terminologies Flashcards
1
Q
what is chromatin?
A
- it is a single DNA molecule coiled around histones to form an indistinct thread-like structure
2
Q
where can chromatin be observed in?
A
- a non-dividing cell
3
Q
what is a chromosome?
A
- a chromosome is highly condensed chromatin, becoming a distinct visible structure
4
Q
where can chromosomes be observed
A
5
Q
where can chromosomes be observed in?
A
- in a dividing cell
6
Q
what are sister chromatids?
A
- 2 chromatids joint together in a replicated chromosome
7
Q
how many DNA molecules make up 1 sister chromatid?
A
- 1 DNA molecule
8
Q
why are sister chromatids genetically identical?
A
- DNA is replicated during S phase of interphase
9
Q
what is a centromere?
A
it is the region where the 2 sister chromatids of a single replicated chromosome are joined
10
Q
what is the mitotic spindle?
A
- it is a structure that consists of fibres made up of microtubules & associated proteins
11
Q
what ability does the mitotic spindle have?
A
- it has the ability to lengthen or shorten by the polymerisation or depolymerisation of tubulin proteins
12
Q
what is a centrosome?
A
- it is called the microtubule organising centre in animal cells
- it is made up of a pair of centrioles
13
Q
what is the kinetochore?
A
- it is a disc-shaped protein structure that binds to the chromatids at the centromere
14
Q
how many kinetochores are there in a replicated chromosome?
A
2
15
Q
what is the function of the kinetochore?
A
- it is the location where the spindle fibres attach during nuclear division
