Renal/urinary System

Front 1

Functions of the kidney

Back 1

1. Filters blood - 200 litres daily, allowing toxins, metabolic wastes and excess ions to be excreted in urine.

2. Regulate volume and concentration of blood

3. Maintain homeostasis (proper balance between water, salts, acids and bases.

4. Produce renin to help regulate blood pressure.

5. Produce erythropoietin to stimulate red blood cell production.

6. Activate vitamin D and produce glucose during prolonged fasting

Hint 1

6

Front 2

How much of filtrate is recovered back into the body?

Back 2

198 litres

(99%)

1% becomes urine

Front 3

Where are kidneys found?

Back 3

- kidneyslie in a retroperitoneal position in the superior lumbar region and extend fromthe twelfth thoracic to the third lumbar vertebrae

- Protected by last rib

- Right kidney lower than left.

Front 4

Hilus

Back 4

= Part of kidney where Ureters,renal blood vessels, lymphatics, and nerves enter and exit.

Front 5

Urinary bladder

Back 5

= Temporary storage reservoir for urine.

Front 6

Paired ureters

Back 6

= Transport urine from kidneys to bladder

Front 7

Urethra

Back 7

= Transports urine from the bladder out of the body.

- Different length in males/females (F=shorter, more prone to infection)

- Sphincters internal and external. External = voluntary.

Front 8

Renal artery

Back 8

= Transports blood to the kidney to be filtered

Front 9

Renal vein

Back 9

= Transports blood away from the kidney after it has been filtered.

Front 10

Renal membranes

Back 10

1. Inner = renal capsule. Shiny, impermeable so prevents infections spreading to the kidney.

2. Middle = adipose capsule, white fat, cushions kidney.

3. Outer = Renal fascia. Dense fibrous tissue that anchors kidney.

Hint 10

3

Front 11

Fluid in nephron before collecting duct

Back 11

= filtrate

Front 12

Fluid in nephron after collecting duct

Back 12

= urine

Front 13

1

Back 13

= Renal pyramid

- Made of parallel bundles of urine collecting tubules

- Found in medulla.

Front 14

2

Back 14

= Cortex

- Outer region.

- Light coloured, granular.

Front 15

3

Back 15

= Renal column

- Inward extensions of cortical tissue that separate the renal pyramids.

Front 16

4

Back 16

= Renal sinus

Front 17

5

Back 17

= Major calyx

- Large branches of the renal pelvis (funnel like) that collect urine draining from collecting ducts and empty urine into the pelvis

Front 18

6

Back 18

= Minor calyx

- Smaller branches of renal pelvis that collect urine draining from collecting ducts.

Front 19

7

Back 19

= Renal pelvis

- Flat funnel shaped tube that major calyxes drain into before leaving kidney into ureters.

Front 20

8

Back 20

= Renal capsule

- Inner renal membrane

Front 21

9

Back 21

= Ureter

- Transports urine from kidney to bladder

Front 22

How many nephrons does each kidney contain?

Back 22

1 million

Front 23

nephron

1

Back 23

=Renal corpuscle

- Glomerus and Bowman's capsule that encloses it.

Front 24

nephron

2

Back 24

= Bowman's capsule

- Blind,cup-shaped end of a renal tubule that completely surrounds the glomerulus

- Collects filtrate

Front 25

nephron

3

Back 25

= Glomerulus

- atuft of capillaries associated with a renal tubule

- supplied by afferent arteriole

- flows into efferent arteriole

- Filtration occurs here.

- Blood cells and plasma proteins stay in blood

- water and other small molecules enter bowman's capsule as filtrate.

Front 26

nephron

4

Back 26

= Proximal convoluted tubule.

- Reabsorbs 65% of water from filtrate

- Reabsorbs Na+, K+, Cl-, Mg2+, Ca2+, HCO3-

- Reabsorbs glucose, amino acids, vitamins

- Secretes substances into tubule.

- Cuboidal cells with microvilli and mitochondria.

Front 27

nephron

5

Back 27

= Afferent arteriole

- Supplies glomerulus with blood for filtering.

- Wider than efferent arteriole so pressure generated.

Front 28

nephron

6

Back 28

= Distal convoluted tubule

- 19% water reabsorbed under hormonal control

- Functions more in secretion than reabsorption.

Front 29

nephron

7

Back 29

= Interlobar artery

Front 30

nephron

8

Back 30

= Efferent arteriole

- Carries blood away from glomerulus

- Becomes peritubular capillaries that wrap around tubules

- Narrower than afferent artery.

Front 31

nephron

10

Back 31

= Loop of Henle Descending limb

- Reabsorption of 15% water.

- Similar to proximal convoluted tubule.

- Followed by thin segment that regulates electrolytes

Front 32

nephron

11

Back 32

= Collecting duct.

- Collects filtrate from distal convoluted tubules and carries to calyces.

- Urine after it enters.

Front 33

nephron

12

Back 33

= Ascending limb of loop of Henle

- Actively pumps sodium out of the tubule to surrounding interstitial fluid.

- Impermeable to water.

Front 34

nephron

13

Back 34

= Loop of Henle

- Descending and ascending limb

- Function = reabsorption.

Front 35

Renal tubule

Back 35

- Distal convoluted tubule nearer the collecting ducts.

- Function in maintaining the acid-base balances of body.

- Helps maintain the body's water and salt balance.

- Excretion of drugs and toxic waste.

Front 36

2 cell types of renal tube

Back 36

1. IntercalatedcellsCuboidalcells with microvilli Functionin maintaining the acid-base balance of the body

2. PrincipalcellsCuboidalcells without microvilliHelpmaintain the body’s water and salt balance (aldosterone)

Front 37

Juxtaglomerula apparatus

Back 37

-Juxtaglomerularcells (Afferent arteriole)

- MaculaDensaCells (Distal convoluted tubule)

- Secretes enzyme renin.

- Plays important role in regulation of filtrate formation and blood pressure.

Front 38

Types of nephron

Back 38

- Cortical located in cortex = 85%

- Juxtamedullary = Arelocated at the cortex-medulla junction

- Haveloops of Henle that deeply invadethe medulla

- Haveextensive thin segments - Areinvolved in the production of concentrated urine

Front 39

Reabsorption and secretion

Proximal convoluted tubule

Back 39

-Na+ andother substances removed

- Waterfollows passively

- Filtratevolume reduced

Front 40

Reabsorption and secretion

Descending limb loop of Henle

Back 40

- Waterexits passively, solute enters

- Filtratevolume reduced 15%

Front 41

Reabsorption and secretion

Ascending limb of loop of Henle

Back 41

- Na+,Cl-, K+transported out of filtrate

- Waterremains

Front 42

Reabsorption and secretion

Distal convoluted tubules

Back 42

- Water movement out regulated by ADH

- If absent, water not reabsorbed and dilute urine produced

- If ADH present, water moves out, concentrated urine produced

Front 43

Parathyroid hormone

Back 43

- Secreted by parathyroid gland

- Increases reabsorption of calcium in the distal collecting tubules = increases blood calcium level

Front 44

Calcitonin

Back 44

- Secreted by the thyroid gland

- Decreases reabsorption of calcium in distal collecting tubules = decreases blood calcium level.

Front 45

Antidiuretic hormone (ADH)

Back 45

- Produced by posterior pituitary.

- Production stimulated by: increased osmolality (more concentrated) blood, decreased blood pressure (detected by the hypothalamus)

- Causes increased water permeability in distal convoluted tubule and collecting duct.

= Decrease urine volume, increase blood volume and pressure

Hint 45

Where produced?

What stimulates production?

What effect does it have?

Front 46

Atrial natriuretic hormone (ANH)

Back 46

- Produced by cardiac muscle cells.

- Production stimulated when stretch receptors in atria of heart are stimulated = stimulated by high blood pressure.

- Reduces reabsorption of sodium and water by proximal convoluted tubule and collecting ducts.

- Reduces ability of kidney to concentrate urine (more water +sodium lost)

= Lowers blood volume

- Inhibits ADH production

Hint 46

Where produced?

What stimulates production?

What effect does it have?

Front 47

Aldosterone

Back 47

- Produced by adrenal cortex.

- Production stimulated by: high blood potassium, angiontensin II (renin).

- Regulates excretion of sodium = increases reabsorption of water +sodium.

- Increased excretion of potassium.

Front 48

Renin

Back 48

- Produced by juxtaglomerular cells in kidney.

- Production stimulated by low blood volume, low blood pressure.

- Converts plasma protein angiotensinogen (produced by liver) into angiotensin I.

- Angiotensin converting enzyme (ACE) in lungs converts it to angiotensin II.

= a vasoconstrictor so increased blood pressure.

- Also stimulates release of aldosterone.