Control of blood water potential-structure of the nephron

Question 1

What is the structure of the mammalian kidney?

Answer 1

-in mammals there are two kidneys found at the back of the abdominal cavity, one each side of the spinal cord

Question 2

What is a kidney made up of?

Answer 2

• the fibrous capsule
• the cortex
• the medulla
• the renal pelvis
• the ureter
• the renal artery
• the renal vein

Question 3

What is a fibrous capsule?

Answer 3

-an outer membrane that protects the kidney

Question 4

What is a cortex?

Answer 4

-a lighter coloured outer region made up of renal (bowman’s) capsules, convoluted tubules and blood vessels

Question 5

What is a medulla?

Answer 5

-a darker coloured inner region made up of loops or Henle, collecting ducts and blood vessels

Question 6

What is a renal pelvis?

Answer 6

-a funnel shaped cavity that collects urine into the ureter

Question 7

What is a ureter?

Answer 7

-a tube that carries urine into the bladder

Question 8

What is a renal artery?

Answer 8

-supplies the kidney with blood from the heart via the aorta

Question 9

What is a renal vein?

Answer 9

-returned blood to the heart via the vena cave

Question 10

What are nephrons?

Answer 10

• tubular structures
• narrow
• closed at one end
• two twisted regions separated by a long hairpin loop

Question 11

What is each nephron made up of?

Answer 11

• bowman’s capsule
• proximal tubule
• loop of Henle
• distal tubule
• collecting duct

Question 12

What is renal bowman’s capsule?

Answer 12

• surrounds the glomerulus

- layer of podocytes

Question 13

What is proximal convoluted tubule?

Answer 13

• a series of loops surrounded by blood capillaries

- its walls are made of epithelial cells which have microvilli

Question 14

What is a loop of Henley?

Answer 14

• a long hairpin loop that extends from the cortex into the medulla of the kidney and back again
• it is surrounded b blood capillaries

Question 15

What is distal convoluted tubule?

Answer 15

• a series of loops surrounded by blood capillaries

- its walls are made of epithelial cells, but it s surrounded by fewer capillaries than the proximal tubule

Question 16

What is the collecting duct?

Answer 16

• a tube into which a number of distal convoluted tumbles from a number of nephrons empty
• it is lined by epithelial cells and becomes increasingly wide as it emptied into the pelvis of the kidney

Question 17

Which blood vessels are associated with each nephron?

Answer 17

• affront arterial
• glomerulus
• efferent arterial
• blood capillaries

Question 18

What is affront arterial?

Answer 18

• a tiny vessel that ultimately arises from the renal artery and supplies the nephron with blood
• the afferent arteriole enters the renal capsule of the nephron where it forms the glomerulus

Question 19

What is glomerulus?

Answer 19

• a many branched knot of capillaries from which fluid is forced out of the blood
• the glomerular capillaries recombine to form the efferent arterial
• in mammals the glomerulus is the only capillary bed in which an arterials (the afferent arterial) supplies it with blood and an arterial (the efferent arterial) also drains blood away
• in all other mammalian capillary beds it is a venule that drains away the blood

Question 20

What is efferent arteriole?

Answer 20

• a tiny vessel that leaves the renal capsule
• it has a smaller diameter than the affront arterial and so causes an increase in blood pressure within the glomerulus
• carries blood away from the renal capsule and later branches to form the blood capillaries

Question 21

What are blood capillaries?

Answer 21

-a network of capillaries that surrounds the proximal convoluted tubule, the loop of Henle and the distal convoluted tubule and from where they reabsorb mineral salts, glucose and water