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Flashcards in Renal System Deck (62):

What is Kidney

Urine production site


What is the passage of urine to bladder



Function of bladder

Storing urine


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?

300 times


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?
(4 types)

~ Lined by transitional epithelium ( urothelium) that stratified 3- 6 layers
~ Consists:
- 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 ...?

~ 20%


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 __________?

Transitional Epithelium
Because urine can be very concentrated, it would inflame the tissue if it's lined by simple epithelium


Glomerular filtration rate is normally min
urine production is 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 ...

Diabetes, pregnancy


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

numerous microvilli


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?

~ 25%
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


Describe alcohol metabolism

It's a multistep process. Alcohol is metabolised by the liver. The metabolic rate is depended on the level of enzyme.
A small amount may remain un-metabolised and can be detected in urine or breath