BIOL 1442 CHAPTER 44 PART 1

The osmoregulatory/excretory system of an insect is based on the operation of

Malpighian tubules

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

direct cellular exchange-marine invertebrate

Birds that live in marine environments and thus lack access to fresh drinking water

drink sea water and secrete excess ions mainly through their nasal salt glands

Excretory structures known as protonephridia are present in

flatworms

Many marine and fresh water bony fish achieve osmoregulation via

gain of water through food

Excessive formation of uric acid crystals in humans leads to

gout a painful inflammatory disease primarily affects the joints

Excretory organs known as Malpighian tubules are present in

insects

Which of the following pairs of organisms excrete nitrogenous wastes in the form of uric acid?

insects and birds

Among vertebrate animals, urea

is made in the liver by combining two ammonia molecules with one carbon dioxide

Ammonia

is soluble in water

Compared to the seawater around them, most marine invertebrates are

isoosmotic

The body fluids of an osomoconformer would be _____ with its _____ environment

isoosmotic; saltwater

A necropsy (postmortem analysis) of a marine sea star that dieed after it was mistakenly placed in fresh water would likely show that it died because

it was so hyperosmotic to the fresh water that it could not osmoregulate

Among the following choices, the most concentrated urine is excreted by

kangaroo rats

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

kidneys of the vertebrates

Urea is produced in the

liver from NH3 and CO2

A necropsy (postmortem analysis) of a freshwater fish that died after being placed accidentally in saltwater would likely show that

loss of water by osmosis from cells in vital organs resulted in cell death and organ failure

Ammonia is likely to be the primary nitrogenous waste in living conditions that include

lots of fresh water flowing across the gills of fish

Organisms catergorized as osmoconformers are most likely

marine

The osmoregulatory/excretory system of an earthworm is based on the operation of

metanephridia

Fresh water flatworms form a urine that is typically

of low solute concentration and of high volume, matching their normal fluid uptake

In animals, nitrogenous wastes are produced mostly from the catabolism of

proteins and nucleic acids

The osmoregulatory/excretory system of a fresh water flatworm is based on the operation of

protonephridia

Birds excrete uric acid as their nitrogenous waste because uric acid

requires little water for nitrogenous waste disposal, thus reducing body mass

The fluid with the highest osomolarity is

sea water in a tidal pool

The osmoregulatory process called secretion refers to the

selective elimination of excess ions and toxins from body fluids

Materials are returned to the blood from the filtrate by which of the following processes?

selective re absorption

Urea is

the primary nitrogenous waste product of humans

Unlike most bony fish, sharks maintain body fluids that are isoosmotic to sea water, so they are considered to by many to be osmoconformers. Nonetheless, these sharks osmoregulate at least partially by

tolerating high levels of urea concentrations that balance internal salt concentrations to sea water osmolarity

the advantage of excreting nitrogenous wastes as urea rather than ammonia is that

urea is less toxic than ammonia

The nitrogenous waste that requires the most energy to produce is

uric acid

The primary nitrogenous waste excreted by birds is

uric acid

Which nitrogenous waste has the greatest number of nitrogen atoms?

uric acid

Which nitrogenous waste requires hardly any water for its excretion?

uric acid

Osmoconforming sharks take in water, as needed,

via osmosis, as their body cells are slightly hyperosmotic to sea water

A human who has no access to fresh water but is forced to drink sea water instead

will excrete more water molecules than taken in, because of the high load of ion ingestion