GENETIC & Molecular BIOLOGY - Essay Example

The female horse has 64 diploid chromosomes and 32 chromosomes in her haploid gametes. This results in two gametes, male (31 haploids) + female (32 haploids) equals 63 diploid chromosomes in the offspring. It is important to note that the mule (generation 1 hybrid offspring of horse and ass) is not able to produce offspring. The reason for this is that the horse has 18 acrocentric autosomes while the ass has 11. This vast difference in number of acrocentric and met centric chromosomes causes a synapsis in of homologues during prophase 1 of meiosis, rendering the mule species infertile and sterile as no viable gametes can be formed. (b) This particular diagram is representative of interphase G2 (right before prophase takes place) of mitosis.

This diagram shows the newly developed centrioles, and the beginning of spindle fibers. It also shows the chromosomes just beginning to line up. ( c) This diagram illustrates telophase of mitosis as it shows the beginning of cytokinesis resulting in two daughter cells. The chromosomes are also moving to opposite poles within their respective daughter cells. (1.8) The number of different gametic chromosomal combinations possible in the garden pea (male versus female) where 2n = 14 is . When n=7, one can find the number of possible combinations by using the formula 2^n or in this case 2^7, which is equal to 128.

Thus, there are 128 possible different gametic chromosomal combinations in the garden pea. (1.12) In humans, there are 46 pairs of homologous chromosomes. In a human secondary spermatocyte, there are 23 chromosomes. Also in humans, spermatotids contain 23 chromosomes, spermatozoa contain 23 chromosomes and spermatagonia contain 46 chromosomes. (1.14) When looking at corn, we see that corn has a diploid number of 20 and thus a haploid number of 10 or 2n=20( as corn has diploid cells). The first meiotic product would result in a haploid cell with 10