Which process in the nephron is least selective?
A) filtration
B) reabsorption
C) active transport
D) secretion

A

What is the function of the osmotic gradient found in the kidney? The osmotic gradient allows for _____.

A) electrolytes to move from low to high concentrations in the absence of ATP

B) the precise control of the retention of water and electrolytes

C) the loop of Henle to deliver water to the renal vein

D) the filtration of large cells at the glomerulus

B

The loop of Henle dips into the renal cortex. This is an important feature of osmoregulation in terrestrial vertebrates because _____.

A) absorptive processes taking place in the loop of Henle are hormonally regulated

B) differential permeabilities of ascending and descending limbs of the loop of Henle are important in establishing an osmotic gradient

C) the loop of Henle plays an important role in detoxification

D) additional filtration takes place along the loop of Henle

B

Low selectivity of solute movement is a characteristic of _____.

A) H + pumping to control pH

B) reabsorption mechanisms along the proximal tubule

C) filtration from the glomerular capillaries

D) secretion along the distal tubule

C

If ATP production in a human kidney was suddenly halted, urine production would
A) come to a complete halt.
B) decrease, and the urine would be hypoosmotic compared to plasma.
C) increase, and the urine would be isoosmotic compared to plasma.
D) increase, and the urine would be hyperosmotic compared to plasma.
E) decrease, and the urine would be isoosmotic compared to plasma.

C

Compared to wetland mammals, water conservation in mammals of arid regions is enhanced by having more
A) juxtamedullary nephrons.
B) Bowman's capsules.
C) ureters.
D) podocytes.
E) urinary bladders.

A

Processing of filtrate in the proximal and distal tubules
A) maintains homeostasis of pH in body fluids.
B) regulates the speed of blood flow through the nephrons.
C) reabsorbs urea to maintain osmotic balance.

C

In humans, the transport epithelial cells in the ascending loop of Henle
A) are the largest epithelial cells in the body.
B) are not in contact with interstitial fluid.
C) have plasma membranes of low permeability to water.
D) have 50% of their cell mass made of smooth endoplasmic reticulum.
E) are not affected by high levels of nitrogenous wastes.

C

The high osmolarity of the renal medulla is maintained by all of the following except
A) diffusion of salt from the thin segment of the ascending limb of the loop of Henle.
B) active transport of salt from the upper region of the ascending limb.
C) the spatial arrangement of juxtamedullary nephrons.
D) diffusion of urea from the collecting duct.
E) diffusion of salt from the descending limb of the loop of Henle.

E

Natural selection should favor the highest proportion of juxtamedullary nephrons in which of the following species?
A) a river otter
B) a mouse species living in a tropical rain forest
C) a mouse species living in a temperate broadleaf forest
D) a mouse species living in a desert

D

If you are hiking through the desert for several days, one would pack which of the following to ensure proper hydration?

A) a drink with a combination of water and electrolytes
B) caffeinated beverages
C) bottled water kept at room temperature
D) bottled water that had been frozen to ensure that it would be as cold as possible

A

Increased antidiuretic hormone (ADH) secretion is likely after _____.

A) drinking lots of pure water
B) sweating-induced dehydration increases plasma osmolarity
C) eating a small sugary snack
D) blood pressure becomes abnormally high

B

After blood flow is artificially reduced at one kidney, you would expect that kidney to secrete more of the hormone known as _____.

A) angiotensinogen
B) renin
C) antidiuretic hormone
D) atrial natriuretic peptide

C

After drinking alcoholic beverages, increased urine excretion is the result of _____.

A) increased aldosterone production
B) increased blood pressure
C) inhibited secretion of antidiuretic hormone (ADH)
D) increased reabsorption of water in the proximal tubule

C

Osmoregulatory adjustment via the renin-angiotensin-aldosterone system can be triggered by _____.

A) sleeping for one hour
B) severe sweating on a hot day
C) eating a pizza with olives and pepperoni
D) drinking several glasses of water

B

Antidiuretic hormone (ADH) and the renin-angiotensin-aldosterone system (the RAAS) work together in maintaining osmoregulatory homeostasis through which of the following ways?

A) ADH regulates the osmolarity of the blood by altering renal reabsorption of water, and the RAAS maintains the osmolarity of the blood by stimulating Na+ and water reabsorption.
B) ADH and the RAAS work antagonistically; ADH stimulates water reabsorption during dehydration and the RAAS causes increased excretion of water when it is in excess in body fluids.
C) Both stimulate the adrenal gland to secrete aldosterone, which increases both blood volume and pressure via its receptors in the urinary bladder.
D) ADH and the RAAS combine at the receptor sites of proximal tubule cells, where reabsorption of essential nutrients takes place.

A

A fruit fly, internally infected by a potentially pathogenic fungus, is protected by
A) its plasma cells.
B) its immunoglobulins.
C) its antibodies.
D) its antimicrobial peptides.
E) its B cells.

D

Engulfing-phagocytic cells of innate immunity of vertebrates include _____.

I) neutrophils
II) macrophages
III) dendritic cells
IV) natural killer cells

A) I and III
B) II and IV
C) I and IV
D) I, II, and III

B

The cells and signaling molecules involved in the initial stages of the inflammatory response are _____.

A) phagocytes and chemokines
B) dendritic cells and interferons
C) mast cells and histamines
D) lymphocytes and interferons

C

Inflammatory responses typically include _____.

A) increased activity of phagocytes in an inflamed area
B) reduced permeability of blood vessels to conserve plasma
C) release of substances to decrease the blood supply to an inflamed area
D) inhibiting the release of white blood cells from bone marrow

A

Mammals have Toll-like receptors (TLRs) that can recognize a kind of macromolecule that is absent from vertebrates but present in or on certain groups of pathogens, such as viral _____.

A) double-stranded DNA
B) double-stranded RNA
C) glycoproteins
D) phospholipids

B

Septic shock, a systemic response including high fever and low blood pressure, is a response to _____.

A) certain bacterial infections
B) specific forms of viruses
C) the presence of natural killer cells
D) increased production of neutrophils

A

who is the best person ever

a. london

b. kat

c. sammy

d. k hoe

e. alexis

f. all the above

A.

Materials are returned to the blood from the filtrate by which of the following processes?
A) filtration
B) ultrafiltration
C) selective reabsorption
D) secretion
E) active transport

C

Excretory structures known as protonephridia are present in
A) flatworms.
B) earthworms.
C) insects.
D) vertebrates.
E) cnidarians.

A

The osmoregulatory process called secretion refers to the
A) formation of filtrate at an excretory structure.
B) reabsorption of nutrients from a filtrate.
C) selective elimination of excess ions and toxins from body fluids.
D) formation of an osmotic gradient along an excretory structure.
E) expulsion of urine from the body.

C

The osmoregulatory/excretory system of an earthworm is based on the operation of
A) protonephridia.
B) metanephridia.
C) Malpighian tubules.
D) nephrons.
E) ananephredia.

B

Choose a pair that correctly associates the mechanism for osmoregulation or nitrogen removal with the appropriate animal.

A) metanephridium — flatworm
B) Malpighian tubule — frog
C) flame bulb — snake
D) exchange across the body surface — marine invertebrate

D

An excretory system that is partly based on the filtration of fluid under high hydrostatic pressure is the _____.

A) flame bulb system of flatworms
B) protonephridia of rotifers
C) Malpighian tubules of insects
D) kidneys of vertebrates

D