Control of the Internal Environment

These flashcards cover key terms and concepts related to the control of the internal environment, focusing on hormones, the kidneys, and urine formation.

Hormones

Organic chemicals produced in endocrine glands, released into the blood, and responsible for chemical control in animals.

Endocrine Glands

Glands that secrete hormones directly into the bloodstream.

Second Messenger

A substance that transmits signals from a hormone binding to a receptor on the cell membrane to initiate a cellular response.

Cyclic AMP (cAMP)

The most common second messenger formed from ATP, which activates other chemicals and enzymes within the cell.

Steroid Hormones

Lipid-soluble hormones (e.g., oestrogen, testosterone) that can cross cell membranes and directly influence gene expression.

Nephron

The functional unit of the kidney responsible for urine formation.

Ultrafiltration

The process by which small molecules are forced out of the blood and into the Bowman's capsule of the nephron.

Deamination

The process of removing the amino group from amino acids, resulting in the formation of ammonia.

Urea

The less toxic product of ammonia, which is excreted in urine.

Glomerulus

A network of capillaries in the nephron where ultrafiltration occurs.

Afferent Arteriole

The blood vessel that supplies blood to the glomerulus.

Efferent Arteriole

The blood vessel that carries blood away from the glomerulus after filtration.