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>
<u>Answer:</u> C. A plant absorbing carbon dioxide during photosynthesis
<em>A plant absorbing carbon dioxide during photosynthesis can be considered as assimilation in the carbon cycle.
</em>
<u>Explanation:</u>
<em>The process of carbon fixation is called assimilation in carbon cycle. In the atmosphere carbon occurs in the form of carbon dioxide. </em>
By the process of carbon fixation this carbon dioxide is converted into carbon compounds and these act as source of energy in an ecosystem.
Photosynthesis is an example of carbon fixation process. Other processes like chemo-synthesis also fix carbon. <em>Majority of carbon fixation takes place in marine environments. </em>
Answer:
The 'gene' which causes (inherited, red and green types of) colour blindness is found only on the X chromosome. So, for a male to be colour blind the colour blindness 'gene' only has to appear on his X chromosome. For a female to be colour blind it must be present on both of her X chromosomes.
Explanation:
Sperm cells inside the pollen grain travel down the pollen tube and into the ovary which contains the ovules. Fertilization occurs when one of the sperm cells fuses with the egg inside of an ovule
Answer:
Both deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are made up of nucleotides which consist of three parts:TRUE
Explanation: