Ans.
Cell-to-cell communication allows signalling of essential substances between the plant cells, which are surrounded by cell walls. The molecules used by plants for long-distance signalling are known as hormones, such as auxin, ethylene, and gibberelin.
These hormones are secreted by one plant cell and received by another plant cell, where it exerts it affect. Thus, the correct answer to be fill in the blank is 'option A). hormones.'
Answer:
The answer is motor end plate.
Explanation:
<em>The region of the sarcolemma across from the axon terminal at the neuromuscular junction is the motor end plate.</em>
First, we can eliminate 2 options. The simple unit of protein is amino acid, instead, the simple unit of fat and lipids are fatty acids and glycerol, therfore we can eliminate option A and D because fatty acids does not exist in protein.
Now we are left with B and C. To solve that, we need to understand that protein is made of a chain of amino acids, a lot of amino acids are chemically combined and cannot be broken down unless the use of enzymes. Amino acid are actually the monomers that forms protein.
Therefore, the answer is C. amino acid combine to form a protein chain.
Exchanging oxygen and carbondioxide between air and lungs because it just involves breathing system but everything else involves hormones.........
HOPE IT HELPS !!!
