12.2The human Kidney12.2The human Kidney

Mrs. JackieMrs. Jackie

IntroIntro

Human possess two kidneys Human possess two kidneys Situated at the back of the abdominal Situated at the back of the abdominal

cavitycavity Each kidney is connected to a tube Each kidney is connected to a tube

called the ureter which empties into the called the ureter which empties into the urinary bladderurinary bladder

Each kidney is supply by a renal artery Each kidney is supply by a renal artery which supplies urea and oxygenwhich supplies urea and oxygen

Each is also supply with a renal vein Each is also supply with a renal vein that leaves the kidney with the correct that leaves the kidney with the correct levels of urea, salts and water. levels of urea, salts and water.

Draw the structure of the Draw the structure of the kidneykidney

Include the cortex, medulla, Include the cortex, medulla, pelvis, ureter and renal blood pelvis, ureter and renal blood vessels. vessels.

Intro continuesIntro continues PelvisPelvis

Opens into the ureter which is thin tube that Opens into the ureter which is thin tube that takes urine to the bladdertakes urine to the bladder

MedullaMedulla Contains parallel tubes that belong to the loops Contains parallel tubes that belong to the loops

of Henle and the collecting ductsof Henle and the collecting ducts CortexCortex

Outer part of the kidney contains the Bowman Outer part of the kidney contains the Bowman capsules, convoluted tubules and glomerulicapsules, convoluted tubules and glomeruli

Renal vein Renal vein Rich in CO2Rich in CO2

Urinary bladderUrinary bladder Opens into the urethra which empties the urine Opens into the urethra which empties the urine

to the outside of the bodyto the outside of the body Sphincter muscles Sphincter muscles

Guard the emptying of urine Guard the emptying of urine

NephronNephron

It is the functional unit of the It is the functional unit of the kidneykidney

There are about one million in There are about one million in each kindneyeach kindney

Are microscopicAre microscopic

Draw the structure of a glomerulus Draw the structure of a glomerulus and associated nephronand associated nephron

Bowman’s capsule

NephronNephron

Made of the Bowman’s capsuleMade of the Bowman’s capsule Connected to folded tubes called Connected to folded tubes called

convoluted tubules. convoluted tubules. Proximal convoluted tubuleProximal convoluted tubule Distal convoluted tubuleDistal convoluted tubule

Connects with the collecting duct Connects with the collecting duct which pours urine into the pelvis.which pours urine into the pelvis.

Explain the process of ultrafiltration including Explain the process of ultrafiltration including blood pressure, fenestrated blood capillaries blood pressure, fenestrated blood capillaries and basement membraneand basement membrane

Renal artery Renal artery branches inside the kidneybranches inside the kidney A branch enters the bowman’s capsule A branch enters the bowman’s capsule

called the afferent renal arteriolecalled the afferent renal arteriole The arteriole branches into capillaries The arteriole branches into capillaries

called glomerulus inside each capsule.called glomerulus inside each capsule. Capillaries merge again into a blood Capillaries merge again into a blood

vessels that leaves the capsule called vessels that leaves the capsule called the efferent renal arteriole. the efferent renal arteriole.

Explain the process of ultrafiltration including Explain the process of ultrafiltration including blood pressure, fenestrated blood capillaries blood pressure, fenestrated blood capillaries and basement membraneand basement membrane

In the glomerulusIn the glomerulus Blood pressure is highBlood pressure is high Capillaries are between two arteries and Capillaries are between two arteries and

not between artery and veinnot between artery and vein The HBP of capillaries cause fluid to The HBP of capillaries cause fluid to

squeeze out.squeeze out. Only substances that have sizes that Only substances that have sizes that

enable them to pass through enable them to pass through fenestrations (pores) in the capillary wall fenestrations (pores) in the capillary wall can squeeze out.can squeeze out.

This process is called ultra filtration This process is called ultra filtration because is highly selective according to because is highly selective according to the size of the molecules. the size of the molecules.

Explain the process of ultrafiltration including Explain the process of ultrafiltration including blood pressure, fenestrated blood capillaries blood pressure, fenestrated blood capillaries and basement membraneand basement membrane

The filtrate containsThe filtrate contains UreaUrea WaterWater SaltsSalts glucoseglucose

ProteinsProteins Do not filter outDo not filter out Plasma proteins such as albumin, Plasma proteins such as albumin,

globulin and fibrinogen stay inside globulin and fibrinogen stay inside capillaries. capillaries.

UltrafiltrationUltrafiltration

Define osmoregulationDefine osmoregulation

Control of the water balance of Control of the water balance of the blood, tissue or cytoplasm of the blood, tissue or cytoplasm of a living organisma living organism

Explain the reabsorption of glucose, water, Explain the reabsorption of glucose, water, and salts in the proximal convoluted tubule, and salts in the proximal convoluted tubule, including the roles of microvilli, osmosis and including the roles of microvilli, osmosis and

active transport.active transport. Reabsorption depends on the Reabsorption depends on the

Concentration of the substanceConcentration of the substance Structure of the substance Structure of the substance Properties of the endothelial cells Properties of the endothelial cells

that line the cavity of these that line the cavity of these tubules.tubules.

Re absorption in different Re absorption in different parts of the tubulesparts of the tubulesNephron sectionNephron section SubstanceSubstance

Proximal tubuleProximal tubule NaCl by active transportNaCl by active transport

Water by osmosisWater by osmosis

Glucose by active transportGlucose by active transport

Descending part of loop of HenleDescending part of loop of Henle Water by osmosisWater by osmosis

Ascending part of loop of HenleAscending part of loop of Henle Lower section Salts by diffusionLower section Salts by diffusion

Upper section salts by active Upper section salts by active transporttransport

Distal tubuleDistal tubule Water by osmosisWater by osmosis

Collecting ductCollecting duct Depends on hormonesDepends on hormones

ADHADH water levels water levels

Aldoesterone Aldoesterone water levelswater levels

Explain the reabsorption of glucose, water, Explain the reabsorption of glucose, water, and salts in the proximal convoluted tubule, and salts in the proximal convoluted tubule, including the roles of microvilli, osmosis and including the roles of microvilli, osmosis and active transport.active transport. Cell in the walls of the proximal Cell in the walls of the proximal

convoluted tubules convoluted tubules have microvilli facing the filtratehave microvilli facing the filtrate Increase surface area and form Increase surface area and form

pinocytic vesicles that takes pinocytic vesicles that takes droplets of solutions from the droplets of solutions from the tubuletubule

Highly concentrated in Highly concentrated in mitochondria for ATP production mitochondria for ATP production for active transport.for active transport.

Compare the composition of blood in Compare the composition of blood in the renal artery and renal vein, and the renal artery and renal vein, and compare the composition of the compare the composition of the glomerular filtrate and urineglomerular filtrate and urine

SubstanceSubstance Renal arteryRenal artery Renal veinRenal vein

OxygenOxygen HigherHigher LowerLower

Carbon dioxideCarbon dioxide Lower Lower HigherHigher

GlucoseGlucose HigherHigher lowerlower

Urea, salts waterUrea, salts water HigherHigher lowerlower

Ammonia, alcohol Ammonia, alcohol and other toxins. and other toxins. HormonesHormones

HigherHigher lowerlower

Outline the structure and action of Outline the structure and action of kidney dialysis machineskidney dialysis machines

Works on the basis of osmosis Works on the basis of osmosis and diffusionand diffusion

Made of multiple layers of thin Made of multiple layers of thin tubes made of a material that tubes made of a material that allows diffusionallows diffusion

Blood is drawn from the patient’s Blood is drawn from the patient’s blood vessel into the machine blood vessel into the machine back to the patient’s blood back to the patient’s blood vessel. vessel.

Patient’s blood contains high Patient’s blood contains high concentrations of salts and urea concentrations of salts and urea that have to be removed. that have to be removed.

Kidney dialysis machineKidney dialysis machine

Outline the structure and action of Outline the structure and action of kidney dialysis machineskidney dialysis machines The blood passes into the dialysis tubes of the The blood passes into the dialysis tubes of the

machine and as it does that, movement of ions machine and as it does that, movement of ions according to a concentration gradient takes placeaccording to a concentration gradient takes place

Dialysis fluid has no urea and it has a certain Dialysis fluid has no urea and it has a certain controlled low concentration of salts.controlled low concentration of salts.

Concentration of glucose is the same in bothConcentration of glucose is the same in both Urea moves from high to low concentration by Urea moves from high to low concentration by

diffusiondiffusion Some salts move as wellSome salts move as well A patient with kidney failure must be connected to A patient with kidney failure must be connected to

the dialysis machine in hospitals two days a week the dialysis machine in hospitals two days a week for about 12 hour each time. for about 12 hour each time.