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.
Answer:
A landform is a feature on the Earth's surface that is part of the terrain. Tectonic plate movement under the Earth can create landforms by pushing up mountains and hills. Erosion by water and wind can wear down land and create landforms like valleys and canyons.
Answer:
Gametogenesis is the process whereby a haploid cell (n) is formed from a diploid cell (2n) through meiosis and cell differentiation. Gametogenesis in the male is known as spermatogenesis and produces spermatozoa. Gametogenesis in the female is known as oogenesis and result in the formation of ova.
Explanation:
found the answer hopes this helps ^_^
This is referring to meiosis, which happens just once to make reproductive cells, unlike mitosis which is just simple copying.
In mitosis, one cell splits into two, but the number of chromosomes doesn't change. The original cell makes two copies of its chromosomes and divides them up.
In <em>meiosis</em>, however, our cell doesn't bother making those two copies. It just takes what it has and divides it between two new cells.
