Answer: Cells have receptors because Receptors let the cell know when to let things in and out of the cell.
Explanation:
Cell receptors also called transmembrane receptors are proteins located on the surface of a cell (extracellularly) or inside the cell which receive signals that alters the functions of the cell. The functions of the cells which can be altered includes the alteration in gene transcription and the cell morphology.
Cell receptors are generally categorizes into the following groups:
--> Internal receptors
--> cell surface receptors
--> ion channel receptors
--> G protein coupled receptors
--> enzyme linked receptors
Interaction of cell membrane receptors with specific ligands that bonds to the receptors causes conformational changes in the receptor protein. This in turn, enzymatically activates the intracellular part of the protein or induces interactions between the receptor and the proteins in the cytoplasm that act as second messengers, thereby relaying the signal from the extracellular part of the receptor to the interior of the cell. This enables the cell to know when to let things in or out of it through the information conveyed.
Answer:
I = 4.75 A
Explanation:
To find the current in the wire you use the following relation:
(1)
E: electric field E(t)=0.0004t2−0.0001t+0.0004
ρ: resistivity of the material = 2.75×10−8 ohm-meters
J: current density
The current density is also given by:
(2)
I: current
A: cross area of the wire = π(d/2)^2
d: diameter of the wire = 0.205 cm = 0.00205 m
You replace the equation (2) into the equation (1), and you solve for the current I:
![\frac{I}{A}=\frac{E(t)}{\rho}\\\\I(t)=\frac{AE(t)}{\rho}](https://tex.z-dn.net/?f=%5Cfrac%7BI%7D%7BA%7D%3D%5Cfrac%7BE%28t%29%7D%7B%5Crho%7D%5C%5C%5C%5CI%28t%29%3D%5Cfrac%7BAE%28t%29%7D%7B%5Crho%7D)
Next, you replace for all variables:
![I(t)=\frac{\pi (d/2)^2E(t)}{\rho}\\\\I(t)=\frac{\pi(0.00205m/2)^2(0.0004t^2-0.0001t+0.0004)}{2.75*10^{-8}\Omega.m}\\\\I(t)=4.75A](https://tex.z-dn.net/?f=I%28t%29%3D%5Cfrac%7B%5Cpi%20%28d%2F2%29%5E2E%28t%29%7D%7B%5Crho%7D%5C%5C%5C%5CI%28t%29%3D%5Cfrac%7B%5Cpi%280.00205m%2F2%29%5E2%280.0004t%5E2-0.0001t%2B0.0004%29%7D%7B2.75%2A10%5E%7B-8%7D%5COmega.m%7D%5C%5C%5C%5CI%28t%29%3D4.75A)
hence, the current in the wire is 4.75A
1.) Law of Induction.
2.) Increase Winding Count
The firearm is unloaded.
The ramrod establishes whether the firearm is loaded or unloaded. It thrusts the bullet down the barrel. It is marked by wrapping some tape around it ( at the muzzle end ). This is to effectively signal if the muzzleloader is empty or loaded.