A. during cellular respiration
explanation:
~ During daylight hours, plants take in carbon dioxide and release oxygen through photosynthesis, and at night only about half that carbon is then released through respiration.
A. Nutrients and other materials pass through the cell membrane through the process of diffusion. This allows the cell to perform all the activities it requires for daily maintenance and living. The concentration gradient allows the cell to regulate just how much of a certain material passes through it.
Chromosomes is the answer
Because neurones will not function properly neither will neuroreceptors if a person lacks neurotransmitters, these two parts (transmiters and receptors) all work together and depend on eachother.
Neurones are resposible for transmitting informations trought the body, and if neurotransmitters are no-existent, information may not be able to get to some body parts since neurotransmitters transmit the information.
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