Kidney Lecture Vocabulary

kidney

produces urine

ureter

transports urine toward the urinary bladder

urinary bladder

temporarily stores urine prior to elimination

urethra

conducts urine to exterior; in males, transports semen as well

outer cortex

the outer layer of the kidney

inner medulla

the inner part of the kidney, consists of the medullary collecting ducts, loops of Henle, vasa recta and the interstitium.

renal pyramids

any of the somewhat triangular- or wedge-shaped masses of tissue, conical, help with blood filtration and water concentration regulation within your kidneys

renal columns

provide passage for blood vessels to extend throughout the renal cortex as they continue towards the renal pyramids, extends from the cortex inwards

renal pelvis

funnel-shaped chamber connected to the ureter, to act as a funnel for urine flowing to the ureter

renal corpuscle

acts to filter blood, cup-shaped chamber

Bowman’s capsule

performs the first step in the filtration of blood to form urine, participates in the filtration of blood from the glomerular capillaries

glomerulus

functional unit for filtration of blood and formation of primary urine, a capillary network

afferent arteriole

to deliver blood to the glomerulus for filtering in the kidney, this is how blood originating from the renal artery reaches the glomerulus

filtration

the process that your kidneys use to filter excess fluid and waste products out of the blood into the urine collecting tubules of the kidney, so they may be eliminated from your body

secretion

waste ions and hydrogen ions pass from the capillaries into the renal tubule, secreted ions combine with the remaining filtrate and become urine

reabsorption

the movement of water and solutes from the tubule back into the plasma

glomerular capillaries

clusters of capillaries that are surrounded by Bowman's capsules and lined with a single layer of epithelial cells called the parietal epithelium

urine

a watery, typically yellowish fluid stored in the bladder and discharged through the urethra. It is one of the body's chief means of eliminating excess water and salt, and also contains nitrogen compounds such as urea and other waste substances removed from the blood by the kidneys

deaminates

to remove the amino group from (a compound)

urea

a water-soluble molecule that is excreted in urine, a colorless crystalline compound which is the main nitrogenous breakdown product of protein metabolism in mammals and is excreted in urine

nephron

the functional unit of the kidney

glomerulus

where blood is filtered across the walls of a knot of capillaries

renal tubule

One of millions of tiny tubes in the kidneys that returns nutrients, fluids, and other substances that have been filtered from the blood, but the body needs, back to the blood

peritubular capillaries

tiny blood vessels in your kidneys, they deliver wastes to be secreted into urine (pee), they also reabsorb nutrients your body needs

countercurrent multiplier mechanism

process of using energy to generate an osmotic gradient that enables you to reabsorb water from the tubular fluid and produce concentrated urine

aquaporins

serve as water channels in the collecting duct cell membranes (apical side)

autoregulatory mechanisms

maintains a constant high glomerular filtration rate even if blood pressure varies, the intrinsic ability of an organ to maintain blood flow at a nearly constant rate despite changes in arterial perfusion pressure

renin

an enzyme secreted by and stored in the kidneys which promotes the production of the protein angiotensin

angiotensin

a protein whose presence in the blood promotes aldosterone secretion and tends to raise blood pressure, causes constriction of peripheral blood vessels

aldosterone

a corticosteroid hormone which stimulates absorption of sodium by the kidneys and so regulates water and salt balance, enhances water reabsorption and stimulates thirst

atrial natriuretic peptide (ANP)

a peptide hormone secreted by myocytes of the cardiac atria that in pharmacological doses promotes salt and water excretion and lowers blood pressure, released by atria of the heart when blood pressure becomes high