4.75 billion years ago, a large star near what is now the Solar System went supernova, sending heavy element debris outward into the galaxy. Some of the debris, after traveling long distances through space, collided with a Hydrogen cloud.
Answer:
12:3:1
Explanation:
<em>The typical F2 ratio in cases of dominant epistasis is 12:3:1.</em>
<u>The epistasis is a form of gene interaction in which an allele in one locus interacts with and modifies the effects of alleles in another locus</u>. There are different types of epistasis depending on the type of alleles that are interacting. These include:
- Dominant/simple epistasis: Here, a dominant allele on one locus suppresses the expression of both alleles on another locus irrespective of whether they are dominant or recessive. Instead of the Mendelian dihybrid F2 ratio of 9:3:3:1, what is obtained is 12:3:1. Examples of this type of gene interaction are found in seed coat color in barley, skin color in mice, etc.
- Other types of epistasis include <em>recessive epistasis (9:3:4), dominant inhibitory epistasis (13:3), duplicate recessive epistasis (9:7), duplicate dominant epistasis (15:1), and polymeric gene interaction (9:6:1).</em>
The cross between Dd egg-snail and a dd s snail mate will result in snails with genotype 1/2 Dd:1/2 dd and phenotype all right-coiling.
<h3>What is a genotype?</h3>
The genotype refers to the allele combinations that can be found for one or more loci in an individual.
The phenotype refers to how the genes and alleles interact to produce a physical trait in an organism.
In this case, one parent can produce two types of gametes (D and d), whereas the other parent can only produce d gametes.
Learn more about genotypes here:
brainly.com/question/22117
Although the DNA packaging with histones proteins is mean to form nucleosomes (groups of 8 histones proteins), the higher structures why the genetic material is packaged with those molecules is to form chromosomes, as you said.
