A myelinated axon has a sheath around it and a bore axon doesn't have it, it's open or exposed so to speak. T<span>he myelin is made up of fat and protein and works like insulation. these axons make up the white matter in the brain since it appears white. The sheath helps to keep the electrical current from leaving the axon and the myelin sheath provides a tract along which regrowth can occur. </span>
The correct answer is letter C, in most primates, the inability to move the ear has been replaced by the ability to stand upright on two legs. This is because movement was much of a need to these primates than hunting for food. They needed to be agile to locate specific places where sources of food are abundant.
the answer is the trophic level
<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
A. Indique la relación entre la ocurrencia de cancer y la edad.
