Lab 4 - Genetics Flashcards
(22 cards)
Phenotype
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)
Genotype
The genetic make up of an organism. Comprised of a set of alleles.
Recessive Allele
When two alleles differ, this allele has no effect on F_1 appearance.
Homozygous/Homozygote
When two paired alleles have identical phenotype.
Dominant Allele
The allele that determines appearance in a heterozygous pair.
Heterozygous/Hetrozygote
The pairing of alleles with two different phenotypes.
Gametes
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.
Locus (Plural: Loci)
The position of a gene (or a mutation) on a chromosome
Diploid
The cell containing the 2n amount of chromosomes n from each parent.
Crossed
Offspring that carries the genetic material of each parent.
F_1 Generation
The generation that immediately follow the P (parent) generation.
True breeding
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)
Hybrid/Hybridization
The creation of an F_1 generation from true breeding Parents in the P generation.
F_2 Generation
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.
Punnet Square
A grid used to visually demonstrate the probability of a genotype resulting from the possible phenotypes.
Monohybrid Cross
When only a single trait is being observed in the heterozygous offspring.
Dihybrid Cross
The P generation differs in 2 traits. The F_2 generation will produce ratios near 9:3:3:1
Law of Independent Assortment
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.
Allele
One of two or more alternatives found on the same locus of a gene
Evolution
A change in the frequency of alleles.
Genetic Drift
A change in the frequency of an allele due to chance
Natural Selection
Greater than average reproduction as a result of having a particular trait
