DHUBS1 - week 8 Flashcards
(22 cards)
organs of the urinary tract
kidneys
urinary tract: ureters, urinary bladder and urethra
urination or micronutrition
kidney function
- excretion: removal of metabolic wastes form body fluids
- elimination: discharge of these wastes fomr body
- homeostatic regulation: of volume and soluate concentration of blood
homeostatic functions of the urinary system
- regulating blood volume and blood pressure
- regulating plasma in ion concentrations
- healping to stabilise blood pH
- conserving valuable nutrients
- assisting liver
about the kidneys
bean shaped
retroperitoneal
protected by lower part of rib cage and three layers of supportive tissue
what are the three layers of support tissue in the kidnesy?
- Renal fascia: dense connective tissue – anchor kidneys to surrounding structures
- Perinephric fat capsule: fatty mass protects kidneys from trauma
- Fibrous capsule: transparent layer; protection from infection
about the adrenal glands
two triangle shaped endocrine glads
make hormones: adrenaline, nonadrenaline, cortisol and aldosterone
internal anatomy of kidneys
renal cortex: outer region, contains nephrons
renal medulla: middle region, channels urine to renal pelvis
renal pelvis: inner region, drains urine into ureters
the nephron - fucntional unit of the kidney
Structural and functional unit of kidney
~1 million per kidney
Perform the processes to filter blood plasma and form urine
Consist of:
Renal corpuscle and,
Renal tubule
renal corpuscle
consists of 2 parts
1. Bowmans capsule
2. glomerulus
function: to produce the filtrate, a protein free solution
renal tubule
has 3 main parts
1. Proximal convoluted tubule (PCT)
2. Nephron loop (Loop of Henle)
3. Distal convoluted tubule (DCT)
processes of urine formation
- Glomerular filtration
- Makes a protein-free filtrate that contains water, ions, nutrients and waste products - Tubular reabsorption
- Selective movement of valuable wanted substance from filtrate back into blood
- Glucose, amino acids, 99% of water, salt - Tubular secretion
- Selective movement of some unwanted substances from blood back into filtrate
what is teh pyelogram
x-ray image of the urinary system
what is the glomerular filtration rate (GFR)
= total amount of filtrate that both kidneys produce each minute.
regulation of the glomerular filtration rate (GFR)
Regulated by 2 mechanisms
Ensures…
- adequate blood flow to kidneys
- normal filtration pressures:
- Intrinsic (autoregulation)- acting locally at kidney and involves the nephrons and,
- Extrinsic- acting from a distance e.g. autonomic regulation by sympathetic nerves and hormonal regulation initiated by kidneys
what is filtrate?
= blood plasma minus blood proteins and blood cells
what is urine?
filtrate minus water, nutrientes, essentail ions plus added wastes
renal maintenance of blood pH
if pH drops - kidneys will secrere more H+ and retain more HCO3, to bring bakc blood pH to homeostasis
if pH increases - kidneys will retain more H+ and secrete HCO3- to bring blood pH back to homeostasis
what is erythropoiesis
production of red blood cells (RBC)
renal control of erythropoeisis
Erythropoiesis – production of red blood cells
Stimulated by the hormone erythropoietin (EPO)
Released by kidneys in response to hypoxia
what is hypoxia
decreased oxygen levels in the blood
causes of hypoxia
Decreased RBC numbers due to haemorrhage or increased destruction
Insufficient haemoglobin per RBC
Reduced availability of O2
the production of erythropoeisis (RBC)
ts controlled by a negative feedbakc mechanism
1. decreases oxygen levels in blood (hypoxia)
2. kindey “senses” hypoxia and releases an enzyme: renal erythropoietin factor (REF)
3. REF converts a plasma protein to hormone - erythropoietin
4. EPO stimulates red bone marrow to produce more RBCs to carry more oxygen
5. oxygen levels in blood return to normal
