Chapter 15 - Genetics

Question 1

Probability of crossing over is dependent on the position on the chromosome, how

Answer 1

the further apart traits are on a chromosome the more likely they are to cross over and sort independently

Question 2

Define:
Point mutation
Deletion
Inversion
Translocation
Frame shift

Answer 2

Point mutation: affects a single base pair
deletion: removal of a DNA sequence
Inversion: reversal of a segment
Translocation: 1 chromosome breaks an attaches to another
Frame shift: when changes aren’t made in multiples of 3

Question 3

How is DNA cloned?

Answer 3

DNA is cloned using bacterial plasmids that then replicate through normal life cycle of DNA
plasmid = DNA molecule

Question 4

What kind of bonds elongate DNA molecule to add a foreign molecule in?

Answer 4

Phosphodiester bonds

Question 5

How do positive and negative selection detect mutants?

Answer 5

Positive selection rejects non-mutated (normal) therefore nothing grows. Negative selection grows both wild type and mutant so negative can isolate.

Question 6

What’s unique about bacteria?

Answer 6

Bacteria have cell walls like fungi

Bacteria are small cells and reproduce exponentially

Question 7

What does metaphase 1 of meiosis facilitate

Answer 7

Metaphase 1 of meiosis facilitates segregation, recombination and independent assortment of genes
*mutations occur randomly at all phases of cell cycle

Question 8

The frequency of Huntingtons (dominant) is 0.6. What is the percentage of people free of the disease?

Answer 8

Frequency is 0.4 but frequency of homozygous recessive genotype q^2 = 0.4^2 = 0.16