Genetics and Evolution Review

Genetics

Gene Definition: A gene is a part of the DNA that codes for making a protein. 83% of students answered this correctly.
Phenotype vs. Genotype: Genotypes cause phenotypes. 79% of students answered this correctly. Phenotype is the observable characteristic or trait of an organism, while genotype is the genetic makeup.
Dominant Alleles: An allele that blocks the expression of another allele is considered dominant. 68% of students answered this correctly.
Homozygous vs. Heterozygous: When someone has two of the same alleles, they are homozygous, not heterozygous. 11% of students answered this incorrectly.
DNA and Protein Production: DNA has genes that code for the production of proteins in cells. 86% of students answered correctly.

Heterozygous Parents: If one parent is heterozygous for a trait and the other is homozygous dominant, 0% of the F1 generation will be homozygous recessive. 49% got this correct.
Codominance: A, B, and O blood types are not all codominant. 65% of students answered this correctly.
Polygenic Traits: A phenotype controlled by multiple genes on different chromosomes is a polygenic trait. 65% of students answered this correctly.
Incomplete Dominance: When a white chicken mates with a black chicken and has grey babies, this is an example of incomplete dominance.
Sex-linked Traits: Sex-linked genetic mutations (e.g., color blindness) most often impact males because males have only one X chromosome, so a mutation or recessive gene will be expressed. 93% of students understood this.
Recessive Inheritance: If one is homozygous recessive (blond hair) and the other is heterozygous (black hair), there is a 50% chance the children will have black hair.

Blue-eyed Children: If one parent has blue eyes (recessive) and the other has brown eyes (dominant), there is a chance to have blue-eyed children if the brown-eyed parent is heterozygous. 87% answered this correctly.

Translation: Translation is not using a DNA code to make an mRNA code. 58% answered incorrectly. Translation is the process where the genetic code in mRNA is decoded to produce a specific sequence of amino acids in a polypeptide chain.
RNA Nucleotides: Thymine is not found in RNA; Uracil is. 58% of students answered correctly.

Microevolution: Microevolution is not the evolution of a new species (speciation). 75% answered correctly.
Evolution Definition: Evolution can be used to describe a shift in allele frequency of a population because of genetic drift or natural selection. 85% of students answered that all options were correct, which included creation of new species via divergent selection, shift in allele frequency via genetic drift, or shift in allele frequency via natural selection.

Natural Selection: Natural selection is the process by which individuals with heritable traits better suited to their environment tend to survive and reproduce more successfully than individuals with out those traits.
Allele Variation: If all alleles are the same, natural selection cannot work for that trait. 54% answered correctly.
Ecological Fitness: If an organism has higher ecological fitness, it will have lots of babies. 53% got this correct, while 44% thought it meant a long life.
Mate Choice: Mate choice (sexual selection) is a type of natural selection. 84% answered correctly.

Stabilizing Selection: When the allele frequency of a population loses the extremes (white and black fur) and more individuals have the average (grey fur), this is stabilizing selection. Only 45% got this correct.

Allopatric Speciation: A new mountain range splits a population, so they evolve separately; this is allopatric speciation. 59% answered correctly.
Convergent Evolution: When species look/act the same even though they are distantly related, this is convergent evolution. 30% of students answered correctly.
Biological Species Concept: The biological species concept focuses on the ability of individuals to successfully reproduce. 86% answered correctly.

Impact of Mutations: A genetic mutation can be bad, good, or cause no change. 89% answered correctly.

Ecology Definition: Ecology is the study of interactions among species and the environment. 75% answered correctly.
Species Niche: A species niche is determined by both abiotic and biotic factors. 72% answered correctly.

Population Ecology Study: A population ecologist would study the change in abundance of lions in a national park. 58% answered correctly.
Dispersion: If individuals are randomly scattered on a landscape, you are describing the dispersion. 84% answered correctly.

Ecosystem Ecology Study: An ecosystem ecologist would NOT study how efficient lions are at catching different prey species. 61% answered correctly.

Niche Overlap: If niche overlap is too great, one species will have a competitive advantage, and the other may be excluded. 48% answered correctly.
Species Interactions: Commensalism is an interaction that has a positive impact on one species and no impact on the other. 45% answered correctly.
Gut Microbiome: Your gut microbiome is an ecological community. 72% answered correctly.
Community Succession: Community succession is the process of change in the species structure of an ecological community over time. 68% answered correctly.

Climate Change: Climate change is primarily caused by the release of carbon dioxide from burning coal, gas, and gasoline. 88% answered correctly.