Physiology 1021 Study Guide - Midterm Guide: Renal Corpuscle, Renal Pelvis, Renal Calyx

46 views9 pages
Functions of the kidney
- Regulation of extracellular fluid volume and blood pressure
- Regulation of osmolarity
- Maintain ion balance
- Maintain pH
- Excretion of waste
- Production of hormones
- Gluconeogenesis
Kidney Anatomy
- Two bean-shaped kidneys located posteriorly to the abdomen at the level of the 11th
and 12th ribs
- Retroperitoneal
- Blood enters and exits via the renal artery and renal vein on the inner concave side
- Urine exits via the ureter
- Major calyces large funnel-shaped structures that collect processed fluid from the
minor calyces, which fit over pyramid-shaped segments of nephrons
- Calyces are in the medulla, and organized radically around the renal pelvis
- Cortex tissue that lies on top of the medulla, the outermost tissue of the kidney
- Minor calyces major calyces renal pelvis urine
The nephron
- The functional unit of the kidney
- Each kidney has about one million nephrons
- Made of two structures renal corpuscle and tubule
- Tubule is made of a single layer of epithelial cells
- Two types of nephrons categorized based on position and looks
- Humans have more cortical than juxtamedullary (80%)
- The more juxtamedullary that a species has, the better they are at producing
concentrated urine
- Juxtamedullary conserve water
- Juxtamedullary longer loop of Henle, sits closer to medulla
- Cortical shorter loop of Henle, sits closer to surface
Renal corpuscle
- Filters blood and produces ultrafiltrate
- Found in the cortex
- Made of Bowman’s capsule and glomerulus
- Bowman’s capsule – fluid-filled hollow structure that surrounds the glomerulus,
continuous with proximal tubule
- Cells that make up Bowman’s capsule are called simple squamous epithelial cells
- Podocytes cells that physically connect Bowman’s capsule with the glomerulus
Unlock document

This preview shows pages 1-3 of the document.
Unlock all 9 pages and 3 million more documents.

Already have an account? Log in
JGA
- Composed of the junction of a part of the late ascending limb of the loop of Henle that
passes between the afferent and efferent arteriole
- Macula densa cells specialized cells in the late ascending limb, detect the sodium and
chloride concentrations in the filtrate
- Juxtaglomerular cells responsible for producing and releasing renin
- Glomerulus capillary bed that lies inside Bowman’s capsule. Contains many pores,
making it very leaky
- Basal lamina composed of collagens and glycoproteins
Barriers to filtration
- Size of pores of glomerulus
- Basal lamina
- Size of slits between podocytes
Kidney blood flow
- Kidneys receive 20% of total cardiac output
- Renal artery afferent arteriole glomerulus efferent arteriole peritubular
capillaries venule renal vein
- 2 capillary beds for filtration and reabsorption
- 1 arteriole before and after capillary bed
Processes of the kidney
- Filtration
- Reabsorption
- Secretion
- Amount excreted = amount filtered amount reabsorbed + amount secreted
Net filtration pressure
- The ability to produce large volumes of filtrate are due to net filtration pressure
- Proper filtration can occur if the net filtration pressure is ~10mmHg
- If net filtration is positive, plasma will filter into Bowman’s space
- If net filtration is zero or less, plasma will not filter into Bowman’s space
- If net filtration pressure is more than 10, more will filter in
- Influenced by flow of blood and blood pressure (proportional)
Hydrostatic pressure of glomerular capillaries (PGC)
- Pressure caused by blood flowing into the glomerulus
- Promotes filtration
- 55mmHg
Colloid osmotic pressure of glomerular capillaries (GC)
- Pressure caused by the presence of proteins in the glomerulus
- Inhibits filtration
- 33mmHg
Unlock document

This preview shows pages 1-3 of the document.
Unlock all 9 pages and 3 million more documents.

Already have an account? Log in
Hydrostatic pressure of Bowman’s capsule (PBC)
- Pressure caused by filtrate remaining in Bowman’s space
- Inhibits filtration
- 15mmHg
Colloid osmotic pressure of Bowman’s capsule (BC)
- Pressure caused by the presence of proteins in Bowman’s capsule
- Promotes filtrate
- 0mmHg
(PGC + BC) - (PBC +GC)
Glomerular filtration rate (GFR)
- Amount of fluid that filters per unit of time into Bowman’s space from the glomerular
capillaries
- Influenced by net filtration pressure and filtration coefficient
- Filtration coefficient influenced by surface area of glomerular capillaries and
permeability between them
- The higher GFR, the more solutes excreted
- Regulated by 2 auto-regulatory systems
Myogenic response
- Afferent arteriole stretches
- Stretch-sensitive ion channels open
- Smooth muscle cell depolarizes
- VG calcium channels in smooth muscle open
- Smooth muscle of afferent arteriole contracts
- Blood flow decreases in glomerulus
Tubuloglomerular feedback
- GFR increases
- Flow through tubule increases
- Flow past macula densa increases
- Paracrine from macula densa to afferent arteriole
- Afferent arteriole constricts
- Resistance in afferent arteriole increases
- GFR increases
Regulation by blood flow
- Afferent arteriole constricts GFR decreases
- Afferent arteriole dilates GFR increases
- Efferent arteriole constricts GFR increases
- Efferent arteriole dilates GFR decreases
Measuring GFR
- Analyze creatinine or inulin in urine
[X]urine x urine per day / [X]plasma
Unlock document

This preview shows pages 1-3 of the document.
Unlock all 9 pages and 3 million more documents.

Already have an account? Log in

Document Summary

Regulation of extracellular fluid volume and blood pressure. Two bean-shaped kidneys located posteriorly to the abdomen at the level of the 11th and 12th ribs. Blood enters and exits via the renal artery and renal vein on the inner concave side. Major calyces large funnel-shaped structures that collect processed fluid from the minor calyces, which fit over pyramid-shaped segments of nephrons. Calyces are in the medulla, and organized radically around the renal pelvis. Cortex tissue that lies on top of the medulla, the outermost tissue of the kidney. Minor calyces major calyces renal pelvis urine. Each kidney has about one million nephrons. Made of two structures renal corpuscle and tubule. Tubule is made of a single layer of epithelial cells. Two types of nephrons categorized based on position and looks. Humans have more cortical than juxtamedullary (80%) The more juxtamedullary that a species has, the better they are at producing concentrated urine.

Get access

Grade+
$10 USD/m
Billed $120 USD annually
Homework Help
Class Notes
Textbook Notes
40 Verified Answers
Study Guides
Booster Classes