chapter 48 ~ urinary system Flashcards
The regulation of water and ion balance.
Osmoregulation
The process by which the fluid containing waste materials —urine— is released from the body into the environment from the distal end of an excretory tubule.
Excretion
The total solute concentration of a solution, measured in is moles— the number of the solute molecules and ions (in moles) — per liter of solution.
Osmolarity
The control of body temperature.
Thermoregulation
An animal that uses control mechanisms to keep the osmolarity of cellular and extracellular fluids the same, but at levels may differ from the osmolarity of the surroundings.
Osmoregulators
A layer of cells with specialized transport proteins in their plasma membranes.
Transport epithelium
An animal in which the osmolarity of the cellular and extracellular solutions matches the osmolarity of the environment.
Osmoconformers
Minute tubular structures that carry out osmoregulation and excretion.
Excretory tubules
The outer region of the mammalian kidney that surrounds the renal medulla.
Renal cortex
The main organ of excretion and osmoregulation in insects, helping them to maintain water and electrolyte balance.
Malphighian tubule
The inner region of the mammalian kidney.
Renal medulla
The simplest form of invertebrate excretory tubule.
Protonephridium
A specialized excretory tubule that contributes to osmoregulation and carries out excretion, found in all vertebrates.
Nephrons
An artery that carries bodily fluids into the kidney.
Renal artery
A storage sac located outside the kidneys.
Urinary bladder
The vein that routes filtered blood away from the kidney.
Renal vein
The central cavity in the kidney where urine drains from collecting ducts.
Renal pelvis
The tube through which urine flows from the renal pelvis to the urinary bladder.
Ureter
In mammals, the kidneys and ureters, the bladder, and the urethra.
Urinary system
A location where urine leaving individual nephrons is processed further.
Collecting ducts
The tube through which urine leaves the bladder. In most animals, the urethra opens to the outside.
Urethra
A ball of blood capillaries surrounded by Bowman’s capsule in the human nephron.
Glomerulus
The tubule between the Bowman’s capsule and the loop of Henle in the nephron of the kidney, which carries and processes the filtrate.
Proximal convoluted tubule
The process by which plasma filters through the glomerular capillaries into Bowman’s capsule as blood flows through the glomerulus; it is the first step of urine formation
Glomerular filtration
An infolded region at the proximal end of a nephron that cups around the glomerulus and collects the water and solutes filtered out of the blood.
Bowman’s capsule
The vessel that delivers blood to the glomerulus of the kidney.
Afferent arterioles
The tubule in the human nephron that drains urine into a collecting duct that leads to the renal pelvis.
Distal convoluted tubule
A u-shaped bend of the proximal convoluted tubule.
Loop of henle
A capillary of the network surrounding the glomerulus.
Peritubular capillaries
The arteriole that receives blood from the glomerulus.
Efferent arteriole
A structure in the kidney near a point where the distal convoluted tubule contracts the afferent arteriole carrying blood to the glomerulus; specialized tubule cells in the _________ monitor the salt level of the fluid flowing past them in the tubule.
Juxtaglomerular apparatus
In the renin-angiotensin-aldosterone system (RAAS), the enzyme that converts angiotensin I to angiotensin II.
Angiotensin-converting enzyme (ACE)
In the renin-angiotensin-aldosterone system (RAAS), the molecule produced by cleavage of the plasma protein angiotensinogen.
Angiotensin I
An enzyme secreted by cells in the juxtaglomerular apparatus into the bloodstream that converts a blood protein into the peptide hormone angiotensin.
Renin
The most important hormonal system involved in regulation of NA+ in mammals.
Renin-angiotensin-aldosterone system (RAAS)
In the renin-angiotensin-aldosterone system (RAAS), the molecule converted from angiotensin I by angiotensinconverting enzyme (ACE); angiotensin II is a hormone that constricts arterioles to raise blood pressure, stimulates synthesis of aldosterone and its secretion from the adrenal cortex, and stimulates thirst.
Angiotensin II
A hormone secreted by the posterior pituitary that increases water absorption in the kidneys, thereby increasing the volume of the blood.
Antidiuretic hormone (ADH)
A mineralocorticoid hormone released from the adrenal cortex increases the amount NA+ reabsorbed from the urine in the kidneys and absorbed from foods in the intestine, reduces the amount of NA+ secreted by salivary and sweat glands, and increases the rate of K+ excretion by the kidneys, keeping NA+ and K+ balanced at the levels required for normal cellular function.
Aldosterone
The flow of heat between atoms or molecules in direct contact.
Conduction
A sensory neuron in the hypothalamus that responds to changes in the osmolarity of the fluid surrounding it, which reflects the osmolarity generally of the body fluids.
Osmoreceptor
A peptide hormone that inhibits renin release and increases the filtration rate by dilating the arterioles that deliver blood to glomeruli and by inhibiting aldosterone release.
Atrial natriuretic factor (ANF)
The transfer of heat energy as electromagnetic radiation.
Radiation
The transfer of heat from a body to a fluid, such as air or water, that passes over its surface.
Convection
An animal that obtains its body heat primarily from the external environment.
Ectotherms
Heat transfer through the energy required to change a liquid to a gas.
Evaporation
An animal that obtains most of its body heat from internal physiological sources.
Endotherms
A set of physiological changes in ectoderm’s in response to seasonal shifts in environmental temperature, allowing the animals to attain good physiological performances at both winter and summer temperatures.
Thermal acclimatization
The temperature within the central core of the body consisting of the abdominal and thoracic organs, the CNS, and the skeletal muscle.
Core temperature
The generation of heat by oxidative mechanisms in non muscle tissue throughout the body.
Non shivering thermogenesis
A specialized tissue in which the most intense heat generation by non shivering thermogenesis takes place.
Brown fat
A specialized tissue in which the most intense heat generation by non shivering thermogenesis takes place.
Brown adipose tissue
A condition in which the core temperature falls below normal for a prolonged period
Hypothermia
Seasonal torpor in an animal that occurs in summer.
Estivation
The innermost layer of the skin that contains larger blood vessels and additional reinforcing connective tissue.
Hypodermis
Extended torpor during winter.
Hibernation
The condition resulting when the heat gain of the body is too great to be counteracted by physiological responses.
Hyperthermia
The skin layer below the epidermis; it is packed with connective tissue fibers such as collagen, which resist compression, tearing, or puncture of the skin.
Dermis
A sleep like state produced when a lowered set point greatly reduces the energy required to maintain body temperature, accompanied by reductions in metabolic, nervous, and physical activity.
Torpor
A period of inactivity and lowered metabolic rate that allows an endotherm to conserve energy when environmental temperatures are low.
Daily torpor
