chapter 4: significance of genetic variation

Question 1

where does heritable variation come from

Answer 1

-mutation
-independent assortment
-recombination

Question 2

mutation

Answer 2

-stable change in DNA sequence
-rate depends on environment, gene, and type of mutation
-partially predictable variation
-can have neutral, deleterious, or beneficial effects on fitness (not directed toward an outcome)

Question 3

types of mutations

Answer 3

-point
ATGCAGT - ATCCAGT
-insertion/deletions
ATGCAGT - ATGGCAGT
-changes in repetition
ATGATGATG - ATGATGATGATG
-chromosomal rearrangements
ATGCAGT - TGACGTA

Question 4

independent assortment

Answer 4

-different combinations of chromosomes that occur during meiosis

Question 5

recombination

Answer 5

-when two molecules of DNA exchange pieces of genetic material with each other
-homologous chromosomes swap DNA segments in meiosis

Question 6

preformationism

Answer 6

-previous belief that only one parent contributed to inheritance
-spermists vs ovists

Question 7

theory of blending inheritance

Answer 7

-previous belief that offspring have a mix of the characteristics of their parents
-irreversible blend of traits