Ch 44 Osmoregulation and Excretion

Question 1

Osmoregulation

Answer 1

The maintenance of internal solute concentrations and water levels within a range that allows cellular functions to continue

Question 2

Osmosis

Answer 2

Water moves across a membrane from where it is more concentrate (relative to solutes) to where it is less concentrated

Question 3

Osmotic conformers

Answer 3

Animals that do no actively regulate osmotic pressure of their body fluids

Question 4

Why are most marine invertebrates osmotic conformers?

Answer 4

They are in a stable environment

Question 5

Why do most invertebrates actively osmoregulate?

Answer 5

They are in less stable environments

Question 6

Animals can modify behavior to limit what?

Answer 6

Water loss

Question 7

In what two kind of environments is water loss a major problem?

Answer 7

1) Terrestrial

2) Temporary aquatic

Question 8

How do terrestrial vertebrates regulate their water balance physiologically?

Answer 8

1) Consuming water
2) Consuming moist foods
3) Acquiring water through metabolism

Question 9

Water molecules are one of the final products of what?

Answer 9

The electron transport chain

Question 10

What purpose do salt glands in marine reptiles serve?

Answer 10

Reduce osmotic pressure by removing salt from the blood

Question 11

What can greatly effect an animal’s water balance?

Answer 11

The type and amount of its waste

Question 12

What is one of the most important wastes?

Answer 12

Nitrogenous breakdown products of proteins and nucleic acids

Question 13

Ammonia (NH4)

Answer 13

The primary nitrogenous waste of metabolism

Toxic except in very dilute form

Question 14

Terrestrial vertebrates convert ammonia to what?

Answer 14

Less toxic wastes

Question 15

Why do terrestrial vertebrates convert ammonia into les toxic wastes?

Answer 15

They can be concentrated in the body an excreted with less water

Question 16

Why do sharks and rays concentrate urea in their tissues?

Answer 16

To increase the body’s osmotic pressure and retain water from the environment

Question 17

Metanephridia

Answer 17

Secrets wastes and reabsorbs solutes

Possessed by terrestrial coelomates (annelids and molluscs)

Question 18

Insects and spiders posses what kind of excretion?

Answer 18

Malphigian tubule excretion (not associated with blood circulation)

Question 19

Malpighian tubule

Answer 19

Hydrogen ions are actively pumped into the tubules

The increased osmotic pressure draws in salts, water, and wastes which are passed into the intestine

Question 20

Kidney

Answer 20

Primary organ regulating volume and composition of body fluids in vertebrates

Question 21

Urine is formed as a result of what?

Answer 21

Three physiological processes that take place across the cortex and medulla of the kidney

Question 22

Three physiological processes that form urine

Answer 22

1) Filtration
2) Reabsorption
3) Secretion

Question 23

Nephron

Answer 23

The basic functional unit of the kidney

Question 24

Glomerulus

Answer 24

Found in the nephron of the kidney

Water and small solutes, but no proteins and red blood cell, can pass through this structure

Question 25

Proximal tubule

Answer 25

Found in the nephron of the kidney

Where most of the water and glucose are reabsorbed

Question 26

Distal tubule

Answer 26

Found in the nephron of the kidney

Hydrogen, potassium, and foreign molecules (including drugs) are secreted into this structure

Question 27

What process in the kidney changes osmolarity and facilitates additional water absorption?

Answer 27

Transport of salts from the nephron to the interstitial fluid

Question 28

The mammal kidney allows for the production of urine that is what?

Answer 28

More concentrated than the blood