In the small intestine, these cells contain microvilli, which are tiny hair-like projections that increase nutrient absorption. These projections increase the surface area of the small intestine allowing more area for nutrients to be absorbed.
Functions of cell surface Receptors .
most ligands responsible for cell-cell signaling ( including neurotransmitters, peptide, hormones, and growth factors) bind to receptors on the surface of their target cells.
Answer:
False.
Explanation:
Neurotransmitter release occurs from the nervous terminal or varicosities in the neuronal axon. When an action potential reaches the nervous terminal, the neurotransmitter is released by exocytose. The molecule binds to its receptor in the postsynaptic neuron, triggering an answer. As long as the signal molecule is in the synaptic space, it keeps linking to its receptor and causing a postsynaptic response. To stop this process the neurotransmitter must be taken out from the synaptic space. There are two mechanisms by which the neurotransmitter can be eliminated:
• Enzymatic degradation/deactivation: There are specific enzymes in the synaptic space, which are in charge of inactivating the neurotransmitter by breaking or degrading it. The enzyme acetylcholinesterase prevents ACh from continuing to stimulate contraction.
• Reuptake: Receptors located in the presynaptic membrane can capture de molecule to store it back in new vesicles for posterior use. These transporters are active transport proteins that easily recognize the neurotransmitter.
De answer is A!!!!!!!!!!!!!!!!!!!!!!!!!!!!
hope it helps!!!!!!!!!!!!!!!!!
a is right!!!!!!!!!!!!!
<span>The cell could not function with 2 nuclei.
Hope this helps!
-Payshence xoxo</span>
