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