When it comes to population evolution and genetics, we cannot fail to cite the Hardy-Weinberg principle which emphasizes that if evolutionary factors such as natural selection, mutation, migration and genetic oscillation do not act on a particular population, the frequencies genotypic proportions will remain constant.
The five requirements for a population to be in Hardy-Weinberg equilibrium are:
- Large-scale breeding population: For a population to be in Hardy-Weinberg equilibrium, it is important that this population is large, as small populations favor genetic drift (unanticipated fluctuations in allele frequencies from one generation to another).
- Random mating: In order for the Hardy-Weinberg equilibrium to occur, it is necessary that the mating occur at random, with no preference for certain groups within the population. In this case, we say that the population is in panmixia, that is, they all mate at random.
- No mutations: Mutations alter the total alleles present in a population (gene pool). Therefore, in a Hardy-Weinberg equilibrium population, no mutations should occur.
- No gene flow: When there is gene flow due to migration or immigration of individuals, some genes may be included or excluded from the population. Thus, in an equilibrium situation, no gene flow occurs.
- Lack of natural selection: For a population to be in Hardy-Weinberg equilibrium, natural selection must not be acting on it. If natural selection acts, some genotypes will be selected, modifying the allelic frequencies of the population.
Drosophila melanogaster an excellent model for studying fundamentals of development because many of the genes involved in the development of the fruit fly are also found in humans and the precise formation of each of their 959 body cells has been mapped.
Its many of the genes involved in the development of the fruit fly are also found in humans. Drosophila melanogasteris which is also called Fruit fly is small in size and minimal requirements, many fly's can be raised and tested within a small laboratory which does not have access time, space or funding.
Genetic factors also make this fly an ideal model organism. Drosophila melanogasteris only has four pairs of chromosomes compared to 23 pairs in humans.
To learn more about Drosophila melanogaster here
brainly.com/question/18763357
#SPJ4
A more clear understanding of the world around us.
They dont release any oil
they "preen" their feathers with their beaks not put oil on them
Answer:
Cells divide twice
Explanation:
Meiosis may be defined as the process of cell division in which a single cell divides to give four daughter cells and each daughter cells have half number of chromosomes.
Meiosis is also known as reduction division as the chromosome number reduces upto half in the progeny cells as compared with the parent cell. The cells divide twice in meiosis and give rise to four daughter cells.
Thus, the correct answer is option (4).