Urinary System

Question 1

What are the main organs of the urinary system?

Answer 1

Kidneys, ureters, urinary bladder, and urethra.

Question 2

What are the main functions of the urinary system?

Answer 2

Excretion of metabolic wastes, regulation of blood volume and pressure, electrolyte balance, and maintenance of acid-base balance.

Question 3

What hormone does the kidney secrete to regulate red blood cell production?

Answer 3

Erythropoietin.

Question 4

What hormone from the kidney regulates blood pressure?

Answer 4

Renin.

Question 5

What is the overall function of the kidneys?

Answer 5

To filter blood, remove waste, and produce urine.

Question 6

What is the functional unit of the kidney?

Answer 6

The nephron.

Question 7

What are the two main components of a nephron?

Answer 7

Renal corpuscle (glomerulus and Bowman’s capsule) and renal tubule.

Question 8

What is the function of the nephron?

Answer 8

To filter blood, reabsorb needed substances, and excrete waste as urine.

Question 9

Where are the kidneys located?

Answer 9

Retroperitoneally on either side of the vertebral column between T12 and L3.

Question 10

Which kidney is slightly lower and why?

Answer 10

The right kidney, due to the presence of the liver above it.

Question 11

What are the three main regions of the kidney?

Answer 11

Cortex, medulla, and renal pelvis.

Question 12

What is found in the renal cortex?

Answer 12

Renal corpuscles and proximal/distal convoluted tubules.

Question 13

What is found in the renal medulla?

Answer 13

Renal pyramids containing loops of Henle and collecting ducts.

Question 14

What is the renal pelvis?

Answer 14

A funnel-shaped cavity that collects urine from major calyces and channels it into the ureter.

Question 15

What are renal pyramids?

Answer 15

Cone-shaped structures in the medulla that drain urine into the calyces.

Question 16

What is the hilum of the kidney?

Answer 16

The concave medial surface where the renal artery enters and the renal vein and ureter exit.

Question 17

What vessels supply blood to and from the kidneys?

Answer 17

Renal arteries (from the aorta) and renal veins (to the inferior vena cava).

Question 18

What is the pathway of blood through the kidney?

Answer 18

Renal artery → segmental arteries → interlobar arteries → arcuate arteries → cortical radiate arteries → afferent arteriole → glomerulus → efferent arteriole → peritubular capillaries → veins → renal vein.

Question 19

Trace the pathway of urine from the kidney to the external urethra.

Answer 19

Kidney → renal pyramids → minor calyces → major calyces → renal pelvis → ureter → urinary bladder → urethra → external urethral orifice.

Question 20

What is the function of the ureters?

Answer 20

To transport urine from the kidneys to the urinary bladder by peristaltic contractions.

Question 21

What is the function of the urinary bladder?

Answer 21

To store urine until micturition (urination).

Question 22

What is the trigone of the bladder?

Answer 22

A smooth triangular region defined by the openings of the ureters and urethra; sensitive to expansion and signals urination.

Question 23

What type of muscle makes up the bladder wall?

Answer 23

Detrusor muscle (smooth muscle).

Question 24

What type of epithelium lines the bladder?

Answer 24

Transitional epithelium (urothelium), which allows stretching.

Question 25

What is the function of the urethra?

Answer 25

To conduct urine from the bladder to the external urethral orifice.

Question 26

How does the male and female urethra differ in length?

Answer 26

The male urethra is about 18–20 cm long; the female urethra is about 3–4 cm long.

Question 27

What are the three parts of the male urethra?

Answer 27

Prostatic, membranous, and spongy (penile) urethra.

Question 28

What structures does the male urethra pass through?

Answer 28

The prostate gland, urogenital diaphragm, and penis.

Question 29

What dual function does the male urethra serve?

Answer 29

It conveys both urine and semen (not simultaneously).

Question 30

What is the location of the female urethra?

Answer 30

It extends from the bladder to the external urethral orifice, anterior to the vaginal opening.

Question 31

What is the relationship of the female urethra to the vagina?

Answer 31

It runs parallel and anterior to the vaginal canal.

Question 32

Why are urinary tract infections more common in females?

Answer 32

Due to the shorter length of the female urethra and proximity to the anus.

Question 33

Where is the external urethral sphincter located?

Answer 33

In the urogenital diaphragm; composed of skeletal muscle under voluntary control.

Question 34

Where is the internal urethral sphincter located?

Answer 34

At the junction of the bladder and urethra; composed of smooth muscle under involuntary control.

Question 35

Which nerve controls voluntary urination?

Answer 35

The pudendal nerve.

Question 36

What nervous systems control micturition?

Answer 36

Parasympathetic stimulation causes bladder contraction and sphincter relaxation; sympathetic stimulation promotes storage.

Question 37

Summarize the urinary pathway from filtration to excretion.

Answer 37

Blood filtered in kidneys → urine formed in nephrons → drains into renal pelvis → ureters → bladder → urethra → external environment.

Question 38

What are the main homeostatic roles of the urinary system?

Answer 38

Regulation of blood composition, pH, volume, and pressure; excretion of wastes; hormone secretion.