BIO 3060 - Exam 1 - Definitions

Terms and Definitions from slides in class

Evolution

Change in gene frequencies in a population of organism over time.

Hardy-Weinberg Principle

A tool to determine if a population is evolving.

Selective Mating

Mating may be non-random

Genetic Drift

Changes in gene frequencies due to random chance events

Natural selection

Can result in changes in allele freqencies that produce populations that are adapted to the environment.

Adaptation

genetically determined characteristics that enhances the ability of organism to cope with their environment.

Fitness

Contribution to future generationsthrough reproduction and survival. B

Biomes

Large complexes of communities characterized by a distinctive vegetation type and climate.

Salinity

amount of salt dissolved in water

Intertidal Zones

margins between ocean and land.

Population

Group of individuals of the same species occurring in the same area; Can interbreed successfully.

Abundance

Number of individuals in a population.

Demography

Study of processes that affect abundances.

• Birth

• Death

• Emigration

• Immigration

Population Density

Number of organisms per area volume.

Distribution

where the population occurs

Dispersion

Distribution or spacing of individuals within the population

Population range

all the areas in which individuals of a species occur

Cohesion

hydrogen bonds hold the substance together

Adhesion

clinging of one substance to another

Surface tension

a measure of the force neccesary to stretch or break the surface of a liquid

Heat

a measure of the total quantity of kinetic energy due to molecular motion in a body of matter

Temperature

Measures the intensity of head due to the average kinetic energy of molecules

Heat of vaporization

is the quantity of heat that a liquid must absorb for 1g of it to be converted from the liquid to a gaseous state.

solution

liquid that is completely homogeneous mixture of two or more substances

solvent

Dissolving agent

solute

substance that is dissolved

hydrophilic

any substance that has an afinity for water

hydrophobic

substances that have no affinity for water

Acid

a substance that increases the hydrogen ion concentration in a solution

Base

Any substance that reduces the hydrogen ion concentration in a solution

Buffers

resist changes to the pH of a solution by neutralizing added acids or bases

Acid Precipitation

occurs when rain, snow, or fog has a pH that is more acidic than 5.6