DNA replication is initiated when helicase enzyme breaks the hydrogen bonds holding the base pairs together and the DNA uncoils.
Transfer RNA; the type of RNA that carries an amino acid from the cytoplasm to the ribosome for incorporation into a growing protein.
Ribosomal RNA; the type of RNA that associates with ribosomal proteins to make a functional ribosome.
The assembly of a protein on a ribosome, using mRNA to direct the order in wich amino acids are added to the protein being made.
A cell organelle which functions as the site of protein synthesis in the cytoplasm; consists of rRNA and protein molecules, which make up two subunits.
a regulatory protein that binds to an operator and blocks transcription of the genes of an operon
controls the activity of the structured genes (switches on/off to control transcription)
a type of point mutation that results in an alternate incorrect amino acid to be coded; produces a disfunctional protein
a mutation that changes an amino acid codon to one of the 3 stop codons, resulting in a shorter and usually nonfunctional protein
The branch of biology that studies the ways in which heredity information is passed on from parents to offspring.
____ is considered the "father of genetics"....was the first to use the experimental method to study inheritance.
the crossing of an individual of unknown genotype with a homozygous recessive individual to determine the genotype of the unknown individual
law of segregation
Mendel's law that states that the pairs of homologous chromosomes separate in meiosis so that only one chromosome from each pair is present in each gamete
principle of dominance
states that if a dominant allele is present, it will be expressed in an organism
describes a trait or an allele that is expressed only when two recessive alleles for the same characteristic are inherited
law of independent assortment
states that allele pairs separate independently during the formation of gametes
a sex-linked recessive disorder defined by the absence of one or more of the proteins required for blood clotting
chorionic villus sampling
removal of a small piece of the chorion for genetic analysis; may be done at an earlier stage of pregnancy that amniocentesis
autosomal-dominant genetic disorder which affects cognitive and mental abilities
a medical procedure in which a sample of cells from the amniotic fluid is tested for abnormalities in a fetus
Chorionic Villi Sampling
sampling of cells from the chorion to test for genetic conditions in a fetus. The cells are grown in a special medium after which a karyotype can be used to make a diagnosis.
enables direct observation of the fetus through an endoscope to allow medical professionals to safely perform various procedures directly inside the womb
_______________ is being tested as one way to reverse some of the effects of genetic disorders
Chorionic Villi Sampling
Used to test for genetic defects and can be done as early as the ninth week of pregnancy
enzymes which recognize a specific short sequence of nucleotides (the target sequence) on a strand of DNA and cut the strand at a particular point within that sequence
segments of DNA from two different species that are joined in a laboratory to form a single molecule of DNA
Polymerase Chain Reaction
almost entirely automated method of replicating DNA that allows researchers to target and amplify a very specific sequence within a DNA sample
a process in which an identical copy of an organism or part of an organism that has the same genetic make-up, such as the offspring of asexual reproduction, a general term for the research activity that creates a copy of some biological entity (a gene or organism or cell)
Human Genome Project
Determined the sequence of three billion base pairs that make up the human genome
process by which individuals that are better adapted to the environment are more likely to survive and reproduce than others
Hutton and Lyell
scientists who proposed the Earth was millions of years old due to their geological findings.
scientist who proposed natural events caused previous animal species to become extinct.
predicted the population would outgrow the food source if restrictions were not put in place
French naturalist who proposed that evolution resulted from the inheritance of acquired characteristics
body structure that has no function in a present day organism but was useful to an ancestor
a model of evolution in which gradual change over a long period of time leads to biological diversity
is the idea that the geologic processes that operate today also operated in the past
theory stating that in the absence of forces that change the proportions of alleles at a give locus, the original genotype proportions will remain constant from one generation to the next, in a large population with random mating
the change in frequencies of particular alleles in a small population, caused by chance alone
movement of new genes into a gene pool. This movement can reduce difference between populations that were caused by isolation and genetic drift.
any situation in which individuals do not choose mates on a random basis, such as mating in base don proximity, relatedness, or similarity of phenotype
cause of genetic drift due to a small group of individuals colonizing a new area; the small group probably will not contain all the genes represented in the parent population
occurs when a population is greatly reduced by events such as natural disaster or over hunting, resulting in certain alleles being overrepresented and other alleles being underrepresented or absent in the population due to chance
type of non-random mating in which individuals choose partners that have similar phenotype such as size
selection for mating based in general on competition between males and choices made by females (ie. humans)
theory that life on Earth occurred began as the natural result of the evolution of inorganic matter
suggest that life originated elsewhere in the universe and then migrated to our planet
view that earth is a living super organism which is maintained and regulated by life on its surface
intelligent design theory
suggests that life mechanisms are too complex to have evolved by chance, must have been directed by an unidentified supernatural intelligence
the merging of organisms into new collectives; development of a new species through close association of organisms of different species that is of mutual benefit