Term | Definition |
ADH | A pituitary hormone that acts to promote the retention of water by the kidneys and increase blood pressure |
Adrenal Cortex | The cortex of the adrenal gland; secretes corticosterone and sex hormone |
Afferent and Efferent Arterioles | The efferent arteriole carries blood away from the glomerulus. afferent arteriole enters the glomerulus at the vascular pole and divides into capillaries which subsequently merge to form efferent arterioles. |
Aldosterone | Stimulates absorption of sodium in kidneys |
Bowman's Capsule | Stimulates absorption of sodium in kidneys |
Collecting Duct | Participates in electrolyte and fluid balance through re absorption and excretion. |
Glomerulus | A cluster of capillaries around the end of a kidney tubule, where waste products are filtered from the blood. |
Homeostasis | The tendency toward a relatively stable equilibrium between interdependent elements, especially as maintained by physiological processes. |
Hypothalamus | A region of the forebrain below the thalamus that coordinates both the autonomic nervous system and the activity of the pituitary, controlling body temperature, thirst, hunger, and other homeostatic systems, and involved in sleep and emotional activity. |
Kidney | Each of a pair of organs in the abdominal cavity of mammals, birds, and reptiles, excreting urine. |
Loop of Henle | The part of a kidney tubule that forms a long loop in the medulla of the kidney, from which water and salts are resorbed into the blood. |
Metabolic Waste | Substances left over from excretory processes, which cannot be used by the organism, and must therefore be excreted. This includes nitrogen compounds, water, CO2, phosphates, sulfates, etc. |
Nephron | Each of the functional units in the kidney, consisting of a glomerulus and its associated tubule, through which the glomerular filtrate passes before emerging as urine. |
Nitrogenous Waste | Any metabolic waste product that contains nitrogen. Urea and uric acid are the most common nitrogenous waste products in terrestrial animals; freshwater fish excrete ammonia and marine fish excrete both urea and trimethylamine oxide. |
Osmotic Gradient | Differing particle concentrations on the two sides of the membrane. |
Peritubular Capillary Network | Tiny blood vessels that travel alongside nephrons, allowing reabsorption and secretion between blood and the inner lumen of the nephron. |
Posterior Pituitary | he back portion of the pituitary. It secretes the hormone oxytocin which increases uterine contractions and antidiuretic hormone (ADH) which increases reabsorption of water by the tubules of the kidney. |
Pressure Filtration | The process of passing a liquid through a filter. |
Proximal and Distal Convoluted Tubules | The distal convoluted tubule is a portion of kidney nephron between the loop of Henle and the collecting duct system.The proximal tubule is the portion of the duct system of the nephron |
Reabsorption Of Water | Reabsorption or tubular reabsorption is the flow of glomerular filtrate from the proximal tubule of the nephron into the peritubular capillaries, or from the urine into the blood. |
Renal Cortex | The outer part of the substance of the kidney, composed mainly of glomeruli and convoluted tubules. |
Renal Medulla | The renal medulla is the innermost part of the kidney. The renal medulla is split up into a number of sections, known as the renal pyramids. |
Renal Pelvis | The large bony structure near the base of the spine to which the hind limbs or legs are attached in humans and many other vertebrates. |
Selective Reabsorption | The absorption of some of the components of the glomerular filtrate back into the blood as the filtrate flows through the nephrons of the kidney. |
Tubular Excretion | Filtrate enters the loop of Henle ,more wastes from the blood in the peritubular capillaries are added to the filtrate. The wastes are composed of hydrogen ions,ammonium ions,creatinine. |
Urea | A colorless crystalline compound that is the main nitrogenous breakdown product of protein metabolism in mammals and is excreted in urine. |
Ureter | The duct by which urine passes from the kidney to the bladder or cloaca. |
Urethra | The duct by which urine is conveyed out of the body from the bladder, and which in male vertebrates also conveys semen. |
Urinary Bladder | A membranous sac for temporary retention of urine |
Urine | Watery, typically yellowish fluid stored in the bladder and discharged through the urethra. |