Renal (Urinary) System

Question 1

Where are the kidneys and ureters?

Answer 1

They lie retroperitoneal in the abdominal cavity; partly covered by ribs. Kidneys lie on the posterior wall

Question 2

Where is the urinary bladder?

Answer 2

In the pelvic cavity

Question 3

Where is the urethra?

Answer 3

Below the pelvis

Question 4

What are the renal arteries?

Answer 4

Branch from the aorta

Question 5

What are the renal veins?

Answer 5

Join the inferior vena cava

Question 6

What are the 3 layers of the ureter?

Answer 6

• Transitional epithelium & goblet cells
• Smooth muscle
• Areolar connective tissue

Question 7

What does peristalsis do?

Answer 7

Moves urine from the renal pelvis to the urinary bladder

Question 8

Explain the urethra in women?

Answer 8

It travels a slightly curved course as it passes interiorly through the pelvic floor into the perineum, where it passes through the deep perineal pouch and perineal membrane before opening in the vestibule that lies between the labia minora

Question 9

Explain the urethra in men?

Answer 9

Beginning at the base of the bladder and passing inferiorly through the prostate, it passes through the deep perineal pouch and perineal membrane and immediately enters the root of the penis.

Question 10

What is the urethra?

Answer 10

The exit tube for urine from the bladder to the outside world

Question 11

What 2 muscular sphincters control the flow of urine?

Answer 11

• Internal urethral sphincter

- External urethral sphincter

Question 12

What is the indentation on the kidneys medial border called?

Answer 12

Renal hilum

Question 13

What surrounds the kidneys?

Answer 13

Perinephric fat surrounds and cushions the kidney. This also anchors the kidney to the posterior abdominal wall

Question 14

What are the 2 regions of the kidney?

Answer 14

The outer light red renal cortex and the inner darker red/brown renal medulla

Question 15

How many pyramids in the kidneys medulla?

Answer 15

8 - 18 pyramids separated by columns or cortical tissue

Question 16

What 2 zones are the kidneys divided into functionally?

Answer 16

The functional area and the drainage area

Question 17

What does the functional area of the kidney consist of?

Answer 17

Renal cortex and renal medulla

Question 18

What happens in the drainage area of the kidney?

Answer 18

Apex of a pyramid is known as the renal papilla where thousands of papillary ducts drain urine into cup like minor calyces

Question 19

What are minor calyces?

Answer 19

Drain into 2 - 3 major calyces

Question 20

What are major calyces?

Answer 20

Drain into the renal pelvis which connects to the ureter

Question 21

What are nephrons in kidneys?

Answer 21

They are the functional unit of the kidney. They consist of a renal tubule and associated blood vessels

Question 22

What are cortical nephrons?

Answer 22

They have short loops of Henle that mostly stay in the cortex

Question 23

What are juxtamedullary nephrons?

Answer 23

They have long lops of Henle

Question 24

What is the structure of a nephron?

Answer 24

Renal corpuscle
- Glomerulus 
- Glomerular (Bowmans) capsule 
Renal Tubule 
- Proximal convoluted tubule 
- Loop of Henle 
- Distal convoluted tubule

Question 25

What 3 stages does urine production occur?

Answer 25

- Glomerular filtration - Tubular reabsorption - Tubular secretion

Question 26

What is glomerular filtration?

Answer 26

Takes place in the glomerulus. Blood pressure in afferent arterioles forces water and most solutes in the plasma through wall of glomerulus capillaries and into the glomerular capsule which empties into the renal tubule

Question 27

What is glomerular filtration rate (GFR)?

Answer 27

GFR is the amount of filtrate formed by both kidneys each minute - males 125ml/min - females 105ml/min GFR is directly related to blood pressure

Question 28

Which hormones can affect GFR?

Answer 28

- Atrial Natriuretic Peptide (ANP) - Angiotensin - Hypovolaemia

Question 29

What is ANP?

Answer 29

This hormone produced by the atria of the heart when the pressure inside them exceeds normal. This means that there is more fluid circulating than healthy.

Question 30

What is the response of ANP?

Answer 30

To squeeze more blood filtrate through the glomerulus (by making the glomerular exit vessel small) so excess fluid will go to the bladder and out the body thus reducing bp

Question 31

What is angiotensin?

Answer 31

This hormone is released during haemorrhage states, will result in too little fluid circulation

Question 32

What is hypovolaemia?

Answer 32

First angiotensin lowers the GFR initially, it reduces kidney circulation to conserve circulation to other organs (like the brain). This reduces GFR temporarily. Angiotensin's action later restores GFR because it influences another hormone called aldosterone this rescues water as it leaves the kidney, this reabsorption restores circulating blood volume levels

Question 33

What is tubular reabsorption/vasa recta?

Answer 33

As filtered fluids move along renal tubule to collecting ducts most water and useful solutes are reabsorbed by tubular cells and returned to peritubular capillaries. 99% of glomerular filtrate is reabsorbed by tubules. Occurs mostly in PCT

Question 34

What is tubular secretion?

Answer 34

This is the process by which substances move into the distal and collecting tubules from blood in the peritubular capillaries mainly by active transport.

Question 35

What is tubular secretion important for?

Answer 35

- disposing of substances not already in the filtrate - maximising removal of waste e.g. urea - excretion of some drugs - removal of excess ions - secreting H+ to restore blood pH

Question 36

What is antidiuretic hormone (ADH)?

Answer 36

Produced by the posterior pituitary in response to plasma concentration. it regulates bodies fluid balance by the concentration or dilution of urine - Bp low or dehydration = high ADH - Excess intake of fluid = low ADH

Question 37

What is micturition?

Answer 37

Reflex action in infants and small children. Older children and adults learn to control micturition by controlling the external urethral sphincter and pelvic floor muscles. Eventually bladder filling will override these voluntary controls

Question 38

What should be found in normal urine?

Answer 38

- water - urea - uric acid - creatine - excess inorganic salts

Question 39

What might be found in abnormal urine?

Answer 39

- albumin - glucose - red blood cells - white blood cells - kettle bodies - bilirubin - urobiligen - bacteria