Which is a primary disturbance

What maintain homeostasis when a persons internal body temperature is 97.5°f

Which part of the neuron below is indicated by the arrow, and what is its function? hormones send chemical signals throughout the body to regulate other body processes. hormones are chemical signals that are sent throughout the body to regulate other body processes. hormones send electrical signals throughout the body to regulate other body processes. hormones are electrical signals that are sent throughout the body to regulate other body processes.

Which of these parts of the membrane large moecules pass through it ?