2. RENAL FUNCTION

1 to 1.5 million

kidney contains approximately _______________ functional units called NEPHRONS

vein ; artery

Renal _________ ; to kidney

Renal _________ ; to heart

• renal blood flow,

• glomerular filtration,

• tubular reabsorption,

• tubular secretion.

ENUMERATE

the fn’s of kidney

25%

The human kidneys receive approximately ____ of the blood pumped through the heart at all times.

85%

cortical nephrons make up approximately ____ of nephrons

efferent arteriole

what arteriole is smaller?

to create hydrostatic pressure differential

why is efferent arteriole smaller?

peritubular capillaries

capillaries surrounding the PCT and DCT

vasa recta

capillaries surrounding the loop of Henle

afferent : dilate

efferent : vasoconstrict

if ↓ bld pressure

afferent : ___________

efferent : ___________

afferent : vasoconstrict

efferent : dilate

if ↑ bld pressure

afferent : ___________

efferent : ___________

1.73 m2

what is the average body size

1200 mL/min

total renal blood flow of an average body size

600 to 700 mL/min

what is the total renal plasma flow?

renal artery → afferent arteriole → glomerulus → efferent arteriole → peritubular capillaries / PCT → vasa recta / loop of Henle → peritubular capillaries / DCT → renal vein

ENUMARATE

the order of the flow of blood in renal blood flow

1. capillary wall membrane

2. basement membrane (basal lamina)

3. visceral epithelium (podocytes) of Bowman’s capsule

ENUMERATE

three cellular layer of the glomerulus

70,000

glomerulus serves a a non-selective filter that allow the passage of substances with molecular weights of less than ________

• LOW bld pressure

• LOW sodium content

ENUMERATE

certain conditions wherein RAAS controls the regulation of blood flow

• Juxtaglomerular (JG) cells

• macula densa

what are the 2 parts of the juxtamedullary apparatus?

juxtamedullary apparatus

changes in bld psi and plasma Na+ content is monitored by?

glomerulus

consists of a coil of approximately eight capillary lobes referred to collectively as the capillary tuft.

Renin

is an enzyme produced by the juxtaglomerular cells, is secreted and reacts with the blood-borne substrate angiotensinogen to produce the inert hormone angiotensin I.

angiotensin I

renin + angiotensinogen = ?

angiotensinogen

a proenzyme that is produced by the liver in a constant manner that reacts with renin

angiotensin converting enzyme (ACE)

what enzyme converts angiotensin I to angiotensin II. this enzyme is present in the lungs

angiotensin II

angiotensin I + ACE =

• vasoconstriction/vasodilation of arterioles

• reabsorption of Na+ in PCT

• release of aldosterone in renal gland (Na+ reabsorption in DCT)

• release of ADH in reax in CD

ENUMERATE

4 outcomes of angiotensin II

1.010

SG of the ultrafiltrate

hydrostatic pressure

the psi within the blood vessels that pushes the blood to glomerulus

120 mL

The body cannot lose _____ of water-containing essential substances every minute.

• glucose,

• amino acids,

• salts

ENUMERATE

actively reabsorbed substances in PCT

• chloride

ENUMERATE

actively reabsorbed substances in ascending loop of Henle

• sodium

ENUMERATE

actively reabsorbed substances in DCT

• water

ENUMERATE

passively reabsorbed substances in PCT, DLOH, CD

• urea

ENUMERATE

passively reabsorbed substances in PCT, ALOH

• Sodium

ENUMERATE

passively reabsorbed substances in ALOH

passive transport

it is the movement of substances that is controlled by concentration gradients.

ascending loop of Henle

Passive reabsorption of water takes place in all parts of the nephron except the _____________________

160 to 180 mg/dL

renal threshold for glucose

tubular damage

glucose appearing in the urine of a person with a normal blood glucose level is the result of what dse?

countercurrent mechanism

what mechanism maintains the concentration (osmotic gradient) of the medulla

aldosterone

what hormone regulates the reabsorption response to the body’s need for Na+

• Na+ (passive)

• Cl- (active)

what are the substances that are reabsorbed by ascending loops of Henle

↓ ; ↑

↑ Body Hydration = ___ADH ___Urine Volume

↑ ; ↓

↓ Body Hydration = ___ADH ___Urine Volume

tubular secretion

a process wherein the kidney secretes waste products that cannot be filtered by glomerulus. thus it maintains the acid-base balance of the body

reabsorption

____________ = filtrate to blood

secretion

____________ = blood to filtrate