Question

A diploid cell contains three pairs of homologous chromosomes designated C1 and C2, M1 and M2, and S1 and S2. No crossing over occurs. a. What combinations of chromosomes are possible in daughter cells following mitosis? b. What combinations of chromosomes are possible in cells undergoing the first meiotic metaphase? c. What combinations of chromosomes are possible in haploid cells following both divisions of meiosis?

Answer 1

in mitosis the chromosome no is retained so u get all C1C2M1M2S1S2
In first meiotic metaphase u have homologous paired aligned on the equator...so u would have again all chromosomes.
in the haploid cells u have half d original no of chromosomes. so the combinations could be
c1m1s1 and c2m2s2
c1m1s2 and c2m2s1
c1m2m2and c2m1s1

Answer 2

are u expectin dis kind of ans?

Answer 3

this is good, but I would like you to explain more as to why. Just so that I know clearly why this is the case

Answer 4

ok sure.
u know what is mitosis and meiosis?

Answer 5

i'm a little rusty on that part

Answer 6

ok...Mitosis is the process by which a cell, which has previously replicated each of its chromosomes, separates the chromosomes in its cell nucleus into two identical sets of chromosomes, each set in its own new nucleus. It is a form of nuclear division.
Meiosis Listeni/maɪˈoʊsɨs/ is a special type of cell division necessary for sexual reproduction in eukaryotes. The cells produced by meiosis are gametes or spores. In many organisms, including all animals and land plants (but not some other groups such as fungi), gametes are called sperm and egg cells.

Answer 7

i searched for this on this same site n i found this answer

a) In mitosis, two genetically identical daughter cells are produced. Thus, the only possible combination of chromosomes is C1/C2/M1/M2/S1/S2 since all genetic material is inherited.
b) The first meiotic division serves to split homologous pairs into two different cells, which are now haploid. There are 8 possible combinations of chromosomes (2 chromosomes for each homologous pair). For instance, a cell at this stage could inherit C1/M1/S1, or C2/M1/S1, or C1/M2/S1, etc.
c) The same 8 combinations as above. The second meiotic division splits double-stranded chromosomes of each of these haploid cells into two daughter cells each so that only single-stranded chromosomes remain. Since no crossing over occurs, the two cells descended from each haploid cell will be genetically identical to the cell it came from. For instance, if the first meiotic division produces a cell with the combination C1/M1/S1, the second meiotic division of this cell will produce two more cells with the combination C1/M1/S1. The difference is that the end of meiosis I produces cells with double-stranded chromosomes, while the end of meiosis II produces cells with single-stranded chromosomes.

Answer 8

so the conclusion from this is in mitosis the chromosomal no is maintained while in meiosis it is halved.

Answer 9

with me so far?

Answer 10

keep going :)

Answer 11

so i ur 1st ques all the chromosomes should be present in a cell...rite?

Answer 12

all the chromosomes are in a cell , but when it in the daughter cell"S" shouldnt it be double?
cause there 2 or more?