<h2>Urea </h2>
Explanation:
Urea is a small nitrogenous compound which is the main end product of protein catabolism in mammals
- Urea is a nitrogen-containing substance normally cleared from the blood by the kidney into the urine
- It is made predominantly in the liver from ammonia and bicarbonate and is one of the main components of urine
- The rate of synthesis varies from 300 to 600 mmol/day depending on the protein intake
- All of this urea eventually finds its way into the urine
- Because urea makes up a large part of the obligatory solute excretion, its osmotic pressure requires significant volumes of water to carry the urea
- Urea passively crosses biological membranes, but its permeability is low because of its low solubility in the lipid bilayer
- Some cells speed up this process through urea transporters, which move urea by facilitated diffusion
- Urea is passively reabsorbed in the proximal tubule, but its route of transport is not clear
- Urea transporters have not yet been identified for the proximal tubule
I think the correct answer from the choices listed above is option A. One way in which bacteria differs from humans is that bac<span>teria are single-celled while humans contains a lot of cells. Bacteria can be found microscopically while humans are not. Hope this answers the question.</span>
Answer:
B. Antibodies react specifically with an antigen.
Explanation:
Serological tests are blood tests that look for antibodies in your blood. They can involve a number of laboratory techniques. Flucculation tests are based on the precipitation that takes place when antibody and specially prepared antigens are mixed together
Answer:
Explanation:A mechanical wave requires an initial energy input. Once this initial energy is added, the wave travels through the medium until all its energy is transferred. In contrast, electromagnetic waves require no medium, but can still travel through one.
The first was that all organisms have descended with modification from common ancestors.
The second was that the major agent of modification is natural selection acting on variation between individuals.
