Chromosomes

Question 1

what is the purpose of a chromosome

Answer 1

to efficiently package long strands of DNA to be stored between divisions, and moved during divisions

Question 2

histones

Answer 2

Histones are the proteins around which the DNA helix is wrapped when condensed into chromosomes

Question 3

nucleosomes

Answer 3

A nucleosome is a set of 8 histone proteins in a cube shape with DNA coiled around it much like thread around a spool. There is further coiling and supercoiling of the nucleosomes to create the final condensed chromosome

Question 4

chromatin

Answer 4

Chromatin is a general term for DNA + protein. Therefore, chromosomes are made up of chromatin.

Question 5

diploid

Answer 5

A diploid cell has 2n chromosomes. Diploid cells have two copies of each chromosome

Question 6

haploid

Answer 6

a haploid cell has n chromosomes. haploid cells have only one copy of each chromosome

Question 7

homologues

Answer 7

Homologues are two related but non-identical chromosomes—one originating from each parent.

Question 8

sister chromatids

Answer 8

Sister chromatids are the two strands of DNA in a duplicated chromosome attached by a centromere. Assuming no mutations or errors in replication, they are identical as long as crossing over has not occurred.

Question 9

centromere

Answer 9

The centromere is the region of the chromosome that joins the two sister chromatids.

Question 10

kinetochore

Answer 10

The term kinetochore is often used synonymously with centromere, but they are not identical. The centromere is a region on the chromosome and the kinetochore is a specialized group of proteins to which the spindle fibers attach directly during mitosis/meiosis.

Question 11

Where is DNA found in the cell

Answer 11

Nuclear DNA is found in the nucleus and never leaves the nucleus. However, mitochondria also contain DNA—although it is their own unique-lineage circular DNA, NOT nuclear DNA.