Many unicellular algae like Chlamydomonas live in water. How do they take in oxygen for respiration?

Correct option is D

The correct answer is (D)  ​They absorb dissolved oxygen via diffusion like Amoeba.

• ​Chlamydomonas is a small, unicellular green alga commonly found in freshwater.
• It performs various functions essential for survival through simple processes like diffusion and photosynthesis.​
  

Information booster:

Key Features of Chlamydomonas:

• Respiration: Chlamydomonas takes in oxygen from the surrounding water through diffusion.

• Photosynthesis: It is a photoautotroph, meaning it uses sunlight to produce carbohydrates as food.

• Survival Without Oxygen: In the absence of oxygen, Chlamydomonas can switch to anaerobic metabolism for energy.

• Maintaining Cellular Balance: It uses substances like ascorbate and glutathione (GSH) to keep cellular redox balance.

• Movement: Chlamydomonas moves with the help of two whip-like structures called flagella.

Reproduction

• It reproduces asexually by dividing into two cells.
• It can also reproduce sexually by fusing with another cell to form a zygote.