Quarter 3 Flashcards
1
Q
Hershey + Chase
A
Used bacteriophage that infects host cans by injecting their info into the host and instructing the host to make copies of The virus
2
Q
Semi-conservative DNA replication
A
Each daughter DNA molecule is composed of one parent strand + one new strand
3
Q
helicase
A
Unwinds DNA by breaking hydrogen bonds
4
Q
Topoisomerase
A
Relieves strain of DNA strands by cutting, untwisting, + rejoining the DNA
5
Q
primase
A
Builds a short RNA primer
6
Q
DNA polymerase
A
Elongates the new strand of DNA by binding nucleotides to the 3’ end, polymerization occurs only 5’—>3’ + proofreads DNA strand during replication
7
Q
Leading strand
A
Produced continuously in the 5’—>3’ direction
8
Q
Lagging strand
A
Produced in small fragments: each fragment is produced 5’—>3’ but the fragments are added to the strand so it grows in a 3’—>5’ direction
9
Q
ligase
A
Binds DNA fragments together
10
Q
Mutagen
A
Causes a mutation
11
Q
Mismatch repair
A
Strand is proofread during replication and incorrectly paired bases are removed
12
Q
Excision repair
A
Does not occur during replication, nuclease cuts out damaged segment, nucleotides are added to fill the gap and are then bonded to existing strand
13
Q
DNA erosion
A
Each time DNA is replicated, the 5’ end of the leading strand is shortened
14
Q
Telomeres
A
Prevent DNA erosion
15
Q
When DNA has eroded too much… Is triggered
A
Apoptosis
16
Q
DNA base sequence → mRNA base sequence → amino acid sequence
A
Transcription, translation
17
Q
Where does transcription occur?
A
Nucleus in eukaryotes
18
Q
Primary transcript (mRNA)
A
Produced by reading the DNA template 3’ → 5’ and producing a complementary strand of RNA
19
Q
Promoter
A
Sequence of DNA where transcription factors and RNA polymerase bind
20
Q
Transcription: initiation
A
RNA polymerase binds to promoter region with transcription factors
21
Q
Transcription: elongation
A
New RNA nucleotides are added to 3’ end
22
Q
Transcription: termination
A
RNA polymerase reaches termination sequence in DNA and dissociates from template
23
Q
RNA splicing
A
Remove introns + connect exons
24
Q
Where does translation occur?
A
Ribosomes
25
Translation
Base sequence of mRNA read in triplets or codons to produce an amino acid sequence
26
Structure of ribosomes: A site
tRNA carrying an amino acid enters ribosome
27
28
Structure of ribosome: p site
tRNA carrying growing polypeptide
29
Structure of ribosome: E site
Exit site, innactive tRNA (nothing attached) exits the ribosome
30
Wobble
Base pairing rules for the 3rd base of codons + anticodons allowing one tRNA to bind to more than one codon
31
Where do transcription and translation occur in prokaryotes?
Cytoplasm
32
Point mutation: base pair substitution
Incorrect pase pair replaces correct base
33
Missense mutation
Mutant codon codes for different amino acid
34
Nonsense mutation
Mutant codon is now a stop codon
35
Silent mutation
Mutant codon codes for same amino acid
36
Frame shift mutation
Due to insertion or deletion
37
Double stranded DNA is wound around... Proteins to produce a...
Histone, nucleosome
38
DNA methylation
Attachment of methyl groups to DNA after synthesis
39
Histone acetylation
Attachment of acetal groups to histone proteins
40
Alternative RNA splicing
Different mRNA molecules are produced from the same primary transcript
41
Nuclease
Breaks down mRNA starting at 5' end
42
Ubiquitin
Used to mark a protein for destruction
43
siRNA
Can degrade or prevent translation of mRNA
44
Short term gene control
Cell will turn genes on/off in response to internal or external signals
45
All cells in an organism contain the same genome but cells are specialized because of...
Epic genetic mechanisms
46
Long term gene expression control
Cells become specialized through differentiation, genes that don't need to be expressed are permanently turned Off
47
3 steps of zygote → multicellular organism
Cell division → cell differentiation → morphogenesis
48
Signaling from other embryonic cells that influence the developmental path of a cell by changing gene expression
Induction
49
Events that lead to the observable differentiation of a cell
Determination
50
Specialization of cell structure
Differentiation
51
Process of an organisms body taking shape
Morphogenesis
52
Bicoid
Concentrated at anterior end of body + establishes the anterior-posterior axis
53
Master regulatory genes that control pattern formation in animals + plants
HOX genes
54
Lytic reproductive cycle
Phage directs the host cell to produce lysozyme which lyses the bacterial cell wall causing cell lysis
55
Lysogenic reproductive cycle
Viral DNA is integrated into host chromosome becoming a prophage, the viral genome is copied each line the cen divides, the cell is NOT DESTROTED
56
Plasmids
Small, circular, self replicating DNA that carry non-essential genes
57
Vertical gene transfer
Genes passed from parent to offspring
58
Horizontal gene transfer
Incorporating genetic material from another organism without being the offspring of that organism
59
Alteration of a cell's genotype + phenotype due to the uptake of foreign DNA
Bacterial transformation
60
Transduction
transfer of DNA from one cell to another through a bacteriophage
61
Direct transfer of a plasmid from one bacterium to another while temp. Joined
Conjugation
62
Section of DNA that contains several genes coding for all proteins needed for a metabolic pathway + the regulatory sequences to control expression
Open
63
Repressor protein
blocks transcription
64
Typically not expressed unless the substrate binds to the repressor, turning on gene expression
Inducible open
65
Repressible open
Typically expressed unless the product binds to the depressor
66
Expressed when the cell has taken in nutrients that need to be broken down
Lac open
67
Restriction enzymes
Used as defense to cut up viral genome + avioid infection
68
Stem cells
Relatively undifferentiated cells
69
70
Lamarck's theory of evolution: use and disuse
traits that give an organism an advantage become bigger and stronger but traits of little value diminish
71
Lamarck's theory of evolution: Inheritance of acquired traits
modifications acquired by an organism may be inherited by the next generation
72
August Weismann's experiment
tails of mice were cut off and none of the offspring inherited the tailless trait
73
How does Natural selection work?
individuals in a population with favorable phenotypes are more likely to survive and pass on the favorable traits
74
Adaptions
inherited trait that helps the organism to survive in a particular environment
75
Darwinian fitness
contributions an individual makes to the next generation
76
relative fitness
contributions of one genotype compared to alternative genotypes
77
stabilizing selection
acts against extreme phenotypes, selects intermediate phenotypes
78
directional selection
shifts overall makeup of population by favoring phenotypes of one extreme
79
diversifying selection
favors phenotypes of opposite extremes over intermediate phenotypes
80
distinction between the secondary sec characteristics of males and females
sexual dimorphism
81
gene pool
sum of all genes in a population at any one time
82
microevolution
change in the genetic structure of a population from one generation to the next
83
3 random causes of microevolution
1. genetic drift
2. gene flow
3. mutation
84
2 non-random causes of microevolution
non-random mating and natural selection
85
genetic drift
changes in a gene pool of a small population due to random chance events
86
bottleneck effect
significant reduction of the original population size due to natural disaster or overexploitation
87
founder effect
very small number of individuals from original population colonize a new habitat
88
gene flow
addition or loss of alleles from a populations gene pool due to the migration of fertile individuals or gametes
89
assortative mating
individuals select partners that are like themselves in phenotypic characters
90
polymorphism
2 or more distinct morphs/phenotypes for a particular trait in a population
91
frequency dependent selection
can maintain balanced polymorphism, the fitness of that morph may change as it becomes more or less prevalent in the population
92
diploidy
permits heterozygotes to maintain presence of harmful recessive alleles in the population
93
p=?
q=?
p=frequency of dominant allele
q=frequency of recessive allele
94
criteria for a population to be at equilibrium
1. large population
2. isolated from other populations
3. no net mutations
4. have random mating
5. have no natural selection
95
homology
similarity resulting from common ancestry
96
comparative anatomy
comparison of body structures between species
97
homologous structure
similar structure with different functions
98
vestigial structure
structure that does not have an apparent function
99
convergent evolution
populations evolving under similar environmental conditions may develop similar adaptions by coincidence
100
clade
group of organisms including the common ancestor
101
monophyletic taxon
single common ancestor and all descendents
102
paraphyletic taxon
single common ancestor excluding some descendents
103
polyphyletic taxon
multiple common ancestors and all descendents
104
evidence of common ancestry for all life
carry genetic code in DNA and RNA, share metabolic pathways
105
all eukaryotes have (5 things)
linear chromosomes, membrane bound organelles, introns in genes, endomembrane system, cytoskeleton
106
speciation
the origin of a new species
107
adaptive radiation
follows mass extinction, rapid diversification of a lineage
108
punctuated equilibrium
long periods of no change interrupted by episodes of rapid change
109
habitat isolation, behavioral isolation, temporal isolation, mechanical isolation, and gametic isolation are examples of...
prezygotic reproductive isolation
110
Reduced hybrid viability, Reduced hybrid fertility, and Hybrid breakdown are examples of...
post-zygotic reproductive barriers
111
allopatric speciation
a parent population is divided into 2 separate populations by a geographic barrier
112
sympatric speciation
change in the genome causes some individuals in a population to be reproductively isolated
113
114
Probiants
Primitive cells, collections of molecules surrounded by a simple membrane
115
RNA world hypothesis
RNA could have been the earliest genetic material
116
Endosymbiotic theory
Eukaryotic cells began when small cells began living inside larger cells
117
Evidence of endosymbiotic theory
Mitochondria + chloroplast have their own DNA + ribosomes,are enclosed in a membranes, and are self-replicating (they are semiautonomous)
118
Ribozymes
RNA capable of enzyme-like function (speed reactions)
