Although the operation of natural selection requires that genotypes differ in fitness, for some geneticists it seems easier to understand natural selection than fitness. Partly this reflects the fact that the word “fitness” has been used to mean subtly different things. Here I distinguish among these meanings (e.g., individual versus absolute versus relative fitness) and explain how evolutionary geneticists use fitness to predict changes in the genetic composition
The phenotypic ratio obtained from a cross for only genetic trait, assuming it follows the simple mode of inheritance which is complete dominance, it would be 100% white cow, assuming roan bull is recessive.
Answer:
You gotta be more specific
Explanation:
or else i cant answer this question.
Answer:
1. Designing of the target vector.
2. Insertion of the target vector into the embryonic stem cell
3. Selection of the cells
4. Injecting selected cells into the new cells
5. Breeding of mouse with a normal mouse
Explanation:
The target vectors are made by inserting markers into them. The target vector is inserted into ES cells. The vector generally recombined with the target gene and knock-out that gene. Sometimes, recombination of vectors occurs at incorrect place.
The cells survive in the presence of markers only if the target gene is incorporated with target vector. The cells with the target vector are injected into a normal developing embryo of mouse.
The developed mouse will consist of heterozygous knockout cells and its own cells. The normal mouse is bred with this chimeric mouse. The offspring of these mouse are able to transfer knock-out gene to next generation.