the believe they move inside the membrane which is creating a gradient
C!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
The correct answer is - the variable.
With the experiment, in the way that Dan had decided to perform it, the fertilizer is the variable, as in one of the parts with strawberries he uses fertilizer, while in the other part he doesn't uses fertilizer.
While this kind of experiment may give Dan some answers, and he might notice differences, still he would have to be more detailed in the experiment to see for sure if the fertilizer is the thing that makes some of the strawberries grow better than the others.
Dan should also put all of the strawberries at places that would receive the same amount of light, experience the same weather conditions, receive the same amount of water, and to be planted in a soil of the same quality. Only like this, after putting the fertilizer, Dan can now if it makes any changes or not.
Answer:
b. neuron, nerve tissue, brain, nervous system, human
Explanation:
Neurons are the structural and functional units of nervous tissue. Each neuron has a long axon, a metabolic center (soma) and short dendrites. Neurons and neuroglia are the major cell types that together constitute the nervous tissue.
The brain is an organ made of nervous tissues and is a part of the central nervous system. The central and peripheral nervous systems together make the nervous system of the human body.
The nervous system along with many other organ systems such as the digestive system, respiratory system, cardiovascular system, etc. together make the human body.