The Urinary System

Question 1

Kidneys

Answer 1

• located under the muscles of the back and just above the waistline.
• right kidney is usually a little lower than the left

Question 2

Primary Functions of Kidneys (4)

Answer 2

1. The excretion of toxins and nitrogenous wastes
2. Regulation of blood levels of many chemicals
3. Maintenance of water balance
4. Regulation of blood pressure
   - these functions necessitates that a great deal of blood volume passes through the kidneys

Question 3

Formation of Urine

Answer 3

• end product of kidneys is urine, as it allows wastes and excess electrolytes and such to exit the body

Question 4

Nephron

Answer 4

• the tiny functional units of the kidneys

Question 5

Filtration

Answer 5

• continual process in the renal corpuscles, with a typical filtration rate of ~125 ml per minute
• most isn’t filtered out so we have more processes

Question 6

Reabsorption

Answer 6

• movement of substances out of the renal tubules back into the blood.
• allows for the preservation of the “good stuff”
• What’s reabsorbed accounts for about 99% of what was filtered out in the first place

Question 7

Secretion

Answer 7

• waste substances, including things like toxins, nitrogenous wastes, excess ions and metabolized by-products of pharmaceuticals, enter urine

Question 8

Uerters

Answer 8

• long, narrow tubes with smooth muscle lined with a mucous membrane layer.
• have expanded upper end located inside the kidney to drain urine from the renal pelvis to the urinary bladder
• ureters connect the kidneys to the urinary bladder

Question 9

Urinary Bladder

Answer 9

• elastic, mucous membrane-lined, muscular organ, capable of great expansion.
• stores urine and, when “full,” stretches to the point where it sends nerve messages to the brain

Question 10

Urethra

Answer 10

• mucous membrane-lined tube that goes from the urinary bladder to the outside world is called the urethra
• passage of urine from the bladder to the exterior of the body
• females = only for urine
• males = for semen and urine

Question 11

Internal urethral sphincter

Answer 11

• under involuntary control

Question 12

External urethral sphincter

Answer 12

• under voluntary control

Question 13

Micturition

Answer 13

• when you have to urinate
• is initiated by the emptying reflex
• also called voiding or urination

Question 14

Enuresis / Incontinence

Answer 14

• E = involves involuntary urination by a child, often in the form of bedwetting
• I = involuntary voiding in adults

Question 15

Urinary Retention

Answer 15

• urine is produced normally, but is not voided (keeping urine)

Question 16

Urinary Suppression

Answer 16

• urinary bladder is normal, but no urine is produced

Question 17

Urinary Tract Infections (UTIs)

Answer 17

• far more common in women
• much shorter urethra than men so bacteria can be introduced during sex, which highlights the importance of the “post-coital pee,” as it helps to expel bacteria

Question 18

Obstructive Disorders

Answer 18

• block the flow of urine

- kidney stones

Question 19

Renal Calculi + Renal Colic

Answer 19

• name for kidney stones
• Renal Colic is pain caused by kidney stones
• may cause blood in the urine (hematuria), as can both kidney and bladder cancer

Question 20

Acute Renal Failure

Answer 20

• kidneys stop working abruptly; it’s usually reversible.

Question 21

Chronic Renal Failure

Answer 21

• Loss of kidney function due to loss of functional nephrons; potentially fatal

Question 22

Dysuria

Answer 22

• burning urination

Question 23

Cystistis

Answer 23

• inflammation of the bladder

- more common in females