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>
More consumers than producers
Answer:
The correct option is A. The cell is sitting in a hypertonic solution.
Explanation:
A hypertonic solution is a solution in which there are more number of solutes present in the solution than inside the cell. The solutes then tend to pass into the cell through diffusion from the solution.
As it can be seen in the diagram, the concentration of salt is more in the solution i.e 40%. Hence, the salt from the solution enters into the cell by diffusion and has a concentration of 10% inside the cell which shows the cell to be placed in a hypertonic environment.
The answer is the option "c"
The eruptions are caused by an accumulation of gases that press under a volcano.
The molten rock continues to generate upward pressure but can not advanced; this causes that its force increases with the passage of time, since it continues accumulating hot gases trying to come to the surface.
Finally, the surface yields and a volcanic eruption occurs.
1. The lining up of chromosomes by the spindle fibers takes place at metaphase II phase. It is the second stage of meiosis II, the spindle draws the chromosomes towards the metaphase plate.
2. The formation of the nuclear envelope around each set of DNA takes place in telophase II. Along with the formation of the nuclear envelope, the process of cytokinesis also takes place in telophase II, producing four daughter cells, each comprising a haploid set of chromosomes.
3. The sister chromatids are pulled apart in anaphase II stage. In this phase, the sister chromatids are migrated towards the opposite poles of the cell with the help of protein fibers.
4. The centromeres are moved towards the poles of the cell at prophase II stage.
