Honors Bio Unit 8 Study Guide

Study Guide for Bio

What did James Hutton and Charles Lyell propose?

James Hutton and Charles Lyell proposed that the earth was very old.

What did Charles Darwin observe on his voyage?

Charles Darwin observed Natural Selection.

What was different about each island on the Galapagos Islands?

Each island had animals suited to its environment.

What is the definition of Variation?

Differences in physical traits.

What is the definition of an adaptation?

A feature that allows an organism to better survive in its environment.

What did Darwin discover about fossil and geologic evidence?

He discovered that fossil and geologic evidence changes over time.

How did Artificial Selection influence, Charles Darwin?

He compared what he learned about breeding to his idea of adaptation. He also said that in nature, environment creates selective pressure instead of humans in artificial selection.

What is Artificial Selection?

The process by which humans change species by breeding them for certain traits.

What are the four main principles of the theory of Natural Selection?

Variation, Overproduction(Lots of offsprings so few survive), Adaptation, Descent with Modificiation.

What is descent with modification?

Over time, natural selection will result in species with adaptations that are well suited for survival.

What does Natural Selection act on?

Phenotypes.

What is fitness?

The ability to survive until the age of reproduction, to find a mate, and produce offspring.

What evidence supported Darwin’s claims?

Fossils supported Darwin’s descent with modification, Geography made Darwin realize that finches found on the Galapagos islands closely resembled those found on the mainland and that over time new traits became well established in separate island populations which were caused by the different environments in each island that led to specific adaptations in diets, habits, and BEAK SHAPES, Embryology, and Anatomy where he compared body parts of different species.

What are analogous structures?

They perform a similar function but are not similar in origin(i.e. wings of bats and insects).

What are homologous structures?

Features that are similar in structure but have different functions(suggested common ancestor) (i.e. forelimbs of vertebrates).

What are vestigial structures?

Structures or organs that lack any useful function that had a function in an early ancestor(e.g. human appendix, wings of ostriches).

What is gene pool?

Genetic variation stored inside a population.

Meiosis is both…?

Recombination and Crossing over.

A bell curve is ___ distribution.

Normal.

What is directional slelection?

\

What is stabilizing selection?

What is disruptive selection?

What is gene flow?

The movement of alleles from one population to another, the receiving population has increased genetic diversity.

What is genetic drift?

changes in allele frequency due to chance.

What is the bottleneck effect?

Genetic drift that occurs after an event.

What is the founder effect?

Genetic drift that occurs after a small number of individuals colonize a new area.

What are the effects of genetic drift?

Loss of genetic variation and lethal alleles may become more common.

What is sexual selection?

When certain traits increase mating success.

The Hardy-Weinberg Equillibrium describes…

populations that are not evolving.

The Hardy-Weinberg equation is used to predict…

genotype frequencies in a population.

What is reproductive isolation?

When members of different populations can no longer mate successfully with one another.

What is behavioral isolation?

Isolation caused by differences in courtship or mating behavior,

What is Geographic Isolation?

Involves physical barriers that divide populations like mountains and rivers.

What is temporal isolation?

Timing prevents reproduction between populations.

What is convergent evolution?

Evolution towards similar characteristics in unrelated species.

What is divergent evolution?

Related species evolve in different directions and become increasingly different.

What is Coevolution?

Two or more species evolve in response to changes in each other.

What is extinction?

Elimination of a species from earth.

What is punctated equillibrium?

Bursts of evolutionary activity.

What is adaptive Radiation?

Diversification of one ancestral species into many descendant species.

What is permineralization?

Minerals carried by water are deposited around or replace the hard structure (coal).

Where do most fossils form?

In sedimentary rock.

What is relative dating?

Estimate of date by comparing the placement of fossils in rock layers.

What is radiometric dating?

Technique using natural decay rate of unstable isotopes.

What are index fossils?

Organisms that existed only during specific spans of time over a geographical area.

Eras are seperated by…

mass periods of mass destruction.

Eras last…

tens of to hundreds of millions of years.

What is the first era?

Pre-cambrian.

What is the second era?

Paleozoic.

What is the third era?

Mesozoic.

What is the fourth era(the one we are in)?

Cenozoic

How old is earth?

4\.6 billion years old.

How did the atmosphere form on earth?

When it cooled, this caused water vapor to condense and rain to fall. Organic compounds soon formed.

The Miller Urey experiment demonstrated that…

Organic compounds could be made by simulating conditions on early earth.

What is the meteorite hypothesis.

Organic molecules may have arrived on earth through meteorite or asteroid impacts.

How did single-celled organisms change Earth’s surface?

They deposited minerals.

What allowed the evolution of aerobic prokaryotes?

Higher oxygen levels in the atmosphere.

What as the first photosynthetic life to evolve?

Cyanobacteria.

What is the endosymbiotic theory?

One organism lives within the body of another, and both benefit from the relationship.

What evidence proves the endosymbiotic theory?

Mitochondria and chloroplasts have their own DNA and ribosomes, and they are similar in shape.

The is the significance of asexual reproduction in cells?

First prokaryotes and eukaryotes reproduced asexually, this increased genetic variation and was the first step in the evolution of multicellular life.

What does Homo Sapien mean?

Modern man.

How long ago did Homo Sapiens appear?

200,000 years.