Answer:
Single-celled organism are not classified as an animal because animals are multicellular organisms i. e. made of more than one cell while single celled organisms are unicellular organisms i. e. made of one cell. In single celled organisms, one cell perform all activities while in animals special cells are responsible for particular function. There are some single celled organisms are autotrophic while animals are heterotrophic in nature.
The fill in the blank answer is increased
Upwelling is a process in which cold water from depths arise to the surface,
it's important because :
- It bring a lot of nutrients to the surface of the ocean
- It maintain the temperature of the ocean
hope this helps
