What are the functions of the kidneys?
- FILTER blood plasma (separate and eliminate wastes)
- REGULATE BV, BP, osmolarity of body fluids.
- SECRETE renin and erythroproteins
- DETOXIFY free radicals, drugs
- SYNTHESIZE glucose during starvation
Nitrogenous Wastes
What 4 Metabolic wastes are produced in the body?
NH3, Urea, Uric Acid, Creatinine
What is excretion?
The separating and eliminating of wastes.
What are the 4 systems of the body that use excretion?
Respiratory System
Integument System
Digestive System
Urinary System
What does the Respiratory system excrete?
CO2 (ph) and H2O
What does the Integument system excrete?
Urea, lactic acid, H2O, and salts
What does the Digestive system excrete?
Cholesterol, bile pigments, H2O, and eliminates food wastes
What does the Urinary system excrete?
Metabolic wastes, hormones, drugs, toxins, H2O, H+, and salts
What is included in the gross anatomy of the kidney?
- Renal fascia- anchors kidneys dorsally and ventrally
- Perirenal fat capsules- cushions and supports kidney
- Fibrous Capsule- tightly adhered to kidney
- Cortex-outer 1cm
- Medulla-inner; organized into pyramids and columns
What is the pathway from pyramids to ureter?
Pyramids drain into papilla duct~minor then major calices~renal pelvis~ureter
What are the 11 pathways the renal artery supplies?
- Segmental arteries
- Interlobar arteries
- arcuate arteries
- interlobular arteries
- afferent arteriole (wide)
- glomerulus(site of filtration)
- efferent arteriole (narrow)
- both arterioles from the juxtaglomerular appertus
- peritubular capillaries - in cortex
- vasa recta - in medulla
- –renal vein
What does the renal corpuscle consist of and what is its function?
the glomerulus and glomerular capsule.
Function: filtration
The renal tubule is divided into what 4 regions? What are their functions?
- Proximal Convoluted Tubule (PCT)
function: reabsorption - Nephron Loop
function: create concentration gradient in medulla - Distal Convoluted Tubule (DCT)
function: reabsorption/secretion - Collecting Duct
function: concentration of urine
What is the flow of fluid from where the glomerular filtrate is formed to where urine leaves the body?
Glomerular capsule–>proximal convoluted tubule–> nephron loop–> Distal convoluted tubule–> collecting duct–> papillary duct–> minor calyx–> Major calyx–> renal pelvis–> ureter–> urinary bladder–> urethra
What are Cortical nephrons?
short nephron loops (85%)
What are Juxtamedullary nephrons?
long nephron loops
Around each renal artery is a _____?
Renal plexus
When is renin secretion stimulated?
when BP is low
What are the 3 simple steps of Urine Formation?
- Glomerular filtration
- Tubular Reabsorption and Secretion
- Water Conservation
Fenestrated endothelium of the capillary, Basement membrane and filtration slits are the 3 barriers of what membrane?
the filtration membrane
On average, people produce how much urine per day?
1-2L
If GFR (glomerular filtration rate) is too high, then ____.
filtration increases,
urine increases
=dehydration
If GFR (glomerular filtration rate) is too low, then _____.
filtration decreases,
urine dereases,
=reabsorption of wastes
Which homeostatic mechanism has the ability of the nephrons to adjust their own blood flow and GFR without ecternal control?
Renal autoregulation
