Lecture 15 - Micturition Flashcards
Filling of the bladder produces a signal via the pudendal nerve, resulting in ______
inhibition of the external urinary sphincter (pudendal n. is somatic and therefore voluntary)
Cortex of the brain will stimulate the micturition reflex, and inhibit the ______
external urinary sphincter
How do nephrons regulate acid-base balance?
A. Secretion of hormones that change afferent arteriole size, leading to increased acid/base excretion
B. Excrete acids (specificially sulfuric and phosphoric acids)
C. Secrete vasoactive factors to regulate blood flow, thereby changing excretion rates
B. Excrete acids
Kidneys produce what two major hormones?
Erythropoietic, and 1,25-dihydroxycalciferol (Vit D3)
What is the formula for the urinary excretion rate?
Filtration-reabsorption+secretion
Movement of solutes from the Glomerulus to the Bowman's capsule A. Filtration B. Reabsorption C. Secretion D. Excretion
A. Filtration
Solutes not initially filtered, but are placed into the filtrate from the blood. A. Filtration B. Reabsorption C. Secretion D. Excretion
C. Secretion
Removal of filtrate from the nephron A. Filtration B. Reabsorption C. Secretion D. Excretion
D. Excretion
Movement of filtered solutes back into blood. A. Filtration B. Reabsorption C. Secretion D. Excretion
B. Reabsorption
Glomerular hydrostatic and Glomerular osmotic pressure determines GFR. What else is a determinant of GFR?
Kf
The three components of the glomerular capillaries contain (positive/negative) charges.
negative
This is a change of nephron function before histological changes. It is due to loss of basement membrane (-) charges, resulting in proteinuria.
Minimal change nephrophathy
Four factors affecting GFR.
Glomerular hydrostatic P
Bowman’s hydrostatic P
Glomerular oncotic P
Bowman’s oncotic P
GFR of a normal, adult male
180 L/day
Dilation of the renal pelvis and calyces
Hydronephrosis
Filtration fraction is defined as _______.
GFR/renal plasma flow
Increasing the filtration fraction also increases the _____ oncotic pressure.
glomerular
Increased arterial pressure will (increase/decrease) GFR
increase
Increased afferent arteriolar resistance will (increase/decrease) GFR
decrease
Increased efferent arteriolar resistance will (increase/decrease) GFR
increase
Formula for renal blood flow
(Renal arterial P-Renal vein P)/TVR
Sympathetic activation will (increase/decrease) GFR.
decrease; the SNS will constrict the arterioles, and decrease blood flow to kidneys
Angiotensin preferentially constricts ____ arterioles.
efferent
Autoregulation acts to prevent (small/large) changes to GFR that would normally occur even with small blood pressure changes.
large
The juxtaglomerular complex acts to control ______.
the dilation of afferent and efferent arterioles
Reabsoprtion of NaCl in the _____ stimulates the juxtaglomerular complex
ascending limb of loop of Henle
Decreased macula densa [NaCl] will result in ____ to afferent arterioles and release of _____ from JG cells.
dilation; renin
Bladder stretch receptors send signals to the sacral region of the SC via ______, and the signals are conducted back to the bladder via _______.
pelvic nerves;
parasympathetic nerves
What are the mechanisms by which the kidney affects arterial blood pressure?
- Short term - excrete sodium and water
- Long term - secrete hormones and vasoactive factors
