Pretty sure its d... hope this helps
Neurotransmitters. With the regard to the process of the neural transmission, a refractory period refers to the time in interval in which. the Positively charged sodium ions are to pumped back to outside a neural membrane.
Neurotransmitters are the chemical messengers that your body can't function without it. Their job is to carry out chemical signals (“messages”) from one of the neuron (nerve cell) to the next target cell. The next target of the cell can be another nerve cell, a muscle cell or the gland.
Fortunately, the seven “small molecule” are neurotransmitters (acetylcholine, dopamine, the gamma-aminobutyric acid (GABA), or glutamate, histamine, norepinephrine, and the serotonin) do the majority of the work.
To know more about Neurotransmitters visit:
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The digestive system uses mechanical and chemical methods to break food down into nutrient molecules that can be absorbed into the blood. ... Some animals ues intracellular digestion, where food is taken into cells by phagocytosis with digestive enzymes being secreted into the phagocytic vesicles.
206 bones
I hope this helps :)
Answer:
there is an association between the number of mitochondria in muscle cells and energy production
Explanation:
Mitochondria generate energy by generating adenosine triphosphate (ATP), which is referred to as the "molecular unit of currency" of the cell since this molecule provides energy for diverse cellular processes
