Answer:
by testcrossing with a homozygous recessive partner
Explanation:
<u>If a pet cockroach exists whose zygosity is unknown, this can be determined by a test cross. A test cross involves crossing an organisms whose zygosity is unknown with a partner that is homozygous recessive for the same trait.</u>
Let us assume that brown body is represented by the allele B, the dominant allele. The homozygous recessive version would be bb.
The genotype of a brown cockroach whose zygosity is not known can be denoted as B_, where '_' can be a 'B' or a 'b'.
When B_ is crossed with bb:
B_ x bb
Progeny
2 Bb
2 _b
The phenotype of Bb would be brown (since B is dominant over b) while the phenotype of _b would depend on the zygosity level of the cockroach.
If the unknown genotype is BB, then _b becomes Bb and the phenotype will be a brown body. This means that all the progeny will appear brown. (<em>see the first attached image for the Punnet's square</em>)
In other word, if the unknown genotype is bb, then _b becomes bb and the phenotype will be a alternate color (non-brown) body. This means that 50% of the progeny will appear brown while the remaining 50% will be in the alternate color. (<em>attached</em>
Step 1:
The bacterium cell must copy its DNA so the new cells will have DNA. DNA or, deoxyribonucleic acid, has all of the information the bacterium will need to survive, so it is important it gets copied. The DNA is tightly wound so it is in a neat package called a chromosome.
Steps 2 and 3:
The bacterium now grows larger. This allows for some separation between the two DNA copies that are inside the cell. A division develops in the middle of the bacterium. This division eventually completely divides the bacterium in half. This is called cytokinesis.
Step 4:
Each cell is now called a daughter cell and they separate.
The steps of binary fission
binary fission
Binary fission results in two identical daughter cells. This is a type of asexual reproduction, or creating genetically identical offspring. If humans were able to reproduce using binary fission, it would look something like this: your mother or father would grow larger, and inside all of his or her DNA would be copied. Eventually your parent would split in half creating an identical clone.
It is a mode of natural selection where an extreme phenotype is favored by the other phenotypes causing the allele frequency to shift over time in the direction of that phenotype