Plants produce oxygen this oxygen gas which is important part of our air is gas that plants and animals must have in order to stay alive when people breeze it's the auction that we take out of the air into our cells and blood is there taking into the alveoli and this is where gas exchange takes place all the o2 available for living organisms come from plants
The correct answer is A. Experimental group
Explanation:
In experiments, the experimental group refers to the group of subjects that receives special treatment or in which the scientist or researcher intervenes. This is the opposite of a control group that does not receive treatment and therefore, it is used as a reference to measure the effect of the treatment.
This implies, in the experiment presented Group A is the control group as they do not have special treatment because they sleep normally and Group B is the experimental group as the researcher modifies their sleep time and reduces it two hours which means in this group there is a treatment or intervention.
Answer: Certain proteins
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