Review of Rocks, Fossils, and Evolution

Vocabulary flashcards based on the provided lecture notes about rocks, fossils, and evolution.

Faunal Layers

Specific layers of rock containing fossils or animal remains that help scientists understand the past.

Index Fossils

Fossils used to represent a particular geologic age and identify/date the rock in which they are found.

Body Fossils

Body remains of an ancient organism that stay relatively unaltered, often the harder parts like shells or bones.

Trace Fossils

Preserved signs of the activity or behavior of an organism, such as tracks, footprints, or fossilized feces.

Mold (Fossil)

A 3-D impression of a dissolved or decayed organism left on sediment.

Cast (Fossil)

A new rock formed when liquids and minerals fill a mold, taking the shape of the original organism.

Imprint (Fossil)

A mark left by an organism (like a bug or leaf) pressed between sediment layers before decomposition.

Geologic Timescale

Divides Earth's history into Eons, Eras, Periods, and Epochs, showing the succession of time periods.

Precambrian Time

The first three eons in Earth's history.

Paleozoic Era

An era following the Precambrian time, divided into Cambrian, Ordovician, and other periods.

Mesozoic Era

An era after the Paleozoic Era, consisting of the Triassic, Jurassic, and Cretaceous periods.

Cenozoic Era

The most recent era, following the Mesozoic, divided into Paleogene, Neogene, and Quaternary periods.

Cambrian-Ordovician Extinction Event

A dramatic event marking the end of a time period, allowing for new life to evolve and diversify.

Eukaryotes

Organisms with cells containing a nucleus and other membrane-bound organelles.

Evolution

The process of biological change by which descendants come to differ from their ancestors.

Homologous Structures

Features in different organisms with similar structures but different functions, proving common ancestry.

Analogous Structures

Structures with similar functions but not similar origins, showing species are not the same.

Vestigial Structures

Once-useful structures in organisms that have lost function over time (e.g., whale's legs, human tailbones).

Cladogram

A chart showing evolutionary relationships by stacking organisms and adding traits.

Taxonomic Classification

A classification hierarchy placing organisms into groups based on similarities.

Tree of Life Model

A domain-based classification system established by Woese, currently used today.

Mitochondrial DNA

DNA passed down only from the mother, not subject to recombination.

Ribosomal RNA (rRNA)

Contained in ribosomes, it manufactures proteins.

Hox Genes

Genes that guide the development of an organism's characteristic body plan.

Genetic Variation

Varying alleles within a population.

Natural Selection

A process where alleles that harm survival are removed and beneficial traits are passed down.

Artificial Selection

Humans breeding or changing a species to bring out specific traits.

Adaptation

A feature that helps an organism survive and reproduce in its environment, a product of natural selection.

Fitness

The ability of an organism to live long enough to pass down heritable traits to offspring.

Heritable traits

Traits that are able to be passed down from generation to generation.

Systema Naturae

A new system of organization for plants, animals, and minerals based upon their similarities proposed by Carolus Linnaeus.

Darwin, Erasmus

Considered how organisms could evolve through mechanisms such as competition.

Malthus, Thomas

Argued that the increasing human population would challenge the world’s ability to supply enough food for everyone.

Uniformitarianism

The theory that both gradual and catastrophic geological changes have occurred at a constant rate on Earth and are ongoing.

Sedimentation

The buildup of rock or minerals that leads to the creation of sediment.

Faunal Succession

The layering of rock layers over time, in a specific order.

Strata

Faunal layers

Darwin, Charles

An English scientist that lead to studies on evolution after journeying to map the coast of South America and the Pacific Islands.

Wallace, Alfred Russel

A naturalist, alongside Darwin, that helped come up with principles of evolution.

Anaerobic

Don't need oxygen

Aerobic

Need oxygen

Fossil

The trace or remains of an ancient organism that is preserved in rock or sediment.

Geologic Time Scale

Divides Earth's history into intervals based on evidence found in layers of rock and the appearance and extinctions of organisms.

Tectonic plates

Large pieces of rock on Earth

Tectonic forces

Forces that make the tectonic plates move and Earth’s land shift.

Molecular Clocks

Models that use mutation rate to measure evolutionary time

Woese

Established the domain category of classification. This is the system that is currently used and is known as the tree of life model

Theory

An explanation for something based on a lot of evidence, usually from many different sources

Vertebrates

Animals that have a backbone

Invertebrates

Animals that have no backbone

Gene Pool

The collection of alleles found in all the individuals of a population

gene flow

The movement of genes into or out of a population, and can cause a population to evolve.

Genetic drift

A change in allele frequencies due to chance.

Bottleneck effects

A genetic drift that results from an event that reduces the size of a population.

Founder effects

A genetic drift that occurs when a small number of individuals become isolated from the original population and colonize a new area.

Species

A group of similar organisms that can breed and produce fertile offspring.

Speciation

The rise of two or more species from a single existing species.

Intersexual selection

A form of sexual selection in which males display certain traits that attract females

Behavioral isolation

Caused by the difference in courting or mating behaviors.

Allele frequency

The proportion of one allele, compared with all the alleles for that trait in the gene pool.

Stabilizing Selection

Intermediate phenotypes are selected over phenotypes at both extremes.

Directional Selection

Shifts the phenotypic frequencies, favoring individuals with genotypes that code for the more advantageous phenotype.

Disruptive Selection

Both extreme phenotypes are favored while the individuals with the intermediate phenotype are selected against.

Locus

A particular position, point, or place.

Homozygous

Two alleles that are the same at a specific locus

Heterozygous

Two alleles that are different at a specific locus

Gene

A piece of DNA that provides a set of instructions to a cell to make a certain protein

Allele

Any of the alternative forms or versions of a gene that may occur at a specific locus

Genotype

An organism's actual genetic makeup

Phenotype

Made up of the actual physical characteristics, or traits, of an individual

Dominant Allele

An allele that is expressed when two different alleles or two dominant alleles are present.

Recessive Allele

An allele that is only expressed when two recessive copies occur together.

Monohybrid (Cross)

A monohybrid cross is the cross of one trait

Dihybrid (Cross)

Examines the inheritance of two different traits such as Mendel’s observations of pea color and shape in his plants.

Enzyme

A protein that catalyzes chemical reactions for organisms

Polyploidy

A genetic condition where an organism has more than two complete sets of chromosomes

Mutation

Is any change in the DNA sequence

Thymine Dimer

One kind of mutation caused by a mutagen is a thymine dimer.

Point mutation

A mutation in which one nucleotide is substituted for another.

Silent mutation

Does not change the structure and function of the protein

Missense mutation

Results in a change in the codon and consequently a new amino acid.

Nonsense mutation

Results in a stop codon being formed, it will not be complete.

Frameshift mutation

Involves the insertion or deletion of one or more nucleotides in the DNA sequence.

Chromosomal Mutations

Changes in either chromosome segments or whole chromosomes

Pseudogenes

Genes that no longer function but are still carried with functional DNA

Promoter

A segment of DNA that binds to proteins that help initiate the transcription of genes.

Transcription factors

Transcribing factors are the factors that copy the genetic information of the gene

Enhancer

The enhancer makes the copying process go at normal speed rather than being super slow or super fast.

Cross

To mate as a plant.

Adaptative radiation

Speciation through the diversification of one ancestral species into many descendant species

probability

The chance that an outcome will occur

Foundation

An underlying basis or principle for something

Mendel, Gregor

An Austrian monk who laid the foundation for our current understanding of heredity

Sex Determination

The process of influencing gender

Gene linkage

The tendency that genes located close together on a chromosome get inherited together during meiosis

Punnett Square

it is a diagram used to model the cross between two parents with known genotypes

Sex-linked Traits

Are determined by genes mostly located along the X chromosome

Chromosomes

Are threadlike structures that organize and pack DNA in a cell, and contain genes

Non-disjunction

Is the failure of homologous chromosomes of sister chromatids to separate during meiosis

Karyotype

This reveals the gender of an individual, and can be used to test for chromosomal abnormalities.