Kidney Functions and Mechanisms of Urine Formation

Flashcards covering kidney functions, nephron structure, glomerular filtration, tubular reabsorption, secretion, and GFR regulation.

Kidneys cleanse blood and adjust its composition by regulating water volume and __ concentration.

solute

The endocrine functions of the kidneys include the production of Renin, which plays a role in the regulation of __.

blood pressure

__ are the structural and functional units of the kidney that form urine.

Nephrons

The two main parts of a nephron are the renal corpuscle and the __.

renal tubule

The renal corpuscle consists of the glomerulus and __.

Glomerular capsule

The ascending and descending limbs are parts of the __.

Nephron loop

The __ is lined with cuboidal cells that possess dense microvilli, which increase surface area.

proximal convoluted tubule (PCT)

The __ functions more in secretion than reabsorption and is confined to the cortex of the kidney.

distal convoluted tubule (DCT)

__ cells, found in collecting ducts, play a role in the maintenance of acid-base balance.

Intercalated

__ nephrons make up 85% of nephrons, while juxtamedullary nephrons are important in the production of concentrated urine.

Cortical

The renal tubules of each nephron is closely associated with two capillary beds: the glomerulus, and the __.

peritubular capillaries

The __ arteriole enters the glomerulus, and blood leaves via the efferent arteriole.

afferent

Peritubular capillaries arise from efferent arterioles and empty into __.

venules

The juxtaglomerular complex (JGC) is important in regulating rate of __ formation and blood pressure.

filtrate

__ cells in the JGC act as chemoreceptors that sense NaCl content in filtrate entering the DCT.

Macula densa

__ cells in the JGC act as mechanoreceptors that sense blood pressure in the afferent arteriole and secrete renin in response to low blood pressure.

Granular

Three major renal processes that adjust plasma composition are glomerular filtration, tubular reabsorption and __.

tubular secretion

Glomerular filtration is a passive process driven by hydrostatic __.

pressure

The chief force pushing water and solutes out of the blood in the glomerulus is hydrostatic pressure in glomerular __.

capillaries (HPGC)

The sum of outward and inward pressures in the glomerulus determines the net __ pressure.

filtration

If GFR increases, filtrate flow rate will increase leading to decreased reabsorption time, causing high __ levels in filtrate.

NaCl

Volume of filtrate formed per minute by both kidneys defines the glomerular __ rate (GFR).

filtration

The kidney can maintain a constant GFR by adjusting its own __ to blood flow.

resistance

The myogenic mechanism and tubuloglomerular feedback mechanism are two types of renal __.

autoregulation

Aldosterone and Atrial Natriuretic Peptide are __ that play a role in reabsorption.

hormones

In the transcellular route, solute enters apical membrane of tubule cells, travels through cytosol of tubule cells, exists basolateral membrane of tubule cells and finally enters blood though endothelium of __ capillaries.

peritubular

In tubular reabsorption, substances can follow two routes: transcellular and __.

paracellular

The reabsorption of water occurs by osmosis into peritubular capillaries and is aided by transmembrane proteins called __.

aquaporins

ADH prompts cells of collecting ducts to insert __ into their apical membranes allowing for water reabsorption.

aquaporins

ADH is released by the __ pituitary gland.

posterior

Aldosterone targets collecting ducts and distal DCT, promoting the reabsorption of __ and therefore water.

sodium

The tubular secretion is important for disposing of substances such as __.

drugs

The renal tubule and collecting ducts are responsible for reabsorption and __.

secretion

The countercurrent multiplier depends on actively transporting __ out of the ascending limb.

solutes