Bio Semester Exam

galaxy

planets orbit a central star

Bottleneck effect

reduced genetic diversity caused by a huge decrease in population size

vestigial structures

Useless structures that are present because of a previous ancestor

monosacchride

a monomer within sugars; held together by glyosidic linkages in a polymer

cellular specialization

process in which a cell becomes tailored for a specific role in the body

bryophytes

nonvascular plants without seeds; first land plants to evolve

glucose

the monosaccharide required for cellular respiration

nebula

a cloud of dust and matter

natural selection

organisms with beneficial traits adapt to their particular environment, reproduce and pass along beneficial alleles

inflation

the rapid expansion of the universe

reduced hybrid fertility

hybrids are often sterile and cannot make more hybrids

reptiles

organisms that lay eggs, have scales and evolved stronger skeletons

Wallace

Had the same theory of natural selection as Darwin

temporal isolation

timing mechanisms prevent different species from mating

ion

an atom that has gained or lost electrons; the stable form of the atom

Homo ergaster

lived a hunter gatherer lifestyle and had smaller teeth and jaws due to a change in diet

monomer

the individual building block of a polymer

fat

a lipid with a glycerol and three fatty acids

phylogentic tree

Shows the evolutionary relationships between multiple species

r group

the only part of an amino acid that varies

niche

an organism's ecological roll in nature

glycerol

the backbone of fats and phospholipids

homologous structures

Similar structures with different functions; from divergent evolution

taxonomy

a system used to categorize organisms based on similarities with other organisms

transpiration

the evaporation of water from leaves

Australopithicus

one of the earliest hominid species identified

reproductive isolation

barriers that prevent different species from reproducing with each other

solvent

something that dissolves substances

artificial selection

occurs when humans interfere with selection pressures

amine

a functional group found within basic compounds; NH3+

photosynthesis

a process that uses solar energy to build glucose in plants

gene flow

the movement of alleles in and out of a population; increases the frequency of beneficial alleles

biosphere

all of the ecosystems on planet Earth

hybrid

the offspring of two different species who mated

convergent evolution

evolution that occurs in unrelated animals due to similar environments

evolution

when an entire species takes on a beneficial trait or characteristic; change in a species over time

punctuated equilibria

a sudden change creates a new species which then doesn't change

gene

a unit of DNA that encodes a particular RNA and protein

Malthus

Theorized that overpopulation would lead to famine

amino acid

a monomer within proteins; held together by peptide bonds in a polymer

analogous structures

Different structures with similar functions; from convergent evolution

Aristotle

Thought that living organisms were unchanging because they were made by God

chitin

the structural polysaccharide used in fungi

starch

the storage polysaccharide used in plants

quarks

the building blocks of protons and neutrons

antiparallel

the two strands of DNA run in opposite directions; one strand is right side up and the other is upside down

solution

a dissolver and something being dissolved

polysaccharide

string of monosaccharides that provide short term energy storage

molecule

two or more elements bonded together in a fixed ratio

C terminus

the end of a protein

postzygotic barrier

Something that reduces the ability of hybrids to create more hybrids

population

multiple members of the same species within a certain environment

divergent evolution

evolution of related organisms from a common ancestor

fungi

organisms that absorb their food from the soil

endemic

organisms that are specifically from a particular region

phospholipid bilayer

the cell membrane that surrounds all cells

phosphodiester bond

bond that holds nucleic acids together

mitochondria

where cellular respiration occurs in the cell

electron

subatomic particles that orbit the atomic nucleus; determine bonding

cellular respiration

a process that extracts energy from the breakdown of glucose

electronegativity

the tendency of an atom to pull electrons towards it

prokaryotes

unicellular organisms with no membrane bound organelles; some can cause disease

archae

ancient bacteria that are extremophiles; do not cause disease in humans

gymnosperms

vascular plants with seeds and no flowers

glycogen

the storage polysaccharide used in animals

cellulose

the structural polysaccharide used in plants

allopatric speciation

A geographic barrier separates a population resulting in new species

specific heat

the amount of energy required to change one gram of water by one degree Celsius

mechanical isolation

physical limitations prevent different species from mating

phloem

vasculature that carries sugar throughout a plant

sexual reproduction

an organism is created with genetic input from two sources

protein

macromolecule composed of multiple amino acids; shape is key

ester linkage

bond that holds fats and phospholipids together

gradualism

small changes over a long period of time result in a new species

base

a substance that releases hydroxide ions in solution

polar

molecules that either have a dipole or full charge

valency

the number of electrons needed to make the atom inert and stable

amphibians

organisms that live in and out of the water and reproduce in water

valence electrons

the number of electrons in the outer most electron shell

asexual reproduction

an organism creates an exact copy of itself

pterophytes

vascular plants without seeds; require water for reproduction

glycolysis

the first step of cellular respiration that starts the breakdown of glucose

mass number

the mass of the protons and neutrons in an atom

dehydration synthesis

a chemical reaction that removes water in order to join monomers together

behavioral isolation

differences in mating calls and courtship rituals prevent different species from mating

uracil

the only nitrogenous base not used in DNA

molecular dipole

partial charged caused by a polar covalent bond

aldehyde

a functional group with a carbon double bonded to an oxygen and single bonded to a hydrogen

phylogeny

the evolutionary history of an organism

prezygotic barrier

Something that prevents fertilization and formation of the zygote

element

a substance that can't be broken down by chemical means; made of atoms

biogeography

The study of how species are distributed amongst the continents

angiosperms

vascular plants with seeds and flowers

surface tension

a measure of how difficult it is to break the surface of a liquid

DNA nucleotide

phosphate group, deoxyribose and a nitrogenous base

nonpolar covalent

chemical bond which shares electrons evenly

amphipathic

molecules that contain both hydrophilic and hydrophobic regions

Pangea

a supercontinent that existed about 250 million years ago

hydrolysis

a chemical reaction that adds water in order to break down polymers

strata

layers of rock representing the geological time scale