Exam 1 Definitions

Question 1

Evolution (Pop Gen) Definition

Answer 1

changes in the genetic composition of a population

Question 2

Evolution (Hist Geol) Definition

Answer 2

The origin of new forms of life by descent from pre-existing forms

Question 3

Microevolution Definition

Answer 3

Changes in the genetic composition of a population

Question 4

Macroevolution Definition

Answer 4

The origin of new grades

Question 5

Grade Definition

Answer 5

a group of organisms with characteristics and abilities that are not found in other groups

Question 6

Example of Macroevolutoin

Answer 6

The origin of photosynthesis and the origin of mammals

Question 7

Genotype frequency definition

Answer 7

What fraction of individuals have a specific genotype

Question 8

Genotype Frequency Formula

Answer 8

Question 9

Gene\Allele frequency definition

Answer 9

What fraction of the copies of a gene are a specific allele

Question 10

Gene Definition

Answer 10

A portion of a DNA molecule associated with a specific function

Or

A portion of a DNA molecule that codes for a product

Question 11

Allele Definition

Answer 11

Alternative form of the same gene

Question 12

Gene/Allele Frequency Formula 1

Answer 12

Question 13

Gene/Allele Frequency Formula 2

Answer 13

Question 14

There must be _____________ in a population in order tohave evolution

Answer 14

genetic variation

Question 15

Name three ways genetic variation can be added to population

Answer 15

• Mutation (= changes in the hereditary materials [DNA andchromosomes]: for example, allele A → allele a)
• Recombination (formation of new combinations of existingalleles and genotypes: for example, AA x aa → Aa)
• Migration (individuals with new [to the population] alleles or genotypes may migrate into the population)

Question 16

Gene/point mutations definition

Answer 16

Mutations that involve only a few DNA nucleotides and cannot be detected with light microscopy

Question 17

Chromosome mutations (chromosome aberrations) definition

Answer 17

Mutations that involve larger segments of DNA and can (often) be detected with light microscopy. Chromosome mutations may change the number of chromosome in a cell, the size of chromosomes, or the order of genes on a chromosome

Question 18

Name the two main types of gene mutations

Answer 18

Substitutions

Insertions and Deletions

Question 19

Substitutions Definition

Answer 19

One base replaces another base in the DNA chain

Example: TAC → CAC

Question 20

Define Insertions and deletions

Answer 20

one or more nucleotides are added to (or deleted from) the DNA chain

Example: TACTACTAC… → TACGTACTAC…

Question 21

Name two types of substitutions

Answer 21

Transitions

Transversions

Question 22

Define Transitions

Answer 22

a purine base (adenine or guanine) replaces another purine base or a pyrimidine base (thymine or cytosine) replaces another pyrimidine base
Example: TAC → TGC

Question 23

Define Transversions

Answer 23

a purine base replaces a pyrimidine base or a pyrimidine base replaces a purine base
Example: TAC → TCC