Answer: The statement is false
Explanation:
A community refers to a group of plants and animals that occupy a given area and can adapt to the conditions of their environment. Hence, community include biotic factors (living organisms) and abiotic factors (non-living factors like soil, weather etc).
Thus, the statement is false
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>
<span>d. neither of these will cross a plasma membrane.
Glucose cannot diffuse across a plasma membrane as it is polar. Since the question doesn't specify the type of diffusion, simple diffusion is assumed.
If you count facilitated diffusion, then A is the answer.</span>
<span>1.keeps tooth alive
</span><span>pulp
2.surface of teeth
enamel
3.tube carrying food to stomach
esophagus
4.last major organ in digestive system
large intestine
5.digestive organ located above waist, close to ribs
stomach
6.first stage of digestion takes place here
mouth
7.regular squeezing movements
peristatiss
8.blood vessel leading from heart
artery
9. windpipe
trachea</span>
