A 2 3 4 B a

A prairie grass species called "little bluestem" is tetraploid. It has four complete sets of chromosomes. There are ten kinds of chromosomes; in other words, each complete set of chromosomes has a total of 10 chromosomes. A single somatic cell (e.g., a cell in a leaf) will have 40 chromosomes, 4 of each kind of chromsome, i.e., 4 of the number 1 chromsome, 4 of the number 2 chromsome, etc.  The illustration below shows prophase of meiosis 1 in chromosome number 10. In a diploid cell, there would be one tetrad (group of 4 chromatids) for each kind of chromosome.  For example, there would be one tetrad for chromosome 8, one for chromsome 9, etc.  When the tetraploid little bluestem undergoes meiosis, how many of chromosome number 10 will each sperm cell carry?

In a turtle species, a diploid cell in the G1 phase of the cell cycle contains 22 picograms of DNA (picogram is a measure of the total mass of the DNA present). How much DNA is present in a cell of the same species at prophase II of meiosis (prophase of the second meiotic division)?

Cat fur coat color genetics is interesting. Orange fur is dominant (''B'') to black fur (''b'') and piebald, which is white spotting, is dominant (''S'') to non-white-spotted (''s''). Both of those genes are located on the X chromosome. In addition, in cats, somatic cells exhibit X-inactivation randomly, which explains why there are tortoiseshell cats (when heterozygous, have orange and black spots) as well as calico cats (orange and black but also with white spots). An orange and white spotted male is mated with a tortoiseshell female. State the genotype of the male and the female.

For an organism with 3 pairs of chromosomes (6 total chromosomes, 2n = 6), draw chromosome diagrams for the following phases of meiosis: prophase I, metaphase I, anaphase I, telophase I, prophase II, metaphase II, anaphase II & telophase II. Be sure to draw the correct number of chromosomes and the correct number of chromatids per chromosome. Use a different color to represent each chromosome type (for example, use blue to indicate all copies of chromosome 1, red for all copies of chromosome 2, and green for all copies of chromosome 3).

In fruit flies, chromosomal crossing over does not occur in meiosis in males, whereas crossing over does occur in meiosis in females. In fruit flies that are heterozygous at many genes (i.e. many maternal and paternal versions of the genes differ), at what stage would cells no longer be heterozygous for any gene during the process of meiosis? a)After the second meiotic division in males, and after the first meiotic division in females. b)After the second meiotic division in both males and females. c)After the first meiotic division in both males and females. d)After the first meiotic division in males, and after the second meiotic division in females.

During metaphase I of meiosis, tetrads align along the metaphase plate independently of each other. Therefore, there is a random “shuffle” of maternal and paternal chromosomes in the resulting gametes.The following diagram demonstrates how this works in a diploid cell with four chromosomes . Because there are two pairs of chromosomes and each pair can align in one of two ways during metaphase I, the number of possible variations in the gametes produced is , or .For an organism that is , there are three pairs of chromosomes, so the number of possible variations in the gametes produced due to independent assortment in metaphase I is , or . In an organism with a haploid number of , how many possible combinations of maternal and paternal chromosomes can occur in its gametes? Select one: a. 72=49 b. 27=128 c.17=1 d. 214=16 384

Assume that diploid plant A has a cytoplasm genetically different from that of plant B. To study nuclear–cytoplasmic relations, you wish to obtain a plant with thecytoplasm of plant A and the nuclear genome predominantly of plant B. How would you go about producingsuch a plant?

Assume that the diploid number of a certain species is four chromosomes, two large and two small (2n=4). a)  Of the following figures, which represents a 3n (triploid) cell in mitotic metaphase? b)  For each of the wrong answers from part (a) above, explain briefly why it cannot represent a triploid cell in mitotic metaphase.