Module 25- GU Anatomy

Question 1

What are the two main functions of the urinary system?

Answer 1

• keep track of electrolytes, water content, and acids of the blood
• removes metabolic wastes, drug metabolites, and excess fluids

Question 2

What is part of the urinary system?

Answer 2

• kidneys
• filter 200 L of blood each day

Question 3

What is a renal disorder?

Answer 3

• kidney disease

Question 4

On an average how many Canadians are told their kidneys have failed?

Answer 4

• an avg of 15
• Each year there is a 7% increase in the number of people diagnosed with kidney disease
• 43,200 are being treated for kidney failure

Question 5

What does kidney disease also contribute to?

Answer 5

• risk of cardiovascular disease
• hypertension
• other chronic diseases

Question 6

What do our kidneys do?

Answer 6

• filter blood and produce urine
• bean-shaped
• found in the retroperitoneal space
• Aid electrolyte balance

Question 7

What is the hilum of the kidneys?

Answer 7

• Cleft formed on the medial side of the kidney
• Where ureters, renal blood vessels, lymphatic vessels and nerves enter and leave kidney

Question 8

What does the urinary bladder do?

Answer 8

• stores urine until is released

Question 9

What do ureters do?

Answer 9

• transport urine from the kidneys to the bladder

Question 10

What does the urethra do?

Answer 10

• transports urine from the bladder out of the body

Question 11

What is the renal fascia? What does the renal fascia do?

Answer 11

• layer of dense fibrous connective tissue
• anchors the kidney to the abdominal wall

Question 12

What is the internal anatomy of the kidney?

Answer 12

• Cortex
• Medulla
• Renal pelvis

Question 13

Cortex

Answer 13

Light colored, outer region closest to the capsule

Question 14

Medulla

Answer 14

• Middle layer
• Includes the cone-shaped renal pyramids, and renal columns

Question 15

Renal pyramids

Answer 15

• Flat, funnel shaped tube that fills the sinus at the level of the hilum

Question 16

What is the calyces?

Answer 16

• Branch off the pelvis and connect with the renal pyramids to receive urine draining from the collecting tubules

Question 17

Approximately how much of the body’s systemic cardiac output of blood flows through the kidneys each min?

Answer 17

-approx one-fourth

Question 18

How does blood flow from the abdominal aorta into the kidney?

Answer 18

• By the way of the renal artery

Branches into the:
- Afferent arteriole, then into
- Glomerulus- (main filter for the blood) then enters
- Efferent arteriole, branches into
- Peritubular capillaries (tubular reabsorption occurs)

Question 19

What is unique to the kidney?

Answer 19

• The secondary set of capillaries is unique to the kidney
• No other organ in the body has two distinct capillary beds
• The capillaries merge to form venules and veins
• Until the rebel vein leaves the hilum
• Carrying cleansed blood to the inferior vena cava

Question 20

Where are nephrons found?

Answer 20

• In the cortex

Question 21

What are the nephrons?

Answer 21

• Structural and functional units of the kidney

Question 22

What are nephrons composed of?

Answer 22

• Glomerulus
• Glomerular capsule
• Proximal convoluted tubule (PCT)
• Loop of Henle
• Distal convoluted tubule (DCT)

Each kidney contains approximately 1.25 million nephrons

Question 23

What is the glomerular capsule?

Answer 23

• Double-layered cup
  
  • Podocytes
  • Glomerular filtration rate (GFR)

Question 24

What are podocytes?

Answer 24

• Wrap around the capillaries forming filtration slits
• Filtrate passes through, and into the capsule
• Inhibits large proteins from entering

Question 25

What is the Glomerular filtration rate (GFR)?

Answer 25

- Amount of filtrate produced - Maintained at a relatively constant rate of 125 ml/hr - Changes in the GFR cause many of the renal emergencies

Question 26

What occurs at the Loop of Henle?

Answer 26

This where additional resorption of water and electrolytes occur

Question 27

What are the 2 sections of the Loop of Henle?

Answer 27

- Descending limb (permeable to water but impermeable to sodium and chloride) Ascending limb (impermeable to water but permeable to sodium and chloride)

Question 28

What is the Juxtaglomerular apparatus?

Answer 28

- Site where the efferent arteriole comes in contact with the DCT - Sensitive to pressure changes - Release renin with changes in blood pressure

Question 29

What two hormones control the final adjustment to the composition of urine?

Answer 29

- Antidiuretic (ADH): produced by hypothalamus, stored in pituitary - Aldosterone- produced by adrenal glands

Question 30

When is ADH released?

Answer 30

- When solute concentration of blood increases due to sweating or decreased fluid intake - Increases permeability to water - Water leaves DCT and collecting ducts and re enters the bloodstream

Question 31

What does aldosterone do?

Answer 31

- increases the rate of active resorption sodium and chloride into the blood

Question 32

What are diuretics?

Answer 32

Chemical that increase urinary output, work in a variety of ways - A substance that is not reabsorbed from the filtrate will increase the amount of water retained in the urine - alcohol encourages diuresis by inhibiting the production of ADH - Caffeine and common diuretic medications such as Lasix inhibit the sodium importers in the DCT and collecting ducts

Question 33

Where is the bladder?

Answer 33

Most of the bladder sits anterior abdominal cavity - Dome of the bladder sits posterior or retroperitoneum

Question 34

What does the bladder do when empty?

Answer 34

- The bladder collapses and the muscular walls fold over onto themselves - When urine accumulated the bladder becomes pear shaped - Stretching of the bladder produces the micturition reflex

Question 35

What is micturition reflex?

Answer 35

- Stretching of the bladder wall stimulates nerve impulses - Spinal reflex that causes contraction of the bladder’s smooth muscles, which in turn produces the urge to void as pressure is exerted

Question 36

What is the female urethra?

Answer 36

- Exits at the site of the external genitalia - 4 cm long on average

Question 37

What is the male urethra?

Answer 37

- 20 cm long Divided into three regions: - Prostatic- from bladder to prostate - Membranous- prostate to penis - Penile- through penis to external urethral opening