Quan Exam 2 Flashcards
1
Q
genetics is the study of ____; it involves the study of ___, individuals, their offspring, and the ____ within which organisms live.
A
heredity; cells; populations
2
Q
geneticists investigate all forms of ____ and the nature of the underlying ____ of such characteristics
A
inherited variation; genetic basis
3
Q
a ____ is constructed by mating individuals from two parent strains, each of which exhibits one of the two contrasting forms of the character under study
A
monohybrid cross
4
Q
the physical appearance of a trait is called the ____ of the individual; the ____ properties of an organism that are genetically controlled
A
phenotype; observable
5
Q
the specific allele or genetic constitution of an organism
A
genotype
6
Q
individuals that result from the self fertilization of the F1 generation are called the ____
A
F2 generation (by an F1 cross)
7
Q
mendel’s postulates
A
- principles of paired factors - unit factors in pairs
- Principle of dominance- dominance/recessiveness
- law of segregation (purity of gametes); mendel’s first law of inheritance
- law of independent assortment (Mendel’s second law of inheritance)
8
Q
genetic characters are controlled by _____ that exist in pairs in individual organisms
A
unit factors
9
Q
when two unlike unit factors responsible for a single character are present in a single individual, one unit factor is said to be ____ to the other, which is said to be ____
A
dominant; recessive
10
Q
during the formation of gametes, the paired unit factors ____ or ____ randomly so that each gamete receives one or the other with equal liklihood
A
separate; segregate
11
Q
during gamete formation, segregating pairs of unit factors ____ ____ of each other
A
assort independently
12
Q
a diagram used to predict an outcome of a particular cross or breeding experiment
A
punnett square
13
Q
punnett squares used by biologists to determine the probability of an offspring to have a particular ____
A
genotype
14
Q
a ____ is constructed by mating individuals from two parent strains; there are 2 pairs of contrasting forms of character under study
A
dihybid cross
15
Q
a sequence of DNA bases containing biologically useful information (unit factor)
A
gene
16
Q
specific location or position of a gene on a chromosome
A
gene locus
17
Q
alternative form of a gene (unlike unit factor)
A
allele
18
Q
chromosome pairs of approx. the same length, centromere positioning, and staining pattern
A
homologues
19
Q
homologues are for genes with the same corresponding gene ____
A
loci
20
Q
the first division in meiosis separates ____
A
homologous chromosomes
21
Q
the second division in meiosis separates _____
A
sister chromatids
22
Q
haploid (1n) is the result of ____ and has one set of chromosomes aka gametes
A
meiosis
23
Q
combining the gene products from the two alternative alleles produces an intermediate phenotype
A
incomplete or partial dominance
24
Q
in a heterozygous gene, both alleles are dominant and expressed without blending
A
co-dominance
25
the existence of two or more discontinuous, segregating phenotypes in a population
polymorphism
26
the phenomenon of masking or modifying the effects of one gene pair by the expression of another gene pair
epistasis
27
expression, or the lack of expression of certain genes can affect the survival of an organism
lethal allele
28
the gene that determines a specific character is located on a sex chromosome; genes on sex chromosomes will NOT distribute evenly
sex linkage
29
during meiosis, a limited number of ____ events occur randomly between homologous chromosomes
crossover
30
the closer two loci reside along the axis of the chromosome, the ____ likely it is that any crossover event will occur between them
less
31
the ____ of a genetic disorder is the proportion of individuals with the at-risk genotype who actually express the trait
penetrance
32
trait is expressed in 100% of persons with that genotype
complete penetrance
33
an enzyme that cuts DNA at or near specific recognition nucleotide sequences known as restriction sites
restriction enzymes
34
in a ____ molecule, both strands terminate in a base pair
blunt-ended
35
____ or ____ ends are created by various overhangs (a stretch of unpaired nucleotides in the end of a DNA molecule)
adhesive; sticky
36
a rapid and sensitive method for radioactively, or non-isotropically, labeling DNA fragments, and is useful for visualizing small amounts of DNA
end-labeling
37
a type of hybridization that uses labeled complimentary DNA, RNA, or modified nucleic acid strands (i.e. probe) to localize a specific DNA or RNA sequence in a portion or section of a tissue
in situ hybridization
38
circular bacterial DNA
plasmid
39
the enzyme that has ligating ability of nucleotides
ligase
40
a collection of the total genomic DNA from a single organism
genomic DNA library
41
in a genomic DNA library, the DNA is stored in a population of identical ____, each containing a different ____ of DNA
vectors; insert
42
cDNA is ____ DNA that is synthesized from a ____ template in a reaction catalyzed by the enzyme _____
double-stranded; single-stranded RNA; reverse transcriptase
43
a method of investigating the sequence of specificity of DNA binding proteins in vitro
DNA foot printing
44
DNA foot printing can be used to study ____ interactions both outside and within cells
protein-DNA
45
a molecular biology method that is used to make specific and intentional changes to the DNA sequence of a gene and any gene products
site-directed mutagenesis
46
a genetic technique that uses homologous recombination to change an endogenous gene; also a replacement strategy based on homologous recombination
gene targeting
47
gene targeting can be used to ____ a gene, remove ____, ___ a gene, and introduce ____
delete; exons; add; point mutation
48
3 phases of transcription
initiation, elongation, and termination
49
a region of DNA that initiates transcription
promoter
50
the template strand of DNA has the ____ on the DNA strand
anticodons
51
the coding strand of DNA is the ____ that has the ____ used in translation
mRNA; codons
52
the sigma factor enables specific binding of ____ to ____ and is needed for ____
RNA polymerase; gene promoters; RNA synthesis
53
the calculated order of most frequent resides, either nucleotide or amino acid, found at each position in a sequence alignment
consensus regions in a promoter
54
two types of transcription termination in prokaryotes
1. rho dependent
| 2. rho independent
55
rho-dependent termination is controlled by the rho protein, which tracks along behind the ____ on the growing ____ chain
polymerase; mRNA
56
near the end of the gene, the polymerase encounters a run of ____ on the _____ and it stalls; as a result, the rho protein collides with the polymerase; the interaction with rho releases the ____ from the ____ bubble
G nucleotides; DNA template
| mRNA; transcription
57
rho-independent termination is controlled by specific sequences in the ____
DNA template strand
58
as the polymerase nears the end of the gene being transcribed, it encounters a region rich in ____ nucleotides. The mRNA folds back on itself and the complementary ____ nucleotides bind together
C-G
59
the result is a stable ___ that causes the polymerase to stall as soon as it begins to transcribe a region rich in ___ nucleotides; the complementary ____ region of the mRNA transcript only forms a weak interaction with the template DNA
hairpin; A-T; U-A
60
this, coupled with the stalled polymerase, induces enough instability for the ____ to break away and liberate the new ____
core enzyme; mRNA transcript
61
mRNA transcription that has genetic information in it that will create many proteins
polycistronic transcription
62
mRNA transcription that contains only the genetic information for 1 protein
monocistronic transcription
63
what does an operon consist of?
three adjacent structural genes, a promoter, a terminator, and an operator
64
a substance that acts on an operon to inhibit mRNA synthesis
repressor
65
a segment of DNA to which a transcription factor binds to regulate gene expression
operator
66
the lac operon is regulated by several factors including the availability of ____ and ____
glucose; lactose
67
lac operon can be activated by _____
allolactose
68
lactose binds to the ____ of lac operon and prevents it from repressing ____
repressor protein; gene transcription
69
components of chromatin
protein, RNA, and DNA
70
the most tightly packed DNA, it is transcriptionally silent, and differs from cell to cell
heterochromatin
71
de-condensed DNA that is transcriptionally active
euchromatin
72
____ is chromatin that is decondensed and can be ____; ____ is condensed and cannot be ____
euchromatin is decondensed and can be transcribed
| heterochromatin is condensed and cannot be transcribed
73
which polymerase transcribes mRNA?
polymerase 2
74
there are ___ general transcription factors that bind to all genes and there are _____ that will only bind to certain genes
5; gene-specific transcription factors
75
_____ are needed to bind pol 2 to the promoter
general transcription factors
76
_____ is the first transcription factor to bind to DNA
TBP (transcription binding protein)
77
location of enhancers
upstream, downstream, or in reverse orientation (last one is not natural and must be engineered)
78
____ limit the distance that enhancers operate; these proteins ___ the gene from outside effects
insulators; buffer
79
insulators prevent the ___ region from acting outside the ____ and prevent the spread of _____
control; domain; heterochromatin
80
an independently folded protein domain that contains at least one structural motif that recognizes double- or single-stranded DNA
DNA binding domain
81
DNA binding domains include ____ and _____
zinc finger proteins; leucine-zipper proteins
82
3 types of RNA processing
1. 5' capping
2. addition of the poly A tail (3' polyadenylation)
3. splicing of introns (RNA splicing)
83
polyadenylation involves lots of ____ added at the ___ end
adenosines; 3'
84
splicing of an RNA molecule:
- cleavage at the 5' splice site
- formation of a lariat like intermediate
- cleavage at the 3' splice site
- exons are ligated
85
how cells communicate with eachother
intercellular signaling
86
signaling within a cell
intracellular signaling
87
an extracellular signaling molecule binds to a ____ which activates ____ that can interact with ____
receptor protein; intracellular signaling proteins; target proteins
88
target proteins can have an effect on ____, alter ____, and alter ____ or _____
cell metabolism; gene expression; cell shape; movement
89
location of receptors
cell surface receptors and intracellular receptors
90
different types of intercellular signaling
contact dependent, paracrine, synaptic, and endocrine
91
can one signaling molecule perform multiple functions?
yes
92
signaling through cascade of intermediate signaling complexes happens through a series of ____ reactions which are initiated by a ____ or ____ acting on a receptor
chemical; stimulus; first messenger
93
signaling is transduced to the cell interior through ____ (which ____ the initial signal) and ultimately to _____, resulting in a cell response to the initial stimulus
second messengers; amplify; effector molecules
94
_____ and ____ have extracellular ligand binding domains and cytoplasmic catalytic domains
intrinsic tyrosine kinase receptors; intrinsic serine kinase receptors
95
ion channel-linked receptors; there are 5
ionotropic receptors
96
____ are very important in muscle contraction
nicotinic acetylcholine receptors (nAChRs)
97
2 types of metabotropic receptors
muscarinic acetylcholine receptors and beta-adrenergic receptors
98
receptor inactivation
- receptor sequestration
- receptor down regulation
- receptor inactivation
- production of inhibitory protein
99
types of G protein coupled receptors:
Alpha S, Alpha I, and Alpha Q
100
alpha S stimulates ____
adenylyl cyclase
101
Alpha I inhibits ____
adenylyl cyclase
102
Alpha Q activates ____
phospholipase C (PLC)
103
in dissociation of G protein subunits, the ____ will deactivate from the ____when activated/phosphorylated and can then interact with whatever next molecule in a sequence
alpha unit; beta gamma unit
104
____ dissociates when activated by ____, a small molecule that plays a key role in the regulation of intracellular signal transduction
protein kinase A; cAMP
105
cAMP is derived from ____ by the catalytic action of a signaling enzyme ____
ATP; adenylyl cyclase
106
protein kinase A phosphorylates something and ____ removes a phosphate
protein phosphatase-1
107
cAMP transduces its effects on ____ interconversion by regulating a key signaling enzyme, _____
glycogen-glucose-1-phosphate; protein kinase A (PKA)
108
PKA phosphorylates target proteins on ____ and ____ residues
serine; threonine
109
a calcium channel that stimulates intracellular calcium mobilization
IP3
110
activates protein kinase C
DAG
111
____ is an activating cofactor for PKC; in the absence of ___, PKC activity will be repressed
Ca++
112
enzyme-linked receptors:
- insulin
- insulin-like growth factors (IGFs)
- nerve growth factor (NGF)
- brain derived neurotrophic factor (BDNF)
- epidermal growth factor (EGF)
- platelet derived growth factor (PDGF)
113
enzyme-linked receptors do not use ____ and are specifically used in ____
G-proteins; cell growth
114
receptor dimerization: in _____, a signal molecule will interact and cause _____
receptor tyrosine kinase (RTK); autophosphorylation
115
in receptor dimerization, the two domains in the ____ will come together, inducing ____ of the other domain
receptor tyrosine kinase (RTK); phosphorylation (autophosphorylation)
116
Ras are small ____ involved in ____
G-proteins; cell proliferation
117
Ras are ____, they have ___ dependent switches, and they activate ____
membrane bound; GTP; MAP kinases
118
the phosphorylation cascade results in a change in ____ or ____
gene expression; protein activity
119
____ use the NF-kB signaling pathway; this pathway starts with a ____ and eventually NF-kB translocates to the ____
cytokines; TNF-alpha (tumor necrosis factor); nucleus
120
in the nucleus, NF-kB binds with a ____, then the cell can transcribe _____
coactivator; target NF-kB genes
121
start codon
AUG / methionine; signals the start of protein synthesis
122
this will be dictated by the start codon, and each successive triplet will be read in register until a stop codon is reached
reading frame
123
transfer RNA is a ____ shaped structure with the codon on the "middle leaf" that will signal a ____
cloverleaf; amino acid
124
amino-acyl tRNA is an enzyme that catalyzes the formation of an ____ bond, linking the ____ of the adenosine nucleotide of the tRNA to the ____ group of the amino acid (A site inside the ribosome)
ester; 3' hydroxyl group; carboxyl
125
stop codons
UAA, UAG, UGA
| signal the end of protein synthesis and do not specify an amino acid
126
____ are used to facilitate protein folding
molecular chaperones
127
cellular machinery for protein turnover; a multicatalytic complex designed for degradation of cytosolic proteins
proteasome
128
targets proteins to the proteasome for degradation
ubiquitin
