Lab 4 - Genetics

Question 1

Phenotype

Answer 1

An organism’s appearance or observable trait. The biochemical characteristics of an organism. Example: Left Handed people are (LL) Right handed people are (LR or RR). There are 3 genotypes but only 2 (word)

Question 2

Genotype

Answer 2

The genetic make up of an organism. Comprised of a set of alleles.

Question 3

Recessive Allele

Answer 3

When two alleles differ, this allele has no effect on F_1 appearance.

Question 4

Homozygous/Homozygote

Answer 4

When two paired alleles have identical phenotype.

Question 5

Dominant Allele

Answer 5

The allele that determines appearance in a heterozygous pair.

Question 6

Heterozygous/Hetrozygote

Answer 6

The pairing of alleles with two different phenotypes.

Question 7

Gametes

Answer 7

A male or female cell with the haploid number of chromosomes. Pairs with the matching gamete of the opposite gender to form a diploid cell.

Question 8

Locus (Plural: Loci)

Answer 8

The position of a gene (or a mutation) on a chromosome

Question 9

Diploid

Answer 9

The cell containing the 2n amount of chromosomes n from each parent.

Question 10

Crossed

Answer 10

Offspring that carries the genetic material of each parent.

Question 11

F_1 Generation

Answer 11

The generation that immediately follow the P (parent) generation.

Question 12

True breeding

Answer 12

Certainty that over many generations, only one trait is present in both parents. (Purple flowers which produce purple flowers 100% of the time would be the ideal P generation for true breeding)

Question 13

Hybrid/Hybridization

Answer 13

The creation of an F_1 generation from true breeding Parents in the P generation.

Question 14

F_2 Generation

Answer 14

The generation following the F_1 generation. If there are recessive alleles in both parents, a small ratio of offspring will have the recessive traits.

Question 15

Punnet Square

Answer 15

A grid used to visually demonstrate the probability of a genotype resulting from the possible phenotypes.

Question 16

Monohybrid Cross

Answer 16

When only a single trait is being observed in the heterozygous offspring.

Question 17

Dihybrid Cross

Answer 17

The P generation differs in 2 traits. The F_2 generation will produce ratios near 9:3:3:1

Question 18

Law of Independent Assortment

Answer 18

Mendel’s law stating that alleles sort independently of each other. An allele one gamete receives for a gene will not affect the allele received for another gene.

Question 19

Allele

Answer 19

One of two or more alternatives found on the same locus of a gene

Question 20

Evolution

Answer 20

A change in the frequency of alleles.

Question 21

Genetic Drift

Answer 21

A change in the frequency of an allele due to chance

Question 22

Natural Selection

Answer 22

Greater than average reproduction as a result of having a particular trait