Honors Intro to Biology - Dynamic Study Module Review

Polytomy

A polytomy is a branching point in a phylogenetic tree where more than two descendant groups arise from a single ancestral lineage. It indicates uncertainty in the evolutionary relationships among those groups.

Maximum parsimony

A method used in phylogenetics that seeks to minimize the total number of evolutionary changes when constructing a tree. It helps to create the simplest tree possible based on given data.

Cladistic analysis

A method of classifying organisms based on the branching patterns of evolution and shared characteristics, used to reconstruct evolutionary relationships.

Taxon

A taxon is a group of one or more populations of organisms which forms a unit of classification within a phylogenetic hierarchy. This can include species, genera, families, and other ranks.

Horizontal gene transfer

A process in which an organism transfers genetic material to another organism that is not its offspring. Mechanisms of bacterial horizontal gene transfer include transformation, transduction, and conjugation. Occurs in both prokaryotes and eukaryotes.

Orthologous

genes that diverged after a speciation event, retaining the same function in different species. (homologous genes but different species)

Analogous

genes that have similar functions but evolved independently in different species.

Homologous

genes that share a common ancestor and may have similar functions or structures.

3 domain vs. 5 kingdom

Phylogenies based on genetic data revealed that some prokaryotes (kingdom Monera) differ as much from each other as they differ from eukaryotes.

Phyletic

Relating to or denoting the evolutionary development of a species or other group.

Natural theory

Darwinian selection does not influence a lot of evolutionary change in genes and proteins because many of these changes do not affect fitness.

Allopatric speciation

A mode of speciation where geographic barriers isolate populations, leading to genetic divergence and the formation of new species.

Biological species concept

The definition that defines a species as a group of organisms capable of interbreeding and producing fertile offspring, emphasizing reproductive isolation.

Autopolyploid

Where an error in cell division during meiosis resulted in a tetraploid individual with double the number of chromosomes as the diploid parent species, which then became reproductively isolated from the original diploid population, leading to the formation of a new species. 

Speciation

The evolutionary process where a single lineage splits into two or more distinct species that are reproductively isolated from each other. This process can be driven by geographic isolation (allopatric speciation), which prevents gene flow, or by other factors like behavioral changes or ecological shifts (sympatric speciation)

Punctuated equilibrium model of evolution

The hypothesis that evolutionary development is marked by isolated episodes of rapid speciation between long periods of little or no change.

Macroevolution

evolutionary changes above the level of a species

Microevolution

a change in allele frequencies within a population over time

Why is RNA, rather than DNA, thought to have been the first genetic material?

Because RNA can act as a catalyst

Which of the following is an internal structure that appears in eukaryotic cells and is also present in more ancient prokaryotic cells?

Vesicles

What is the 4 stage hypothesis for a biotic life?

suggests a gradual increase in complexity from non-living matter to early life forms

The original atmosphere of Earth had little oxygen. What was the likely first source of oxygen that led to an oxygen atmosphere?

Cyanobacteria

Hox gene

"master regulator" genes essential for the proper embryonic development of all animals, determining the placement of body parts and influencing the evolution of body plans

The correct ordering of geologic time divisions from largest to smallest is:

Eon, Era, Period, Epoch, Age

Hardy-Weinberg equilibrium

a population genetics principle stating that allele and genotype frequencies in a population remain constant from generation to generation if no other evolutionary influences are present

Genetic drift

a random change in allele frequencies in a population

A(n) __________ is the smallest unit that can evolve.

population

Organisms found only in specific places in the world are referred to as _________

endemic species

How are retroviruses different from other types of viruses?

They are different from other types of viruses because they use the enzyme reverse transcriptase to transcribe a copy of DNA from their own RNA.

Bacteriophage

Viruses that infect bacteria