Biology Final Exam Review

translation

(genetics) the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm; involves tRNA

inherited trait

A characteristic that is passed from parent to offspring.

karyotype

A display of the chromosome pairs of a cell arranged by size and shape.

sex linked trait

Characteristic such as red-green color blindness, controlled by genes on the X chromosome also called an X linked trait.

biosphere

Consists of all life on Earth and all parts of the Earth in which life exists, including land, water, and the atmosphere.

carbon cycle

Cyclic movement of carbon in different chemical forms from the environment to organisms and then back to the environment.

variation

Difference among members of a species

cell differentation

Process by which cells become different types of cells

complementary sequence

For a given sequence of nucleic acids, the nucleic acids that are related to them by the rules of base pairing (A goes w/ T & C goes with G)

homeostasis

Process by which organisms maintain a relatively stable internal environment.

messenger RNA

Type of RNA that carries genetic information from DNA in the nucleus to direct protein synthesis in the cytoplasm; process of making it is called transcription

haploid

a cell with only one complete set of chromosomes

genetic mutation

a change of the sequence of a DNA molecule

Punnett Square

a chart that shows all the possible combinations of alleles that can result from a genetic cross

reactant

a chemical substance that is present at the start of a chemical reaction

food web

a community of organisms where there are several interrelated food chains

population

a group of organisms of the same species populating a given area

organic matter

any substance that is made of living things or the remains of living things

amino acid

building blocks of proteins (combo of 20 different ones)

interphase

cell grows, performs its normal functions, and prepares for division; consists of G1, S, and G2 phases

biological molecule

chemical compounds that provide physical structure and bring about movement, energy use, and other cellular functions in a living organism

phenotype

physical characteristics of an organism

independent assortment

principle that genes do not influence each other's inheritance because they are separated independently during meiosis

gene expression

process by which a gene produces its product and the product carries out its function

sexual reproduction

process by which cells from two different parents unite to produce the first cell of a new organism

photosynthesis

process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars (glucose)

DNA replication

process of copying DNA molecules

cellular respiration

process that releases energy by breaking down glucose and other food molecules in the presence of oxygen

genetic diversity

the amount of variation in the genetic material within all members of a popualtion

chemical bond

the attractive force that holds atoms or ions together where the energy in a compound is stored

allele

the different forms of a gene; Example: A or a

deletion

the loss of a part of DNA from a chromosome

cell differentiation

the process by which a cell becomes specialized for a specific structure or function

cell specialization

Cells throughout an organism can develop in different ways to perform different tasks.

transcription

(genetics) the organic process whereby the DNA sequence in a gene is copied into mRNA

inversion

(genetics) a kind of mutation in which the order of the genes in a section of a chromosome is reversed

diploid

(genetics) an organism or cell having two sets of chromosomes or twice the haploid number (2N)

eukaryote

A more complex cell that contains a nucleus and membrane bound organelles

insertion

A mutation involving the addition of one or more nucleotide pairs to a gene.

endangered species

A species whose numbers are so small that the species is at risk of extinction

sex cell

An egg or sperm cell (gamete); a sex cell carries half the number of chromosomes found in other body cells.

ribosome

An organelle that functions in the synthesis of proteins

detritivore

An organism (like the earthworm) that feeds on decaying matter after it has been broken down by decomposers.

heterotroph

An organism that cannot make its own food and thus eats other organisms

autotroph

An organism that makes its own food.

somatic cells

Any cells in the body other than reproductive cells

mendelian genetics

The branch of genetics concerned with patterns and process of inheritance. Dominant and recessive genes in one generation determine their proportions in the next generation

cytokinesis

The final stage of the cell cycle, in which the cell's cytoplasm divides, distributing the organelles into each of the two new cells.

genetic recombination

The general term for the production of offspring with new combinations of traits inherited from the two parents.

ecological succession

The gradual and orderly process of change in an ecosystem brought about by the progressive replacement of one community by another until a stable climax is established

energy flow

The passage of energy through the components of an ecosystem

DNA sequence

The sequence, or order, in which the nitrogenous bases adenine (A), cytosine (C), guanine (G), and thymine (T) are arranged in a gene or a DNA fragment, or in an organism's genome.

human genetics

The study of how some traits appear and others disappear in the process of heredity

genetic variation

The variety of different types of genes in a species or population.

protein

a molecule that is made up of amino acids and that is needed to build and repair body structures and to regulate processes in the body, ie does everything

frame shift mutation

a mutation involving the addition or loss of nucleotides; every codon beyond the gene is effected

DNA subunit

a nucleotide; It consists of a sugar (deoxyribose), a phosphate group, and a nitrogenous base (adenine, thymine, guanine or cytosine)

meiosis

a process in cell division during which the number of chromosomes decreases to half the original number by two divisions of the nucleus, which results in the production of sex cells

asexual reproduction

a reproductive process that involves only one parent and produces offspring that are identical to the parent

recessive trait

a trait that is apparent only when two recessive alleles for the same characteristic are inherited

global warming

an increase in the average temperature of the earth's atmosphere (especially a sustained increase that causes climatic changes); some believe its caused by humans whereas others say its a natural occurence

producer

an organism that makes its own food

consumer

an organism that obtains energy by feeding on other organisms

genotype

an organism's genetic makeup, or allele combinations

DNA

deoxyribonucleic acid; the genetic material that carries information about an organism that is passed from parent to offspring AND is used by an individual as the recipe for making proteins

cancer

disorder in which some of the body's own cells lose the ability to control growth

gamete

egg or sperm (haploid)

product

element or compound produced by a chemical reaction

crossing over

exchange of genetic material between homologous chromosomes during prophase I of meiosis

trophic level

feeding level in an ecosystem; each step in the food chain or web

protein synthesis

forming proteins based on information in DNA and carried out by RNA; two parts - transcription & translation

carbon dioxide

gas that is a byproduct of respiration. Plants need it to perform photosynthesis. Involved in carbon cycle & burning of fossil fuels

logistic growth

growth pattern in which a population's growth rate slows or stops following a period of exponential growth

exponential growth

growth pattern in which the individuals in a population reproduce at a constant rate

heterozygous

having two different alleles for a trait

chromosome pair

identical copies of a single chromosome copy of mom chromosome 1 next to mom chromosome 1

chromosome

in a eukaryotic cell, one of the structures in the nucleus that are made up of DNA and protein; in a prokaryotic cell, the main ring of DNA

carrying capacity

largest number of individuals of a population that a environment can support

biotic

living

greenhouse effect

natural situation in which heat is retained in Earth's atmosphere by carbon dioxide, methane, water vapor, and other gases

abiotic

non-living

progeny

offspring

sex chromosome

one of two chromosomes of the 23rd pair of human chromosomes, which determine an individual's gender (X or Y)

homologous chromosome

one of two paired chromosomes, one from each parent, that carries genes for a specific trait at the same location

ecology

scientific study of interactions among organisms and between organisms and their environment

gene

sequence of DNA that codes for a protein and thus determines a trait

invasive species

species that enter new ecosystems and multiply, harming native species and their habitats

mitosis

the stage of the cell cycle during which the cell's nucleus divides into two new identical nuclei and one copy of the dna is distributed into each daughter cell; asexual reproduction

biomass

the total mass of living matter in a given unit area

ecosystem stability

the total number of species is fairly consistant from year to year---the same species were present each year--- the population size of each species was approximately the same from year to year

dominant trait

the trait observed when at least one dominant allele for a characteristic is inherited

nitrogen cycle

the transfer of nitrogen from the atmosphere to the soil, to living organisms, and back to the atmosphere

polygenic trait

trait that is controlled by two or more gene combinations

codominant trait

two alleles are dominant at the same time (blood type is an example ---AB are codominant)

double helix

two strands of nucleotides wound about each other; structure of DNA

transfer RNA

type of RNA molecule that transfers amino acids to ribosomes during protein synthesis

stem cell

unspecialized cell that can develop into a specialized cell under the right conditions

point substitution

when one nucleotide is substituted for another