The correct answer is color vision.
The macula lutea is an area near the center of the human's eye retina. It has an oval shape and is responsible for the high-resolution color vision we have under good light conditions. If the macula lutea is destroyed, due to macular degeneration or a retinal detachment, then this color vision is impaired.
Answer: B. The number of individuals that a habitat can sustain with the resources that it has available.
Explanation:
A carrying capacity is the number of individuals of the population belonging to a particular species that an habitat or region or ecosystem can support or sustain in terms of providing the resources. If the population exceeds over the carrying capacity then this results in decline in members of the population.
According to the above description the accurate definition of carrying capacity is B.
Answer:
a. the virus must be able to cross-link red blood cells directly.
Explanation:
Viral hemagglutination assay is a method which is used for the quantification of the relative concentration of the viruses.
The principle on which the hemagglutination assay works is as follows:
- There are sialic acid receptors present on the surface of the red blood cells which will bind to the haemagglutinin glycoprotein present on the surface of the viral particle.
- Due to the binding of the sialic acid receptors with haemagglutinin particle there will be cross-linking of the red blood cells by the viral particles and a lattice formation will take place.
- The lattice will remain suspended in the solution however if the concentration of the virus particles will be less, the lattice will settle down in the well.
Thus, this method allows knowing the relative concentration of the virus.
<em>Due to its basic principle of cross-linking this method works well for only a few viruses such as influenza virus. </em>