Evolution of the kidney

Question 1

What are the 5 important ions involved in osmolality?

Answer 1

Sodium, Chloride, Calcium, Magnesium and Potassium

Question 2

What is osmotic pressure?

Answer 2

Measure of a solution’s tendency to take in water by osmosis

Question 3

What is tonicity?

Answer 3

Measure of a solution’s ability to change the volume of a cell by osmosis.
Solutions may be hypertonic, hypotonic or isotonic

Question 4

What are osmoconformers?

Answer 4

Organisms that are in an osmotic equilibrium with their environment
Hagfish are the only strict conformers

Question 5

What are osmoregulators?

Answer 5

Maintain a relatively constant blood osmolarity despite different concentrations in their environment

Question 6

What are the major functions of the kidneys?

Answer 6

Maintenance of proper solution concentrations, maintenance of proper blood volume, removal of metabolic end products and removal of foreign substances or their metabolic end products.

Question 7

What are the general excretory organs?

Answer 7

Contractile vacuoles, invertebrate nephridial organs, malpighian tubules (insects) and kidneys

Question 8

What are specialised excretory organs?

Answer 8

Gills, rectal and salt glands, liver and the intestine

Question 9

What is the only bird to have a urinary bladder?

Answer 9

Ostrich

Question 10

What are some of the reasons reptiles and birds produce uric acid?

Answer 10

Saving water, decreasing weight and they lay eggs - concentrated nitrogenous wastes would be fatal for the embryo.