Answer:
It's important for a scientist to try to hold all variables constant except for the independent variable. If a control variable changes during an experiment, it may invalidate the correlation between the dependent and independent variable. When possible, control variables should be identified, measured, and recorded.
Simulations generally involve a simple design. In contrast, the world is a very complex system. Many events, such as how we farm, can disrupt the world's delicate balance. Simulations do not take into account the varied interactions that affect events in the real world.
Answer:
B
Explanation:
Nerve cells can carry signals and connect all parts of the body to the brain
Answer:
I believe it's <em>size</em>
Answer: Animals and fungi share a common ancestor and branched away from plants at some point about 1.1 billion years ago.
