Answer:
The human cell system has a pretty advanced and effective way of communication. This communication between cells, whether it be of a single system, or between systems, is carried out by chemical reactions and gradients, and also through the intercession of molecules known as neurotransmitters. This is the case of the nervous system and its means of communication.
When we talk about neurotransmitters (the messengers) and neuroreceptors (the gatekeepers that receive the message and produce a reaction), we are literally talking about communication in the nervous system.
There are two types of neuroreceptors for trasmitters: the ionotropic (ligand-gated ion channels) and the metabotropic (second-messenger gated receptors, or G-protein coupled receptors). While the first type depends entirely on the availability of a ligand that binds to the receptor to open up the influx of ions from outside and inside of the cell to create a gradient that will ensure a cell response, the second does not open any ion channels and literaly what it does is receive the message from a neurotransmitter, and through the G-protein bound to the receptor, once it gets the necessary message, detaches and carries out the information to the cell. This is broadly how neurotransmittion can be carried out in the nervous system.
I think the correct answer would be e.coli
Cell division and differentiation first begins during the germinal stage of prenatal development.
<u>Explanation:</u>
The development of the zygote into a full developed fetus occurs in three most prominent stages they are the germinal stage that occurs from the conception to the second week.
The embryonic stage that is from second week to the eighth week and the fetal stage that is from the eighth week till the birth of the baby. Each stage has its characteristic development that has to be completed.
Hi!
The selection in this case would be natural selection.
Natural selection is a process that involves organisms with favorable characteristics having a higher chance of reproductive success, and passing on their traits onto the offspring. This process, as opposed to artificial selection, does not involve human intervention and is a natural phenomenon.
In our case, whales with maximum length (the favorable trait) are mating on accord of their own, without external factors governing the process; hence, the selection is natural.
Hope it helps!
