Mutations

Question 1

Mutations

Answer 1

Changes in the DNA bases or chromosones - change protien produced

Question 2

Factors that cause mutations

Answer 2

environment: low O2, change in food
chemicals: lead, asbestos
radiation: UV, x-rays

Question 3

Germ Line

Answer 3

sperm and eggs genes are changed

- passed onto future generations

Question 4

Somatic

Answer 4

all other cells in the body

- not passed on to offspring

Question 5

Gene mutations

Answer 5

Change in DNA bases - affects protiens

Question 6

Point mutation

Answer 6

change a single nucleotide
eg. substitution: change a single letter
inversion; switches position of letters

Question 7

Frameshift mutations

Answer 7

additions or deletions of nucleotides
eg. insertion; extra letters are added
deletion; letters are removed

Question 8

Gene mutations can cause

Answer 8

Silent - no change to protein
Positive variation
negative variation
- genetic disease 
eg. cystic fibrosis, Tay-Sachs

Question 9

Chromosome mutations

Answer 9

one whole chromosome is missing or an extra chromosome

• large section of DNA is missing or added or moved to wrong place
  eg. 2n=46 -> 2n=45 or 47

Question 10

When do chromosome mutations occur:

Answer 10

cells go through mitosis or meiosis from crossing over or homologous separating

• many genes are affected
• nondisjunction: pair of homologous chromosomes failed to separate at anaphase
• • both chromosomes in pair pass to same daughter cell

Question 11

Karyotype

Answer 11

Individuals collection of chromosomes

• picture of all aprox. 46 chromosomes in one cell
  shows: size, bonding patterns, centriole location

Question 12

What do karyotypes do?

Answer 12

used to look for abnormal numbers of structures of chromosomes
pairs 46 chromosomes to create 23 pairs
- discovers abnormal chromosome numbers
eg. Down Syndrom - extra no. 21 chromosome

Question 13

Female chromosomes

Answer 13

XX chromosomes