Midterm Flashcards
a special sequence of nucleotides in dna that marks the ends of a gene, it signals rna polymerase to release the newley made rna molecule and then to depart from the gene
terminator
a dense body formed from a deactivated X chromosome found in the nuclei of female mammalian cells
barr body
the creation of genetically identical offspring by a single parent, without the particpation of sperm and egg
asexual reproduction
the creation of genetically unique offspring by the fusion of two haploid sex cells(gamete), forming a diploid zygote
sexual reproduction
a virus that infects bacteria
phage
phage dna that has inserted by genetic recombination into the DNA of a bacterial chromosome
prophage
the synthesis of RNA on a DNA template
transcription
the transfer of bacterial genes from one bacterial cell to another by a phage
transduction
the union of two bacterial cells or protist cells and the transfer of DNA between the two cells
conjugation
the incorporation of new genes into a cell from dna that the cell takes up from the surrounding environment
transformation
the process whereby gentic information flows from genes to proteins; the flow of genetic information from the genotype to the phenotype
gene expression
the mating between an individual of an unknown genotype for a particular character and an individual that is homozygous recessive for that same character, can be used to determine the unknown genotype
testcross
a large molecular complex that assembles DNA nucleotides using a preexisting strand of DNA as a template
DNA Polymerase
a large molecular complex that links together the growing chain of RNA nucleotides during transcription, using a DNA strand as template
RNA Polymerase
one of the two identical parts of a duplicated chromosome in a eukaryotic cells, prior to mitosis they remain attached at the centromere
Sister chromatid
the two chromosomes that make up a mached pair in a diploid cell, they are the same length, centormere position, and staining patternn and possess genesf for the same characteristics at corresponding loci
homologous chromatids
a change in the genetic information of a cell; the ultimate source of genetic diversity, occurs in DNA or RNA
mutation
the cloning of human cells by nuclear transplantation for theraputic purposes such as the generation of embryonic stem cells
therapeutic cloning
using a somatic cell from a multicellular organism to make one or more genetically identical individuals
reproductive cloning
a eukaryotic DNA sequence that helps stimulate the transcription of a gene at some distance from it, functiins by means of a transcription factor called an activator, which binds to it and then to the rest of the transcription apparatus
enhancers
a protein that switches on a gene or group of genes
activators
protein that blocks the transcription of a gene or operon
repressors
the addative effects of two or more gene loci on a signle phenotypic character
polygenic inheritance
inheritance pattern in which a heterozygote expresses the distinct trait of both alleles
codominance
a type of inhertiance in which the phenotype of a heterozygote is intermediate between the phenotypes of the two types of homozygotes
incomplete dominance
an accident of meoisis or mitosis in which a pair of homologous chromsomes or a pair of sister chromatids fail to seperate at anaphase
nondisjunction
an internal, noncoding region of gene that does not become part of the final messenger RNA molecule and is thereofore not expressed
introns
the part of a gene that becomes part of the final messenger RNA and is therefore expressed
exons
a type of regulation at the RNA processing level in which multiple mRNA molecules are produced from the same primary transcript, depending on which RNA segments are treated as exons and as intorns
alternate rna splicing
having to diffferent alleles for a given gene
heterozygous
having two identical alleles for a given gene
homozygous
allele that determines the phenotype of a gene when the individual is heterozygous for that gene
dominant
an allele that has no noticable affect on the phenotype of a gene when the individual is heterozygous for that gene
recessive
the spread of cancer cells beyong their original site
metasize
a 3 nucleotide sequence in mRNA that specifies a particular amino acid or polypeptide termination signal , the basic unit of the gentic code
codon
an RNA virus that reproduces by means of a DNA molecule , it reverse transcribes its RNA into DNA, inserts the DNA into a ciccular chromsome and then transcripbes more copies of the RNA from the viral DNA
ex: HIV
retrovirus
a display of micrographs of the metaphase chromosome of a cell, arranged by size and centromere position, used to indentify certain chromosomal abnormalities
karyotype
