Answer;
-Central nervous system
Explanation;
-The nervous system consists of two main parts: the central nervous system and the peripheral nervous system: The central nervous system is made up of the brain and spinal cord.
-The central nervous system controls most functions of the body and mind.It controls all parts of the body. It receives and interprets messages from all parts of the body and sends out instructions. The brain is the center of our thoughts, the interpreter of our external environment, and the origin of control over body movement.
-The spinal cord serves as a conduit for signals between the brain and the rest of the body and also controls simple musculoskeletal reflexes without input from the brain.
Answer:
scientific theory is the answer
Answer:
What is the effect of power/magnification on the frequency and size of organelles under a microscope?
Explanation:
Organelles within the cell are responsible for carrying out various functions. Some cells are more specialized than others, and may have particular organelles at a higher frequency, or showing a variation in size; sub-cellular structures become more visible at higher magnifications under the microscope.
Hypotheses:
- organelle A's frequency decreases while B's frequency increases at higher magnifications
- organelle A's size increases while B's size decreases at higher magnifications
<em />
<em>Dependent variables: size and frequency cell organelles</em>
<em>Independent variable: power/magnification at low (x4), medium(x10) and high (x40)</em>
<em>Controlled variables: Type of organelles, microscope used, cell examined, </em>
Method:
1. Examine the organelles A and B in a cell mounted on a slide; use the fine adjustment to focus on the cell.
- Frequency: What is the average number of organelle A versus B, seen at low (x4), medium (x10) and high (x40) magnifications?
- Size: Measure the average diameter of organelle A versus B using an ocular micrometer at low, medium and high magnification.
2. Record and tabulate observations.
Answer:
It's 3!
Explanation:
There must be genetic differences so the best fitted organisms will survive. If they were all the same then no one would be best fitted and Natural Selection wouldn't be able to occur
It's not 1 because a food shortage isn't required, there's always competition for food sources
It's not 2 because there doesn't need to be a change in the environment for natural selection, just for evolution.
And it can't be 4 if 1 and 2 are wrong!
Hope this helped!