Quiz set Flashcards
What are the three parts of a nucleotide?
Nitrogen base, Phosphate, Deoxyribose
What are the four nitrogen bases?
Thymine, Adenine, Guanine, Cytosine
How do the bases pair up?
A-T, C-G
Why are the bases and their order important?
Because every base needs to match up correctly to work.
What is the shape of DNA called?
Double Helix
Define dominant and recessive.
Dominant-The trait that will appear
Recessive-The trait that will only appear with the absence of a recessive allele
What is the difference between a genotype and phenotype?
Genotype-Genetic code
Phenotype-The physical appearance of that code
Define Homozygous and Heterozygous
Homozygous-Same alleles
Heterozygous-Different alleles.
What is an allele?
One member of a pair of genes
How is sickle cell anemia an example of natural selection in humans?
Because sickle cell anemia was when red blood cells looked like a crissoint but helped the person become more resistant to malaria.
In an area with Malaria, why is heterozygous the best option for a carrier of the sickle cell allele?
Because one normal gene and one sickle cell gene was the best at stopping malaria.
Define each step to a NEW SPECIES
Separation: Part of a population becomes isolated from the rest.
Define each step to a NEW SPECIES
Adaptation: Natural Selection constantly improves fit between species & environment.
Define each step to a NEW SPECIES
Divergence: Differences start to build genetically and behaviorally
What is gene frequency?
a measurement of how frequent an allele is in a population.
How is genetic drift different from natural selection?
Genetic drift is random and natural selection is not.
What is the Hardy-Weinberg Equilibrium?
States that allele frequencies in a population will remain constant unless one or more factors cause those frequencies to change.
Explain the equation p + q = 1
describes the frequency in alleles in a population.
What are the 5 conditions to maintain Hardy-Weinberg equilibrium?
- THERE MUST BE RANDOM MATING
- THE POPULATION MUST BE VERY LARGE
- THERE CAN BE NO MOVEMENT INTO OR OUT OF THE POPULATION
- NO MUTATIONS
NO NATURAL SELECTION
