Module 18: The Urinary System Flashcards Preview

Anatomy & Physiology > Module 18: The Urinary System > Flashcards

Flashcards in Module 18: The Urinary System Deck (17):
1

Hilum

Notch near the center of the concave border of the kidney Where the ureter leaves the kidney and where blood vessels, nerves, and lymph vessels enter and leave the kidney

2

Renal pyramids

Triangular structures that look striated (striped) due to straight renal tubules and blood vessels

3

Glomerulus

Network of capillaries
Surrounded by the Bowman’s capsule
Blood is filtered from the glomerulus and enters the Bowman’s capsule

4

Bowman's capsule

Double-walled structure that surrounds the glomerulus
Receives filtered blood (called filtrate) from the glomerulus and delivers it to the renal tubule
Contains a fluid (derived from plasma, rich in solutes, free of proteins) that is the raw material of urine

5

Renal tubule

Site of urine formation through 2 processes called reabsorption and secretion

6

Afferent arteriole

Renal artery branches into smaller blood vessels that merge as the afferent arteriole
Forms glomerulus

7

Efferent arterioles

Form peritubular capillaries

8

Basic processes of urine formation

Glomerular filtration
Tubular reabsorption
Tubular secretion

9

Glomerular filtration

Small substances are filtrated through hydrostatic pressure, no energy needed
Large molecules are NOT filtrated (e.g., blood cells and large proteins)

10

Tubular reabsorption

Occurs mostly in the proximal convoluted tubule

11

Aldosterone

Released by the adrenal glands
Helps to regulate fluid balance
Stimulates the distal tubules to reabsorb Na+ ions and
water, and to excrete K+ ions

12

Atrial natriuretic peptide

Inhibits the reabsorption of Na+ and water, decreasing blood volume and blood pressure
Relaxes glomerular mesangial cells which increases capillary surface area, increasing GFR

13

Renin

Enzyme secreted by the juxtaglomerular apparatus (located in the afferent arterioles)
Circulates in the bloodstream where it is indirectly involved with the control of blood pressure
Leads to the formation angiotensin I which is converted into angiotensin II by angiotensin-converting enzyme

14

Erythropoietin

Secreted in response to low oxygen in arterial blood
Transported in the blood stream to bone marrow

15

Micturition

Urination
The detrusor muscle of the bladder contracts as do the muscles of the pelvic floor and abdominal wall

16

Angiotensin I

Converted to angiotensin II by angiotensin-converting enzyme

17

Angiotensin II

Raises blood pressure by exerting a powerful constrictor effect on the arterioles