L33: Urinary System

Question 1

role of kidneys

Answer 1

filter waste products from bloodstream

- convert filtrate to urine

Question 2

function of ureters?

Answer 2

transport urine from kidney to bladder via peristalsis

Question 3

function of urinary bladder?

Answer 3

storage of urine

Question 4

function of urethra?

Answer 4

transports urine from bladder to outside body

Question 5

more functions of the kidneys?

Answer 5

• Regulation of blood volume & pressure
• Regulation of erythrocyte production
  via erythropoietin
• Regulation of the blood’s inorganic ion
  balance –sodium, potassium and
  phosphate ions
• Acid-base balance through changes in
  the rates of hydrogen ion and
  ammonium secretion

Question 6

What are kidneys attached to?

Answer 6

• NOT ligaments

- held in position by their adipose capsule (soft tissue cushion)

Question 7

if adipose tissue melts, what occurs?

Answer 7

“mobile kidney”

Question 8

what is renal fascia?

Answer 8

• dense irregular tissue

- anchors kidney to surrounding tissues

Question 9

what is adipose capsule and adipose tissue?

Answer 9

capsule: fat with adipose tissue
tissue: cushioning and insulation

Question 10

what is the renal capsule?

Answer 10

• dense connective tissue
• maintains kidney shape
• protects from pathogens

Question 11

What does the renal sinus contain?

Answer 11

• minor/major calices
• renal pelvis
• renal fat
• blood vessels

Question 12

what is the access to the renal sinus?

Answer 12

renal hilum

Question 13

What is glomerulus?

Answer 13

• arterial capillary system (unique in body)

- important for blood filtration

Question 14

What is renal corpuscle?

Answer 14

• composed of a capillary network (glomerulus)

- produces a filtrate of blood

Question 15

what surrounds glomerulus?

Answer 15

• the glomerular capsule (bowman capsule)

Question 16

function of proximal convoluted tubule?

Answer 16

• reabsorbs ions, nutrients, plasma proteins, vitamins and water
• filtrate is now called tubular fluid

Question 17

function of distal convoluted tubule?

Answer 17

• secretes ions into the tubular fluid and reabsorbs water

Question 18

function of bowman’s capsule?

Answer 18

filtration

Question 19

function of loop of henle?

Answer 19

reabsorption of ions and water

Question 20

function of collecting duct?

Answer 20

for urine

Question 21

structure of ureters?

Answer 21

• 25-30cm long fibromuscular tubes
• extend from renal pelvis and exit the hilum of kidney
• paired
• retroperitoneal

Question 22

how do ureters transport urine?

Answer 22

peristaltic action of smooth muscle

Question 23

what are the 3 layers of ureters?

Answer 23

1. mucosa (innermost)
2. muscularis
3. adventina (outermost)

Question 24

function of mucosa in ureters?

Answer 24

• transitional epithelium stretchy to passage of urine

- bundles of primarily smooth muscle fibres surround mucosa/ help propel urine outside body

Question 25

function/structure of muscularis in ureters?

Answer 25

• 2 smooth muscle layers (inner longitudinal & outer circular)
• peristaltic waves propel urine

Question 26

structure/function of adventina?

Answer 26

• areolar connective tissue

- anchors ureter to posterior abdominal

Question 27

structure/function of urinary bladder?

Answer 27

• expandable muscle reservoir for urine
• retroperitoneal
• shaped like upside-down pyramid when empty
• when full; distended superiorly and oval shaped

Question 28

how does the urinary bladder receive blood

Answer 28

branches of the internal iliac arteries

Question 29

location and function of the parasympathetic axons (pelvic splanchnic nerves)

Answer 29

• come from micturition reflex center located in spinal cord S2-S4
• stimulate urination

Question 30

location/ function of the sympathetic axons

Answer 30

• T11-L2 spinal cord

- inhibit micturition

Question 31

what is micturition?

Answer 31

urination

Question 32

True or False:

The urethra is sexually dimorphic

Answer 32

true

Question 33

what is the prostatic urethra in the male urethra?

Answer 33

• 3cm long

- extends through prostate gland where multiple small prostatic ducts enter

Question 34

what is the membranous urethra in the male urethra?

Answer 34

• shortest portion (<1cm)

- from inferior prostate gland through urogenital diaphragm

Question 35

what is the spongy urethra in the male urethra?

Answer 35

• 15cm in erectile tissue in penis (corpus spongiosum)

- extends to external urethral orifice

Question 36

in the male urethra, role of internal urethral sphincter?

Answer 36

prevents simultaneous passage of sperm and urine

Question 37

role of female urethra?

Answer 37

• 3-5cm long

- only transmits urine from bladder to vestibule (external space immediately internal to labia minora)