Simple....
as you've learned... cells create tissue..tissue creates organs...organs create organ systems..and organ systems create organisms. They all work together to create something...
An example:
muscle cell-->>muscle tissue-->>heart-->>circulatory system-->>the circulatory system makes up a part of the body.
Thus, your answer.
Answers;
Cellular respiration;
Explanation;
Food molecules contain biochemical energy which is made available by cellular respiration;
The process of cellular respiration takes in food and uses it to create ATP, a chemical which the cell uses for energy.
The purpose of cellular respiration is to provide cells with the energy they need to functioning and activities such as growth and movement.
Answer:
Option A, Key stone
Explanation:
A keystone species plays a major role in an ecosystem as it is the species whose presence effects all other species in the ecosystem .In general a keystone species is always a dominant predator that feed on prey population. If it is removed, the prey population will explode and the population diversity will reduce. For example - bison, prairie dog etc.
Hence, option A is correct
I would think it would be C