including growth hormone and ADH, the thyroid gland secretes thyroxine and calcitonin, and ovaries produce estrogen and progesterone. The liver primarily performs metabolic functions like detoxification and protein synthesis, but is not an endocrine organ that secretes hormones.

Oxytocin is the hormone responsible for milk ejection (let-down reflex) during lactation. It causes the muscles around the milk-producing cells to contract, pushing milk into the ducts. Prolactin is responsible for milk production, not ejection. Thyroxine regulates metabolism and testosterone is a male sex hormone.

Cortisol is a stress hormone associated with the body's stress response, not pleasure or reward. Prolactin is primarily involved in lactation and reproductive functions. The other pairs (endorphins/tryptophan, serotonin/dopamine, oxytocin/vasopressin) are all associated with positive feelings or reward mechanisms.

Oxytocin is produced in the hypothalamus and released by the posterior pituitary gland, not the anterior pituitary. The anterior pituitary secretes hormones like Prolactin, FSH, LH, TSH, ACTH, and Growth Hormone. This makes Oxytocin the correct answer to what is NOT secreted by the anterior pituitary.

The correct answer is C. Oxytocin and vasopressin are the two primary hormones associated with love, bonding, and attachment. Oxytocin is often called the 'love hormone' and is released during physical intimacy and social bonding. Vasopressin also plays a role in pair-bonding and attachment behaviors. These neuropeptides are crucial for forming and maintaining emotional connections.

Vitamin C supports adrenal function and cortisol production, helping regulate stress response. Vitamins A, D, and K are essential for other functions (vision, bone health, clotting) but aren't primarily linked to stress hormone release.

Insulin is produced and secreted by the beta cells of the pancreas. Option C is correct.

Insulin is the hormone responsible for maintaining blood sugar levels. Produced by the beta cells of the pancreas, insulin allows cells to take in glucose from the bloodstream for energy production, thereby lowering blood sugar levels. Thyroxine regulates metabolism, and cytokinins are plant hormones, not relevant to human blood sugar regulation.

Activity of osteoclasts is modified by calcitonin and parathormone through receptors on osteoclasts.

Placenta also acts as an endocrine tissue and produces several hormones like human chorionic gonadotropin (hCG), human placental lactogen (hPL), estrogens, progestogens, etc.

Human chorionic gonadotropin (hCG) and human placental lactogen (hPL) are secreted by placenta and relaxin is also secreted by the ovary during later phase of pregnancy.

Iodine is necessary for the secretion of thyroxin.

Nervous system and endocrine system are very closely related because both need stimuli for their action response.

Veins transport hormones from the endocrine gland to various body parts.

Parathormone influences the ossification of bones.