Answer:
D
Explanation:
Prokaryotic are simple cells and do not have nucleus.
<span>My pea plant has an unknown genotype for flowers, whether it has two dominant traits for white flowers (WW) or one dominant and one recessive (Ww) leading to white flowers; therefore I am doing a testcross in order to determine the genotype of my pea plant. The best plant to do this with is one that has a phenotype of purple flowers (ww) - that is, it is homozygous for the recessive trait.
If I use a homozygous recessive plant, I know exactly what its genotype is. I don't have to worry about whether it's got one or two dominant alleles; I know that at least half of my alleles are going to be the recessive w.
This makes identifying the offspring's genotype very simple. If I find that the offspring have at least some purple flowers among them, I know that my original plant had to be Ww; that is it had to have one dominant and one recessive allele for the flower color gene. If, however, all of the offspring are white flowers, I know that my original pea plant had both dominant alleles (WW).</span>
<h2>Sea star </h2>
Explanation:
In the given example sea star played the role of keystone species
- Robert Paine actually coined the term keystone species to describe the effect that the sea stars had on biodiversity in this community
- Keystone species are those species which are least abundant but play a governing role to decide the structure and function of community
- Loss of keystone species in a community can lead to disturbance in structure and function of a community and it cannot be recovered by other species
Answer:
Diffusion
Explanation:
Diffusion is the spontaneous movement of gases, without the use of any energy or effort by the body, between the alveoli and the capillaries in the lungs.
Within any ecosystem, there is a fixed amount of energy available for
organisms to use. since organisms usually produce more offspring than a
given
ecosystem can support, this causes competition. They compete over who will be the dominant one and who will be left to die.