Lecture 4 - Genetics And Mendel Flashcards
Who is Gregor Mendel?
Augustian friar known for founding the science of genetics.
Mendel conducted experiments on pea plants.
What are the three generations in Mendelian genetics?
Parent generation, Filial 1 (F1), Filial 2 (F2)
F1 is the hybrid of parents, and F2 is the offspring of self-fertilized hybrids.
What is an allele?
A different version of a gene. Codes for specific traits, ie brown eyes.
What does the Law of Independent Assortment state?
The alleles of different genes are sorted independently of each other. Different traits do not affect each other.
What does the Law of Segregation state?
Each individual has two alleles for a gene which they inherited one from each parent.
What is the difference between homozygous and heterozygous?
Homozygous = two of the same alleles at one gene (AA or aa)
Heterozygous = two different alleles at one gene (Aa)
What structure of DNA was discovered in 1953? Who discovered it?
Double helix DNA structure. Discovered by Crick and Watson, Wilkins.
What are the four nitrogen bases in DNA?
- Adenine
- Thymine
- Guanine
- Cytosine
Describe characteristics of DNA.
- double helix structure
- nucleotides (phosphate, deoxyribose sugar, nitrogen bases)
Describe characteristics of RNA.
- single helix structure
- nucleotides (phosphate, ribose sugars, and nitrogen bases)
What replaces Thymine in RNA.
Uracil.
How many chromosomes do humans have?
46 chromosomes total
Ie 23 pairs. This includes 22 autosomal pairs and 1 sex pair.
What is a chromatid?
A single chromosome fiber.
Explain the process of genetic duplication.
DNA is unzipped by helicase enzyme. Then complementary pairing ad duplication occurs.
Explain mitosis versus meiosis.
Mitosis = cell division to produce daughter cells
Meiosis = division of cells to produce four unique gametes
What is genetic recombination?
Formation of unique daughter cells from parent cells. Important for evolution, creates genetic diversity.
List the 4 forces of evolution.
- Natural selection
- Mutation
- Genetic Drift
- Gene flow
What is genetic drift?
Change in gene frequencies in a population due to random chance.
What is gene flow?
Movement of genes into or out of a population. Ie a group of white bunnies can mate with a group of black bunnies and change each others population genes.
What are mutations?
Change in genetic makeup that creates new genetic material. Can be harmful, beneficial, or neutral.
What are the 2 types of mutations?
Point mutation = change in only one gene
Frame shift mutation = insertion or deletion of DNA section.
