Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
103 Cards in this Set
- Front
- Back
|
Genetics
|
study of how traits are inherited from one generation to the next
|
|
|
Gene
|
basic unit of heredity
|
|
|
Allele
|
alternative form of gene when genes exist in more than one form
|
|
|
Genotype
|
genetic makeup of an individual
|
|
|
Phenotype
|
physical manifestation of the genetic makeup
|
|
|
Gregor Mendel's experiment
|
-garden pea experiment
-studied inheritance of individual pea traits by performing genetic crosses |
|
|
True breeding individual
|
individual that if self-crossed produce progeny only with the parental phenotype
|
|
|
Mendel's Law of Segregation
|
-genes exist in alterative forms(alleles)
-there are 2 alleles for each inherited trait, one from each parent -2 alleles segregate during meiosis, resulting in gamete carrying one allele for a trait -if 2 alleles are different, one will be fully expressed and other silent |
|
|
Expressed Allele
|
Dominant allele
|
|
|
Silent Allele
|
Recessive allele
|
|
|
Monohybrid cross
|
cross performed when one trait is being studied
|
|
|
Parental generation
|
individuals that are being crossed
|
|
|
Filial generation
|
progeny generation (f generation)
|
|
|
Dominant Homozygous gene
|
Capital letters
|
|
|
Recessive Homozygous gene
|
Lower case letters
|
|
|
Test cross
|
-used to determine unknown genotype
-can be best predicted using recessive phenotype |
|
|
Mendel's Law of Independent Assortment
|
-genes of unlinked chromosomes assort independently during meiosis while doing a dihybrid cross
-genes of same chromosome stay together unless crossing over occurs |
|
|
Incomplete Dominance
|
-progeny phenotype are blends of parental phenotypes
-phenotype of heterozygote is an intermediate of phenotype of homozygotes |
|
|
Codominance
|
-multiple alleles exist for a gene with more than one being dominant
-ex. ABO blood groups |
|
|
Autosomes
|
pairs of homologous chromosomes in sexually differentiated species
-humans have 22 pairs |
|
|
Sex chromosomes
|
-sex is determined by them
-females: homozygous X -males: heterozygous XY |
|
|
Sex linked gene
|
genes that are located on the X or Y chromosome
|
|
|
Sex linked recessive gene
|
-ex: hemophilia & color blindness
-affected males can't pass the trait to male offspring but will pass to all daughters |
|
|
Advantages of studying Drosophila Melanogaster
|
-short life cycle
-reproduction in large # -chromosomes are large(size & shape) -has 4 pairs of chromosomes -mutations occur frequently |
|
|
nondisjunction
|
-failure of homologous chromosomes to separate during meiosis I or failure of sister chromatids to separate during meiosis II
|
|
|
trisomy
|
-zygote that has three copies of chromosomes
-result from nondisjunction -ex. down syndrome(trisomy of chromosome 21) |
|
|
monosomy
|
-zygote that has one copy of chromosome
-result from nondisjunction |
|
|
Chromosomal breakage
|
-can occur spontaneously or through environment
-chromosome loses fragment |
|
|
mutation
|
-change in genetic information of cell, coded in regions of DNA mostly not coded for proteins & silent
-in somatic cell: lead to tumor -in gametes: transmitted to offspring |
|
|
mutagenic agent
|
-induce mutations
-like cosmic rays, x-rays, uv rays, radioactivity -are carcinogenic |
|
|
colchicine
|
chemical that inhibits spindle formation causing polyploidy or mustard gas
|
|
|
mutation types
|
-gene mutation: nitrogen bases are added, deleted, substituted
-mutated protein: inappropriate amino acids inserted into polypeptide chain |
|
|
Phenylketonuria(PKU)
|
molecular disease caused by inability to produce enzyme for metabolism of phenyalanine
-phenylpyruvic acid accumulates as a degraded product |
|
|
Sickle-cell anemia
|
-deficiency in hemoglobin in RBC
-carries less oxygen -caused by substitution of valine(GUA or GUG) for glutamic acid (GAA or GAG) |
|
|
DNA
|
-deoxyribonucleic acid
-contains information coded on base pairs which provide for protein synthesis -has ability to self-replicate -mutable -sugar-phosphate chain on outside of double helix, while base on inside |
|
|
Nucleotide
|
-basic unit of DNA
-contains deoxyribose(sugar), phosphate group, and nitrogenous base -contains two types of bases: purines and pyrimidines |
|
|
Purines
|
-adenine(A)
-guanine(G) |
|
|
Pyrimidine
|
-cytosine(C)
-thymine(T) (CUT the PY) |
|
|
hydrogen bonds of T & A
|
2
|
|
|
hydrogen bonds of G & C
|
3
|
|
|
Genetic code of DNA
|
-write 20 amino acid to form 64 codons by amino acid degeneracy/redundancy
-1 amino acid=more than one codon -1 codon=1 amino acid |
|
|
RNA
|
-ribonucleic acid
-sugar is ribose -contains uracil(U) instead of thymine -single stranded -can be found in nucleus or cytoplasm -types of RNA: mRNA, tRNA, rRNA |
|
|
mRNA
|
-messenger RNA
-carries complement DNA sequence and transports it from nucleus to ribosomes for protein synthesis -monocistronic-one mRNA strand codes for one polypeptide |
|
|
tRNA
|
-transfer RNA
-small RNA found in cytoplasm that aids in translation of mRNA's nucleotide -bring amino acid to ribosome for protein synthesis -at least 1 type of tRNA for 1 amino acid |
|
|
rRNA
|
-ribosomal RNA
-structure component of ribosome -most abundant of all RNAs -synthesized in nucleolus |
|
|
Transcription
|
process by which information in DNA is transcribed to strand of mRNA, to cytoplasm through nuclear pores
|
|
|
Translation
|
mRNA codons translated to amino acids
-occurs in cytoplasm 1. tRNA brings amino acid to cytoplasm (one side to mRNA & other to amino acid+tRNA) 2. ribosomes have one binding site for mRNA and two for tRNA(P site and A site) |
|
|
Polypeptide synthesis
|
-initiation
-elongation -termination |
|
|
Initiation
|
1. Ribosome binds to mRNA near it's 5' end
2. scan mRNA till start codon(AUG) 3. bring aminoacyl-tRNA complex base pair with start codon |
|
|
Elongation
|
1. Hydrogen bonds form between mRNA codon in A site with complementary anticodon of aminoacyl-tRNA complex
2. Peptide bond formed between amino acid in A site and P site |
|
|
Translocation
|
1. ribosome advances 3 nucleotides at a time from 5'->3' end
2. uncharged tRNA is expelled through E site and chain moves from A to P site |
|
|
Termination
|
1.occurs when one of the mRNA termination codons(UAA, UAG, or UGA) arrives at A site
|
|
|
Bacterial Genome
|
-consists of single circular chromosome located in nucleoid region
-also contains plasmid -replication occurs in both directions -DNA synthesis from 5'->3' |
|
|
Binary fission
|
-asexual reproduction of bacterial cell
|
|
|
Mechanisms for increasing genetic variance of bacteria
|
-transformation
-conjugation -transduction |
|
|
Transformation
|
foreign plasmid incorporated into bacterial chromosome via recombination
|
|
|
Conjugation
|
-sexual mating in bacteria by transfer of genetic material with bacteria temporarily joined
-cytoplasmic conjugation bridge formed from donor male(+) to recepient female(-) -only bacteria with plasmid called sex factors can conjugate -best sex factor is F factor in E. coli -Hfr cells, high frequency recombination of genes before conjugation bridge breaks |
|
|
Transduction
|
occurs when fragments of bacterial chromosome accidently package to viral progeny produced during viral infection. This infects other bacteria in return
|
|
|
Recombination
|
-linked genes are separated
-occurs when different genes of same traits are crossed |
|
|
Transcription
|
-depends on accessibility of RNA polymerase to genes
-directed by operon |
|
|
Operon components
|
-structural gene
-operator gene -promoter gene |
|
|
Structural gene
|
sequence of DNA that codes for proteins
|
|
|
Operator gene
|
sequence of non transcribable DNA that is a repressor binding site
|
|
|
Promoter gene
|
noncoding sequence of DNA serving as initial binding site for RNA polymerase
|
|
|
Regulator gene
|
codes for synthesis of a repressor that binds to the operator & blocks RNA polymerase from transcribing structural genes
|
|
|
Inducible system
|
-repressor binds to operator, forming barrier to prevent RNA polymerase from transcribing structural gene
-then inducer bind to repressor for transcription -complex can't bind to operator so transcription occurs |
|
|
Repressible system
|
repressor is inactive until it combines with copressor
|
|
|
Bacteriophage
|
-virus that infects its host bacterium by attaching to it
-inject DNA through cell wall while protein coat staying attached to cell wall -once inside host, it goes through lytic cycle or lysogenic cycle |
|
|
Lytic Cycle
|
-phage DNA takes control & makes numerous progeny
-bacterial cell bursts releasing new virions, infecting other bacteria -bacteriophage during lytic cycle called virulent |
|
|
Lysogenic Cycle
|
if bacteriophage doesn't lyse its host cell, it becomes integrated into bacterial genome in a harmless form till a point that the prophage spontaneously goes to lytic cycle
|
|
|
Southern Blot
|
technique allowing detection of nucleotides in specific DNA sample
|
|
|
Polymerase chain reaction(PCR)
|
-technique for amplification of genes
-consists of denaturation, primer annealing, and primer extension |
|
|
Cloning DNA in bacteria
|
-technique for amplification of genes by ligation of DNA sequence with vector DNA fragment
|
|
|
Promoter gene
|
noncoding sequence of DNA serving as initial binding site for RNA polymerase
|
|
|
Regulator gene
|
codes for synthesis of a repressor that binds to the operator & blocks RNA polymerase from transcribing structural genes
|
|
|
Inducible system
|
-repressor binds to operator, forming barrier to prevent RNA polymerase from transcribing structural gene
-then inducer bind to repressor for transcription -complex can't bind to operator so transcription occurs |
|
|
Repressible system
|
repressor is inactive until it combines with copressor
|
|
|
Bacteriophage
|
-virus that infects its host bacterium by attaching to it
-inject DNA through cell wall while protein coat staying attached to cell wall -once inside host, it goes through lytic cycle or lysogenic cycle |
|
|
Lytic Cycle
|
-phage DNA takes control & makes numerous progeny
-bacterial cell bursts releasing new virions, infecting other bacteria -bacteriophage during lytic cycle called virulent |
|
|
Lysogenic Cycle
|
if bacteriophage doesn't lyse its host cell, it becomes integrated into bacterial genome in a harmless form till a point that the prophage spontaneously goes to lytic cycle
|
|
|
Southern Blot
|
technique allowing detection of nucleotides in specific DNA sample
|
|
|
Polymerase chain reaction(PCR)
|
-technique for amplification of genes
-consists of denaturation, primer annealing, and primer extension |
|
|
Cloning DNA in bacteria
|
-technique for amplification of genes by ligation of DNA sequence with vector DNA fragment
|
|
|
Promoter gene
|
noncoding sequence of DNA serving as initial binding site for RNA polymerase
|
|
|
Regulator gene
|
codes for synthesis of a repressor that binds to the operator & blocks RNA polymerase from transcribing structural genes
|
|
|
Inducible system
|
-repressor binds to operator, forming barrier to prevent RNA polymerase from transcribing structural gene
-then inducer bind to repressor for transcription -complex can't bind to operator so transcription occurs |
|
|
Repressible system
|
repressor is inactive until it combines with copressor
|
|
|
Bacteriophage
|
-virus that infects its host bacterium by attaching to it
-inject DNA through cell wall while protein coat staying attached to cell wall -once inside host, it goes through lytic cycle or lysogenic cycle |
|
|
Lytic Cycle
|
-phage DNA takes control & makes numerous progeny
-bacterial cell bursts releasing new virions, infecting other bacteria -bacteriophage during lytic cycle called virulent |
|
|
Lysogenic Cycle
|
if bacteriophage doesn't lyse its host cell, it becomes integrated into bacterial genome in a harmless form till a point that the prophage spontaneously goes to lytic cycle
|
|
|
Southern Blot
|
technique allowing detection of nucleotides in specific DNA sample
|
|
|
Polymerase chain reaction(PCR)
|
-technique for amplification of genes
-consists of denaturation, primer annealing, and primer extension |
|
|
Cloning DNA in bacteria
|
-technique for amplification of genes by ligation of DNA sequence with vector DNA fragment
|
|
|
Promoter gene
|
noncoding sequence of DNA serving as initial binding site for RNA polymerase
|
|
|
Regulator gene
|
codes for synthesis of a repressor that binds to the operator & blocks RNA polymerase from transcribing structural genes
|
|
|
Inducible system
|
-repressor binds to operator, forming barrier to prevent RNA polymerase from transcribing structural gene
-then inducer bind to repressor for transcription -complex can't bind to operator so transcription occurs |
|
|
Repressible system
|
repressor is inactive until it combines with copressor
|
|
|
Bacteriophage
|
-virus that infects its host bacterium by attaching to it
-inject DNA through cell wall while protein coat staying attached to cell wall -once inside host, it goes through lytic cycle or lysogenic cycle |
|
|
Lytic Cycle
|
-phage DNA takes control & makes numerous progeny
-bacterial cell bursts releasing new virions, infecting other bacteria -bacteriophage during lytic cycle called virulent |
|
|
Lysogenic Cycle
|
if bacteriophage doesn't lyse its host cell, it becomes integrated into bacterial genome in a harmless form till a point that the prophage spontaneously goes to lytic cycle
|
|
|
Southern Blot
|
technique allowing detection of nucleotides in specific DNA sample
|
|
|
Polymerase chain reaction(PCR)
|
-technique for amplification of genes
-consists of denaturation, primer annealing, and primer extension |
|
|
Cloning DNA in bacteria
|
-technique for amplification of genes by ligation of DNA sequence with vector DNA fragment
|
