Flashcards in Renal System Deck (62):
What is Kidney
Urine production site
What is the passage of urine to bladder
Function of bladder
What is the exit of urine
Role of the renal system
~ Maintain the balance of water, electrolytes, acid/ base homeostasis
~ Elimination of water soluble waste products
~ Regulate the osmotic balance of plasma --> maintain other blood fluid as well
~ Regulate blood volume, composition &pH
~ Removal/ restoration of : H2O/ Potassium/ Sodium/ Chloride/ H+/ HCO3-/ Calcium/ Sulphate/ Phosphate
~ Regulate arterial blood pressure
~ Elimination of waste products of metabolism - especially nitrogen- containing molecules UREA & CREATININE
~ Elimination of foreign chemical and pollutants
~ Metabolism functions
What are the metabolism functions of the renal system
~ Synthesis Renin (an enzyme secrete into blood by kidney) > involved in control of blood pressure and fluid balance
~ Synthesis Vitamin D > (regulation of calcium in body) is converted to its active form in the body
~ Synthesis Erythropoietin > stimulate RBC production --> affects blood oxygen carrying capacity
Where is the kidney located?
What does it looks like?
Pair of bean shaped organs
located in the abdominal cavity; held firm in position, usually embedded in fat, protected with connective tissue
Which vessels supply blood to kidney?
Renal arteries, renal veins
How much blood does the kidney receive?
25% of the cardiac output
How many time does the body total volume of blood circulated through the kidneys IN A DAY?
Kidney has a ______ structure
Draw and name different regions of the kidney
- Renal cortex
- Renal medulla
- Major calyx/ Minor calyx
- Renal pelvis
- Renal papilla
- Renal pyramid
- (Ureter, renal artery, renal vein)
What is the functional unit of the kidney?
How many is there?
Nephron , 1- 2 million
Nephrons start in the _____ ____, travel down into _______ _____ and back up to the ______
Renal cortex, renal medulla , cortex
Each lobe of kidney consist of _______ which opens into a branch from the ______
a renal pyramid, ureter
Each nephron consists of ....
a renal tubule & a renal corpuscle
Name different regions of the renal tubule
@ Proximal convoluted tubule
- Proximal straight tubule
@ Descending limb of loop of Henle
@ Thin ascending limb of loop of Henle
@ Thick ascending limb of loop of Henle
@ Distal convoluted tubule
@ Connecting tubule
- Collecting duct
What is renal corpuscle consists of ? and its function
Bowman's capsule & Glomerulus
The renal corpuscle filters plasma
What is Glomerular filtrate?
Filtrate with water and low molecular weight components removed from the plasma, filtered by the renal corpuscle
function of Renal tubule
Selectively reabsorbs water & ions from the glomerular filtrate > the end result is urine production
Proximal convoluted tubule and Distal convoluted tubule lined by different epithelial cells T/F
What cells does the bladder consist?
~ Lined by transitional epithelium ( urothelium) that stratified 3- 6 layers
- basal cuboidal cells
- intermediate columnar cells
- surface umbrella cells (to allow for stretch)
Urine production is a ____ phrase process: ...?
3; filtration > resorption & secretion > excretion
Describe glomerular filtration (ultrafiltration)
- Blood enters the glomerular capillaries and a portion of it enters the Bowman's space.
- The glomerular filtrate contains water and small solutes ( sodium, potassium, chloride, bicarbonate ions)
- Proteins and Blood Cells are prevented from passing into the Bowman's space
What is prevented from entering the Bowman's space during the glomerular filtration? and HOW?
Protein - prevented by their negative charge repelling with carbohydrates
and their sizes
Blood cells - prevented by their sizes
What is filtration fraction ?
The fraction of blood plasma flowing through the nephron that is actually filter across the glomerular membrane
The filtration fraction is depends on ...?
Glomerular filtration rate (GFR) ÷ Renal Plasma Flow (RPL)
The usual filtration fraction is ...?
Why is renal system important?
- Brain will shrink if dehydrated
- Tissue will swell if the water level is unbalanced
- Electrolytes level balance is important for liver
- Blood pressure is affected by kidney
If the body don't have enough water, how would the water level be regulated
The water in the blood will filter back into blood
What is Urea?
The waste product of protein metabolism. A nitrogen containing organic compound
What is creatinine
A waste product generated from muscle metabolism, created by creatin from the energy production of muscles
Describe renal corpuscle and what happen there?
A capsule and a rubber band ball of blood vessels. Blood is removed from vessels, plasma is filtered and send back to blood stream. The complex network gives large surface area
Amino acid can't pass through gap of cells at the renal corpuscle T/F
It can as it is small enough, but big size protein can't
Why is the bladder lined by __________?
Because urine can be very concentrated, it would inflame the tissue if it's lined by simple epithelium
Glomerular filtration rate is normally ...ml/ min
urine production is ...ml/ min
How much urine is produced per day
~ 125 ml/ min
~ 1 ml/ min
under 1.5 L per day
What are involved in renal of resorption and their %
glucose - 100%
sodium - 99%
Water - 99%
Calcium - 96%
Potassium - 94%
Urea - 42%
If the urine glucose level is high, it may be ...
If the urine protein level is high, it may be ...
High blood pressure
Resorption begins in which region?
proximal convoluted tubule
epithelial cells of nephron wall absorbed small proportion of the filtrate T/F
It re- absorbs large proportion of filtrate (~2/3)
What filtrate content will be re-absorbed?
glucose, water, bicarbonate, 2/3 of the sodium, amino acids
Resorption is passive transport because of osmosis T/F
It is a active transport as it is against a concentration gradient
The resorption is helped by _______ ________ on the epithelial cells
Why is sodium resorption/ sodium balance important?
- Na+ is the major cation in the plasma and interstitial fluid.
- Na+ in the extracellular fluid determine the extracellular fluid volume > which determines the plasma volume and blood volume > affects the blood pressure
- Kidney has to make sure the Na+ intake = Na+ excretion (Sodium level is balance)
Describe how sodium been reabsorbed in the loop of Henle
- Water travel down the descending limb of loop of Henle and move out the tubule by osmosis.
- Thin ascending limb loop of Henle is permeable to Na+ & Cl - . They moved out the tubule by diffusion down a concentration gradient
- Thick ascending limb loop of Henle is impermeable to Na+ & Cl- . The solute have to move out by active transport.
The filtrate at the thin descending loop of Henle is hypotonic to the blood. Filtrate(water, Na+ & Cl-) moves into tubule by active transport as the membrane is permeable T/F
The filtrate is hypotonic to blood
Only WATER moves out to the blood by OSMOSIS
The membrane is permeable to water, but impermeable to the solutes.
The filtrate at the thin ascending loop of Henle is impermeable to Na+ & Cl-. Hence they have to move out by active transport T/F
The membrane is permeable to Na+ & Cl-. They moved out by DIFFUSION down a concentration gradient
The filtrate at the thick ascending loop of Henle is hypertonic to the blood. Filtrate(water, Na+ & Cl-) moves into tubule by active transport as the membrane is impermeable T/F
The filtrate at the thick ascending LoH is very hypotonic.
Only Solute move out of the tubule by active transport because the membrane is IMPERMEABLE to WATER
Net result of Na+ resorption at the loop of Henle?
remaining 8% reabsorbed at the distal convoluted tubule and collecting duct
The amount of extracellular fluid and sodium in the body is reflected on ........
the volume of urine
which endocrine glands and which hormone involve in the regulation of fluid balance within the body? How?
~ Adrenal gland > secrete aldosterone > less water excreted in the urine
~ Pituitary gland - posterior pituitary gland > secrete anti- diuretic hormone (ADH) > distal convoluted tubule and collecting duct become more permeable to water > more water reabsorbed
How does reducing the urine production balance the Na+ level?
~ High Na+ level detected by the brain
~ Pituitary gland send out the anti diuretic hormone via blood to kidney
~ Kidney reabsorbed more water into the blood stream to dilute the Na+ concentration
~ Lower Na+ lv and back to normal
~ As result, less urine is produced.
Secretion of H+ is important in .....
Controlling the blood pH
H+ and K+ are secreted into the blood OR tubule fluid?
At which region ?
secreted into the fluid
within the distal convoluted tubule and collecting duct
What is tubule secretion?
Molecule been removed from blood and transferred into the tubule fluid WITHIN the tubules
What is kidney stone?
~ A crystal aggregation formed within the kidney from the dietary mineral in the urine.
~ It is formed when the urine volume has decreased or there's an excessive amount of dietary mineral in the urine
~ Symptoms include flank pain and blood in urine
Role of liver in detoxification
~ To covert ammonia (NH3), the waste of amino acids metabolism, into urea (H2NCONH2) which then can be excreted in urine
~ Directly enzymatic neutralisation of toxin
~ Modification of toxins to form activated intermediates (products of conversion), which then can be neutralised by additional enzyme system. E.g. alcohol metabolism
What is deamination?
Removing an amino group from a molecule
Dietary amino acids can be converted to _______ or ________, by ....
convert to fat storage / convert to glucose by gluconeogenesis
by removing the nitrogen containing amino group (deamination)
What is the result of dietary amino acids deamination
Ammonia (NH3), which is highly toxic