Answer:E) Voltage-gated calcium channels open
F) Calcium enters the synaptic knob
G) Synaptic vesicles merge with synaptic knob plasma membrane
H) Neurotransmitter is released by exocytosis
B) Neurotransmitter attaches to receptors on a muscle, neuron, or gland cell
I) Action potential reaches synaptic knob
Explanation:
The best answer is D.
Facilitated diffusion is a transport mechanism in which carrier proteins shuttle molecules across a plasma membrane without using the cell's energy . The energy is provided by the concentration gradient i.e. molecules are transported from higher to lower concentrations, into or out of the cell.
Glucose binds to carrier proteins of the GLUT family. Once bound, the change shape so as to fit in the membrane channels and thus they translocate the glucose molecule from one side of the plasma membrane to the other.
Answer:
Free radicals are unstable atoms that can damage cells, causing illness and aging. Free radicals are linked to aging and a host of diseases, but little is known about their role in human health, or how to prevent them from making people sick.
Explanation: