Adaptations of Gas Exchange Surfaces

Question 1

Across the Body Surface of a Single-celled Organism

Chlamydomonas is a ……………………………………. It is spherical in shape and has a diameter of 20μm. Oxygen can diffuse across the cell wall and cell surface membrane of Chlamydomonas

The maximum distance that oxygen molecules would have to diffuse to reach the centre of a Chlamydomonas is 10μm, this takes 100 milliseconds

……………….. is an efficient exchange mechanism for Chlamydomonas

Answer 1

single-celled organism that is found in fresh-water ponds

Question 2

Effective exchange surfaces in organisms have

Answer 2

A large surface area

Short diffusion distance

Concentration gradient (maintained