Answer: For three traits inherited in a dominant/recessive pattern, the probability of an offspring in a trihybrid cross between parents heterozygous for all three traits to be recessive at exactly two of the three loci is 23/64.
Explanation: Let A, B and C represent the dominant alleles and a, b and c represent the recessive alleles. The genotype of each of the parent will be AaBbCc since it has been said to be heterozygous for all the three traits. There are eight (8) possible different types of gametes from each of the genotype. This can be calculated using 2^n where n is the number of heterozygous loci.
The number of heterozygous loci in the genotype AaBbCc is three (3). 2^3 = 8. The gametes are;
ABC
ABc
AbC
Abc
aBC
aBc
abC and
abc.
Therefore, sixty-four possible offsprings are expected from the cross AaBbCc x AaBbCc.
Out of these offsprings, twenty-three (23) are expected to be heterozygous at two loci as boldly shown in the attached image.
This looks like mitosis where chromosomes split up and duplicate
Answer:
Earliest- gametophyte dominance, sporophyte dependence
Middle- sporophyte dominance, gametophyte independence
Recent- sporophyte dominance, gametophyte dependence
Explanation:
The life cycle of plant alternates between the two phases: the haploid gametophyte which produces gametes and the diploid sporophyte which produces spores. The evolution of land plants shows how these are dependent on each other in terms of the requirement of nutrition.
In bryophytes, the gametophyte is the dominant phase on which the sporophyte depended. Later in pteridophytes, the sporophyte became dominant which is present in the later evolved groups namely the gymnosperms and the angiosperms. The gametophyte was independent on the sporophyte but in angiosperms and gymnosperms, it is dependent.
Answer:
cellulose present in cell wall of dead sclerenchyma is the wood that we use in furniture in home
Option C Habitat.... Polar bears are only found in the Arctic. The most important habitats for polar bears are the edges of pack ice where currents and wind interact, forming a continually melting and refreezing matrix of ice patches and leads (open spaces in the ocean between sea ice).