Exchange of gases in fish is very efficient because of: the large surface area of the gills. the large surface area of the blood capillaries in each gill filament. the short distance required for diffusion – the outer layer of the gill filaments and the capillary walls are just one cell thick.
Answer:
The correct answer is d. Oxygen
Explanation:
Phytoplanktons are responsible for the fixation of approximately half of the global carbon therefore seawater has high CO2 concentration which is required by phytoplanktons to make their food.
They are the primary producers of oceans and they are responsible to support the food chain of oceans. Factors that can limit their growth are mainly sunlight and nutrients like phosphorus, nitrogen, etc.
As phytoplanktons are photosynthetic they release oxygen itself as a byproduct therefore oxygen is not a limiting factor to phytoplanktons. So the right answer is d.
This tobacco plant is an example of a genetically modified organism.
