Answer:
Clues that can be used to determine whether the movement of solutes through the membrane is passive or active could be the molecule size, membrane potential, and the presence/absence of membrane protein.
Explanation:
Solutes transport through the cellular membrane depends on the solute size, membrane potential, and the presence/absence of integral membrane protein.
There are two types of transport: Active and passive.
- Passive transport: It does <u>not need energy</u>; it is driven by a chemical potential gradient. <u>Small molecules</u> with no charge are transported through the membrane in a gradient favor, from a high concentration region to a low concentration region. There are two types of passive transport: <em>By simple diffusion</em> (small molecules pass through the membrane by themselves) and by <em>facilitated diffusion</em> (molecules are helped by integral membrane proteins to pass through the membrane). In facilitated diffusion, the helping protein can be a <u>channel protein</u> (hydrophilic pores that allow the molecule to pass with no interaction) or a <u>carrier protein</u> (proteins with mobile parts that suffer modification as the molecule pass to the other side).
- Active transport: It <u>does need ATP energy</u> to pass the molecule through the membrane, as they have to <u>move against the electrochemical gradient</u>. This kind of transport is always mediated by a <u>carrier protein</u>. These proteins join with the molecules and suffer changes as they pass the solute to the other side of the membrane. An important example of this kind of transport is the sodium-potassium bomb.
The lac operon, which stands for Lactose operon is known as an inducible system. It is the an operon required for the transport and metabolism of lactose some enteric bacteria (Echerichia coli for example). The Lac operon is only activated in the presence of a key molecule. The key molecule is lactose.
From the given options the following best describes the Lac operon:
D. The repressor is freed from the operator when lactose is present.
Explanation:
In digestion, the liver is involved in processing the nutrients that are absorbed from the small intestine. It helps in the digestion of fat.
On the other hand, the liver maintains homeostasis by serving an important function in the excretory system.
<span>The nurse should give the highest priority care to the Ventricular Arrhythmias Patient. Because Ventricular arrhythmias start in the heart's lower chambers, the ventricles. They can be very dangerous and usually require medical care right away. Ventricular arrhythmias include ventricular tachycardia and ventricular fibrillation.
Ventricular tachycardia is an abnormal electrical impulses that start in the ventricles and cause an abnormally fast heartbeat. This often happens if the heart has a scar from a previous heart attack. Usually, the ventricle will contract more than 200 times a minute.
Ventricular fibrillation is an irregular heart rhythm consisting of very rapid, uncoordinated fluttering contractions of the ventricles.The ventricles do not pump blood properly, they simply quiver. Ventricular fibrillation is life threatening and usually associated with heart disease. It is often triggered by a heart attack.</span>
