Anatomy Gizmos Evolution STEM Case

A change in the traits of a population over time. Traits are characteristics like looks or behaviors. Traits come from types of genes called alleles. If the alleles change, so do the traits

Evolution happens within one species, on a small scale, over short period of tiime

Evolution happens over long period of time, on a large scale; new species can srise

If some alleles become more common over time, it's an indicator evolution has occurred

Divide number of a specific allele by the total number of alleles in a population Allele B Frequency = Number of Allele B / Total Allele Population

Cell that has two sets of DNA chromosomes. Both cats & humans are examples of diploid organisms

Both copies of genes are the same allele When individual has two of the same gene with the same allele in each gene

Two different alleles When an individual has two of the same gene with different alleles in each gene

Type of "natural selection." When humans select the traits they want in animals and plants.

Individuals with most beneficial traits will produce most offspring. Causes useful traits to become more common in a population over time. Can happen in populations with characteristics of variation & heritability

how well an organism can survive and reproduce in its environment

Allele change that increases the fitness of a population

Environmental factors that cause some individuals to have greater fitness than others. Can be either biotic or abiotic

Natural selection can change the distribution of a trait in one of three ways: directional selection, stabilizing selection, disruptive selection

Happens when one extreme trait is favored

Most common trait is favored. If it increases in fitness, it will become even more common. Less extreme traits, so less variation & population is more "stable."

When both extreme traits are more favorable. Both increase fitness & become more common in the distribution graph

Random changes (errors) in DNA that create new (also random) alleles. Their effect on fitness will also be random (can be beneficial, harmful, or have no effect at all).

Bacteria resistant to many types of antibiotics

A large group of single-celled microorganisms. Very diverse, found almost everywhere on earth

A medicine that kills or slows the growth of microorganisms

The study of heritability and variation of traits passed down as genes from parents to offspring

gene flow, genetic drift, natural selection

Changes allele frequencies when individuals move between populations. Can happen between 2 different species of bacteria

Can happen when disease or a natural disaster kills a lot of individuals. Individuals left alive reproduce & only their alleles are passed down to offspring

When a small number of individuals (the founders) leave a population & start a new one

A chemical that sticks to the DNA & looks green under a microscope. Tagging enables us to see if DNA has been transferred from one bacterium to another

A machine that creates a controlled environment that helps bacteria reproduce