MMSC402 exam 1

Where does plasma filtration occur in the kidney?

Collecting duct

Cortex

Medulla

Loop of Henle

Cortex

What happens within each glomeruli when the blood pressure is low?

The afferent becomes smaller and the efferent becomes larger.

Both the afferent and the efferent become smaller.

The afferent becomes larger and the efferent becomes smaller.

Both the afferent and the efferent become larger.

The afferent becomes larger and the efferent becomes smaller

What happens when the hypothalamus releases vasopressin?

Water is reabsorbed.

Water is secreted.

Sodium is secreted.

Sodium is reabsorbed.

Water is reabsorbed

Where does aldosterone controlled sodium reabsorption occur?

Descending Loop of Henle

Ascending Loop of Henle

Distal Convoluted Tubules

Proximal Convoluted Tubules

Distal Convoluted Tubules

In what part of the nephron is glucose passively reabsorbed?

The ascending limb of the Loop of Henle.

Glucose is not passively reabsorbed.

The Bowman's capsule.

The proximal convoluted tubule.

Glucose is not passively reabsorbed

Urea is an organic solute in the urine. It is made from:

Glucose + carbohydrate breakdown

Urobilinogen breakdown

Cortisol breakdown

Protein + amino acid breakdown

protein + amino acid breakdown

What is the correct term for the complete cessation of urine flow?

Nonuria

Antiuria

Anuria

Oliguria

Anuria

Why must the temperature of a urine be taken during the collection of a specimen for drug testing?

The urine must be at body temperature to assure it is a fresh collection.

The urine must be at body temperature for the test to work.

The specimen must be at room temperature to assure it is a fresh collection.

The urine must be at room temperature for the test to work.

The urine must be at body temperature to assure it is a fresh collection

Why are creatinine clearance values lower in women than in men?

Women have smaller kidneys.

Creatinine clearance is decreased by estrogen.

Women have less muscle mass.

Women have more body fat.

Women have less muscle mass

What would be the benefit of performing a tubular reabsorption test on a patient rather than a creatinine clearance?

Tubular reabsorption tests are not influenced by hydration.

Tubular reabsorption tests provide a more accurate measurement of blood filtration.

Tubular reabsorptions tests diagnose early renal disease.

Tubular reabsorption tests are affected by muscle wasting diseases.

Tubular reabsorptions tests diagnose early renal disease

What is the pigment in urine causing the yellow color?

Urochrome

Urobilin

Uroerythrin

Urea

Urochrome

When a urine sample is shaken, a yellow foam appears. What is causing the yellow foam?

Urobilin

Bilirubin

Protein

Urochrome

Bilirubin

Which of the following is a pathogenic cause of urine turbidity?

Lymph fluid

Semen

Contrast Media

Squamous epithelial cells

Lymph fluid

A urine sample is reported as clear and yellow. Of the following reasons, what could factor into the results as reported?

The specimen is normal.

All of the above.

The patient recently had an imaging study with contrast media.

The patient is taking medicine for a urinary tract infection.

The specimen is normal

As bilirubin breaks down into biliverdin, the color of the urine can become:

orange

yellow-green

blue-green

yellow

yellow-green

What is a typical daily volume of urine?

600-1800 mL

What is the volume (mL) of PLASMA filtered each day

180,000

urine is predominantly made up of

water

Urine formation consists of plasma filtration at the _________, reabsorption and selective secreation by___________

glomeruli, renal tubules

urea, chloride, sodium, potassium, phosphate, sulfate, creatinine, and uric acid are all examples of...

urine solutes

Water has a specific gravity of 1.000. Thus, the lower the specific gravity of urine, the more ____ it is

dilute

Roles of the _____ include:

removal of metabolic wastes

regulation of water and electrolytes

maintenance of body's acid-base equilibrium

kidneys

Urine from each renal pelvis then enters..

ureter

Urine passes from ureter to _______

bladder (serves as a holding area)

When about _____mL of urine accumulates in the bladder, a nerve reflex signal sends an urge to urinate, or contract/relax the urinary sphincter to push urine into urethra leading to outside of body.

150

2 distinct areas of the kidney:

cortex

medulla

Which is the site of filtration?

cortex (glomerulus located in outer cortex is the exclusive site of plasma filtration)

Medulla consists of pyramid-like tissue, each with a duct that enters a

calyx (about 12, then all funnel together)

Calyces funnel urine from collecting tubules to

renal pelvis (then down ureter)

___________ system interacts with tubules

vascular (bowman's capsule very close to distal end of tubules)

There are _____ nephrons in a kidney

millions of

What are the 5 distinct areas in a nephron?

Glomerulus, Proximal Convoluted tubule, loop of henle, distal convoluted tubule, collecting tubule/duct

a capillary tuft surrounded by bowmans capsule, where filtration occurs

glomerulus

Some parts of the nephron are cortical, or within the cortex in the kidney, while others are

juxtamedullary (extend into medulla)

cortical parts of nephron remove waste products and reaborb filtered nutrients. This makes up what percent of the nephron?

85

Juxtamedullary parts of the nephron have longer loops of henle and are responsible for

urine concentration

4 functions of a nephron

renal blood flow, glomerular filtration, tubular reabsorption, tubular secretion

Renal blood flow in mL/min

1200

Renal plasma flow in mL/min

600-700

Kidneys receive what percent of the cardiac output?

25

The renal artery subdivides into capillaries, then reforms as ____ in cortex

arteries (only place in the body where this happens)

The medulla has no direct....

arterial blood supply

An ___________ arteriole supplies blood individually to the glomerulus of each nephron, which branches into a capillary tuft upon entering.

afferent

Capillary tuft within the glomerular capsule of a nephron comes back together to form _______ upon exiting

efferent arteriole

The efferent arteriole branches a second time into a capillary _____

plexus

The driving force behind glomerular filtration is the _________ of afferent arteriole

high hydrostatic pressure

RENAL BLOOD FLOW

enters via renal artery with unusually high bp in the afferent arteriole to the glomerulus, then leaves the glomerulus in the

efferent arteriole

RENAL BLOOD FLOW:

dct, pct, loop of henle, bowman's capsule

bowman's capsule, pct, loop of henle, dct

pct, bowman's capsule, loop of henle, dct

bowman's capsule, loop of henle, pct, dct

bowman's capsule, pct, loop of henle, dct

The space surrounding the loop of henle, thru which blood flows is called the

vasa recta

renal blood flow enters system in _________, glomerulus in _________, leaves glomerulus in ________ occurs in ______, and exits in __________

renal artery, afferent arteriole, efferent arteriole,peritubular capillaries, renal vein

Normal glomerular filtrate in mL/min

120

Ultrafiltrate of plasma (glomerular filtrate) has the.....

same concentration of the solutes in the plasma; minus the proteins. (only really small stuff gets thru)

specific gravity of ultrafiltrate

1.010

filtration pressure is regulated by _____ to maintain consistent glomerular pressure.

arteriole size

In low systemic blood pressure, _________ afferent and ______ efferent

larger, smaller (prevents toxic waste products in blood)

In high systemic blood pressure, ________ afferent and _________ efferent

smaller, larger (prevents overfiltration and glomerular damage)

Large amounts of secretory granules containing the enzyme _____ are present in the afferent arteriole of the juxtaglomerular apparatus, which is close to the filtration system

renin

renin is released in response to

decreased arteriole blood pressure or volume

decreased sodium

increased potassium

vascular hemorrhage

all

none

all

Renin causes ___________ formation and _______ secretion into urine

angiotensin, aldosterone

renin can ______ bp

rise

Aldosterone causes kidneys to retain what to rise blood pressure?

sodium and water

renin-angiotensin-aldosterone system (RAAS) regulates blood flow to and within the _____________. It also responds to changes in blood pressure and plasma sodium

glomerulus

low plasma sodium leading to a decrease in water retention will decrease

blood volume and blood pressure

initiates RAAS in response to blood pressure changes

Macula densa

The Macula densa responds to efferent arteriole, blood leaving. The other cells in the juxtaglomerular apparatus, the juxtaglomerular cells, respond to the

afferent arteriole

Juxtaglomerular cells secrete ____ at DCT

renin

renin reacts with angiotensin to produce

angiotensin 1

Angiotensin 1 passes through lungs and reacts with ACE to form

angiotensin 2

What does all of the following?

Dilates afferent arteriole

constricts efferent arteriole

stimulates sodium reabsorption in PCT

triggers adrenal cortex to release aldosterone

Triggers release of ADH by hypothalamus

Stimulates water reabsorption

angiotensin 2

Reabsorption of sodium in the DCT and collecting duct is stimulated by

aldosterone

Reabsorption of sodium in the PCT is stimulated by

angiotensin 2

Each portion of the _______ has distinctly different epithelial cells related to the function in that anatomical area. They selectively reabsorb substances necessary for body homeostasis and function, such as water, amino acids, salts, and glucose. It doesn't absorb waste products like creatinine.

tubules

secretion occurs to eliminate wastes and substances not normally present in plasma. It also occurs to adjust...

acid-base balance of body

Back to blood

reabsorption

back to urine

secretion

Are tubular transport mechanisms active or passive?

both

In ACTIVE transport of tubular reabsorption, substances require energy to move against gradient and carrier proteins transfer substances back to the bloodstream. T/F

true

What is ACTIVELY REABSORBED in the proximal convoluted tubule?

glucose, salts, and amino acids

What is ACTIVELY REABSORBED in the loop of henle?

chloride (in ascending loop)

What is ACTIVELY REABSORBED in the distal convoluted tubule?

sodium

Tubular reabsorption using passive transport is controlled by substance concentration gradients on opposite sides of a membrane. What is passively reabsorbed throughout the nephron?

WATER (except in ascending loop of henle)

Part of the nephrone impermeable to water; accompanies high amount of sodium reabsorption in pct

ascending loop of henle

What is PASSIVELY REABSORBED in the ascending loop of henle

sodium and urea

What is PASSIVELY REABSORBED in the PCT

urea

Tubular conentration begins in the descending and ascending loops of henle, which is exposed to a high osmotic gradient. In the DESCENDING loop of henle, what is removed by passive transport?

water

In the ascending loop of henle, walls are impermeable to water, chloride is reabsorbed _______ and sodium is reabsorbed _______. This countercurrent mechanism maintains the osmotic gradient.

actively, passively

Renal concentration- collecting duct concentration.

The final filtrate concentration occurs where?

DCT

Final filtrate concentration occurs by

water reabsorption

water reabsorption is controlled by what in response to body hydration?

ADH (vasopressin)

ADH (vasopressin) controls water reabsorption by controlling the premeability of what walls to water?

DCT and CD

The release of ADH is controlled by ____________ feedback with arterial blood pressure and ___________ feedback with plasma osmolality

negative, positive

The passage of substances from the blood in the peritubular capillaries to the filtrate

tubular secretion

2 functions of tubular secretion

eliminate non-filtered wastes and regulate acid-base balance

Tubular secretion regulates acid-base balance by secretion of_____ ions to return filtered buffers to the blood

hydrogen

ADH produced by hypothalamus (regulated by vasopressin) is released into the blood from the ___________ and determines the permeablitity of tubule epithelium.

posterior pituitary gland

Blood pH reference range

7.35-7.45

The blood bicarbonate buffer system, the pulmonary system, and the renal system are the three body systems involved in the maintenance of

pH

In the blood bicarbonate buffer system, buffers prevent

pH change

In the pulmonary system, lungs can exhale or retain carbon dioxide, an acid, to affect

pH

To affect/regulate body's blood pH, the _______ system:

-increases or decreases excretion of H+

-increases or decreases formation of ammonia

-increases or decreased reabsorption of bicarbonate

renal

The secretion of H+ into filtrate by the renal tubular cells prevents excretion of bicarb, which is returned to plasma. This affects the body's

acid-base balance