Chromosomal mutation

Question 1

Describe and explain chromosomal mutation

Answer 1

change in the chromosome number

Question 2

Process of Chromosomal mutation

Answer 2

Non-disjunction that could have happened at anaphase I or II
Failure of pair of homologous chromosomes 21 to separate to the opposite poles at anaphase I
OR Failure of sister chromatids of chromosome 21 to separate at anaphase II
Forms an abnormal gamete. Fusion of abnormal gamete with chromosomal number (n+1) and normal gamete with chromosomal number (n) results in an abnormal chromosome number in zygote (quote data)

Question 3

Mutations in meiosis vs mitosis

Answer 3

Mutation in cell with meiosis results in genetic variation of gametes that is passed on to offspring, but mutations in cell with mitosis only affects the same organism and is not passed on to future offspring.

Question 4

How to stop cancer reproduction

Answer 4

Vinblastin prevents spindle fibres formation, so chromosomes cannot be organised or removed, uneven distribution of chromosomes in daughter cells, failure to reproduce by mitosis

Question 5

Duplication, Inversion, Translocation, Deletion definition

Answer 5

Duplication. – repetition of a chromosomal segment.
Inversion. – A change in the direction of genetic material along a single chromosome.
Translocation.– A segment of one chromosome becomes attached to a nonhomologous chromosome
Deletion – Part of the chromosome is missing.

Question 6

totipotency>pluripotency>multipotency definition and example

Answer 6

totipotency (zygotic stem cells have the ability to differentiate into any cell type to form whole organisms),

> pluripotency (embryonic stem cells have the ability to differentiate into almost any cell type to form any organ)

> multipotency (blood stem cells have the ability to differentiate into a limited range of cell types).

Question 7

normal functions of stem cells in a living organism

Answer 7

Zygotic: (Totipotent)
Potential to give rise to all cell types and placental cells in an organism

Embryonic stem cells: (pluripotent)
Give rise to all specialised cells in the body

Perinatal (umbilical cord): (multipotent)
Differentiate into some types of cells

Adult stem cells: (multipotent)
Undifferentiated cells, give rise to a few related types of specialised cells.

Question 8

Cancer cells vs Stem cell

Answer 8

Both divide continuously, somatic cells, unspecialised cells, bypass apoptosis
Cancer bypass normal cell cycle controls, stem cell replicates under normal cell cycle controls
Cancer has mutation in DNA, stem cell does not have