Kidney structure and function

Question 1

Kidneys

Answer 1

• Fliters waste out of blood

- Waste that is collected combines with water = urine

Question 2

Osmoregulation

Answer 2

Homeostatic control of the water potential of the blood

Question 3

Water potential

Answer 3

• Tendency of water molecules to move from one place to another

Question 4

Solution

Answer 4

• Must have a negative water potential

Question 5

Solute

Answer 5

• Added to pure water - water potential becomes more negative

Question 6

Solution

Answer 6

• Cannot have a positive number

Question 7

What is a kidney made up of?

Answer 7

• Fibrous capsule
• Cortex
• Medulla
• Renal Pelvis
• Ureter
• Renal artery
• Renal vein

Question 8

Fibrous capsule

Answer 8

• Protective outer coating of the kidney

Question 9

Cortex

Answer 9

• Light coloured outer area that is made up of renal capsule, convoluted tubes and blood vessels

Question 10

Medulla

Answer 10

• Darker coloured inner area that is made up of loops Henle, collecting ducts and blood vessels

Question 11

Renal Pelvis

Answer 11

• Funnel- shaped space where urine is collected, which then flows into the ureter

Question 12

Ureter

Answer 12

• The tube that carries urine to the bladder

Question 13

Renal artery

Answer 13

• Transports oxygenated blood from the heart from a branch of the aorta

Question 14

Renal vein

Answer 14

• Carries deoxygenated and filtered blood towards the vena cava as it moves back to the heart

Question 15

Kidney Nephron

Answer 15

• Narrow tube - 14mm in length
• Closed at one end - renal capusle end
• Twisted regions - convoluted tubules - separated by a long hairpin loop (loop of Henle)

Question 16

What is a nephron made of?

Answer 16

• Renal (Bowman’s) capsule
• Proximal convoluted tubles (PCT)
• Loop of Henle
• Distal convoluted tubule (DCT)
• Collecting duct

Question 17

Renal (Bowman’s) capsule

Answer 17

• Cup shaped structure
• Surrounded by a mass of blood capillaries (GLOMERULUS)
• Podocytes - Inner layer of the capsule is made up of specialised cells

Question 18

Proximal convoluted tubles

Answer 18

• Twisted tubule with walls made up of epithelial cells ith microvilli
• Surrounded by blood capillaries

Question 19

Loop of Henle

Answer 19

• Section of he tubule that forms a long loop
• Surrounded by blood capillaries
• Extends from the kidney cortex to the medulla and then back up

Question 20

Distal convoluted tubule

Answer 20

• Twisted tubule with walls made up of epithelial cells
• Surrounded by fewer blood capillaries
• Connects the loop of Henle with the collecting duct

Question 21

Collecting duct

Answer 21

• Straight section of tubule - wider at the end than the beginning
• Lined with epithelial cells
• Tubules from a number of neuphrons lead into it (DCT)

Question 22

Afferent Arteriole

Answer 22

• Tiny blood vessel which branches from the renal artery
• Supplies the nephron with blood
• Enters the renal capsule = glomerulus

Question 23

Glomerulus

Answer 23

• Knot of capillaries that have many branches

- Fluid is forced out of the blood by Ultrafiltration

Question 24

Ultrafiltration

Answer 24

• Under very high pressure caused by the very small diameter of the efferent arteriole

Question 25

Efferent arteriole

Answer 25

• Blood leaves the glomerulus and moves into the efferent arteriole
• Carries blood away from the renal capsule

Question 26

Blood capillaries

Answer 26

• Surround the PCT, loop of Henle and the DCT
• Enable mineral salts, glucose and water to be reabsorbed according to what is needed by the body - SELECTIVE REABSORBANCE

Question 27

Venules

Answer 27

• Blood capillaries merged together - renal vein

- Blood becomes deoxygenated as it moves through these blood vessels

Question 28

Processes

Answer 28

Bowman’s capsule - Ultrafiltration
Proximal tubule - Selective reabsorption
Loop of Henle - Osmoregulation (salt gradient)
Distal Tubule - Selective absorption
Collecting duct - Osomoregulation (water retention)