Explanation:
As I think vector is the correct one.
Answer:
Convergent Evolution.
Explanation:
When two different species that are very distantly related but have similar traits its Convergent Evolution due to environmental pressures.
The correct answer is d. morula.
<span>
A morula is a stage in early development, formed 3–4 days after fertilization. It is a 16-cell mass which forms a solid ball contained within the zona pellucida. A morula develops into a blastocyst.</span>
I believe he is looking for an allele
An allele is a variant form of a gene. Some genes have a variety of different forms, which are located at the same position, or genetic locus, on a chromosomes. Humans are called diploid organisms because they have two alleles at each genetic locus, with one allele inherited from each parent.
SHELL products are derived from invertebrates.
