Answer:
D.-
Explanation:
A control group is needed to carry out the experiment, that control group is the one that is not injected with anything. Ethanol and pesticide need to be injected into separated groups to document whether it is one or the other that is harmful
The muscles that contract (during cold or fright), the slanted hair follicle is pulled upright, dimpling the skin surface with goosebumps are called arrector pili muscle.
The arrector pili muscle are tiny muscle that attaches to the base of the hair follicle at one end and to the dermal tissue on the other end. When the body feels cold or fright the body generate heat and the arrector pili muscle contract all at once, that causes goosebumps on the skin.
The arrector pili muscle acts as the thermoregulator. Straight stand hair increases air trapping, so that the heat loss from the body decreases. The arrector pili muscle are mediated by the sympathetic nervous system.
To learn more about sympathetic nervous system here
brainly.com/question/12958051
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Alexander l.oparin I looked it up !
<h2>Answer:</h2>
Option B is correct.
B. In an exothermic reaction, excess energy is released as heat.
<h2>Explanation:</h2>
An exothermic reaction is a chemical reaction that releases energy by light or heat. It is the opposite of an endothermic reaction. Expressed in a chemical equation: reactants → products + energy. Exothermic Reaction means "exo" meaning releases and "thermic" means heat.
Adenine, Guanine, Cytosine, Thymine?
