All MCQs

Thyroid hormones increase metabolic activity in many tissues. This can help regulate energy use, growth, and heat production.

Some hormones are derived from amino acids. Thyroxine derives from tyrosine with iodine, and adrenaline is a catecholamine.

Growth hormone promotes body growth through effects on tissues and growth factors. Deficiency during development can reduce normal growth.

Gonads produce sex steroids that regulate reproductive organs, secondary sexual traits, cycles, and behavior.

Rising osmolarity stimulates ADH release, leading to increased kidney water reabsorption and more concentrated urine.

Low insulin reduces glucose uptake and storage, causing blood glucose to rise. Long-term imbalance affects metabolism and tissues.

Exocrine glands use ducts to deliver secretions to body surfaces or cavities. Endocrine glands are ductless and release hormones internally.

Steroid hormone-receptor complexes often bind DNA or influence transcription. This can lead to slower but longer-lasting physiological changes.

Water-soluble peptide hormones typically bind cell-surface receptors. Second messengers carry the signal inside the cell to produce a response.

Because hormones circulate, they can reach multiple tissues. Only cells with matching receptors respond, allowing broad but selective coordination.

Endocrine axes often involve hypothalamus, pituitary, and a target gland. The final hormone provides feedback to regulate further secretion.

Excess hormone can overstimulate target tissues and disturb homeostasis. The exact effect depends on the hormone, receptor distribution, and feedback control.