Quiz 3 Flashcards
1
Q
Pauling
A
chemical bonds, alpha helix (protein 2nd structure)
2
Q
Chargaff
A
discovered the nucleotide content of DNA (%G=%C, %T=%A)
3
Q
Wilkins
A
British biophysicist, worked on DNA structure
4
Q
Franklin
A
X-ray diffraction studies of DNA
5
Q
Watson and Crick
A
studied proteins at first, used pictures from Franklin, discovered the structure, double helix of DNA, made DNA models
6
Q
DNA structure
A
backbone of nucleotides- thymine, adenine, guanine, cytosine, connected by covalent bonds
- two strands connected by hydrogen bonds
- double helix
7
Q
RNA structure
A
- contains ribose sugar
- directly involved in making proteins
- contains uracil instead of thymine
- single strand
8
Q
Sequence hypothesis
A
DNARNA->Proteins
Replication, transcription, translation
9
Q
chromatin
A
structure of a chromosome consisting DNA wrapped around histone proteins
10
Q
nucleosome
A
histone protein with their encircling DNA
11
Q
replication
A
- process by which a cell makes copies of its DNA
- 2 strands of DNA unwind at many sites along the length of the molecule
- hydrogen bonds are broken by the enzyme helicase
- each parent strand serves as a template fro the assembly of a new DNA strand from nucleotides
- 2 stands (half old half new) of DNA are now present
12
Q
codon
A
set of 3 nucleotides of mRNA that codes for the placement of an amino acid during translation
13
Q
start codon
A
tells ribosome where the beginning of the gene is
14
Q
stop codon
A
tells the ribosome when to stop
15
Q
promoter sequence
A
specific sequences of DNA nucleotides that RNA polymerase uses to find a protein-coding region of DNA and to identify which of the two DNA strands is the coding strand
16
Q
terminator sequence
A
DNA sequences that indicate when RNA polymerase should finish making an RNA molecule
17
Q
anticodon
A
trio of bases in the tRNA that is involved in base-pairing
18
Q
gene
A
- section of DNA that codes fro a protein or pieces of RNA and determines traits
- able to replicate by directing the manufacture of copies of themselves
- can get mutated
- stores information that determines the characteristics of cells and organisms
- uses information to direct synthesis of proteins
19
Q
intron
A
sequences of mRNA that do not code for a protein
20
Q
exon
A
sequences of mRNA that codes for a protein
21
Q
mutation
A
any change in the DNA sequences of an organism
22
Q
transposon
A
a non protein coding DNA
23
Q
DNA polymerase
A
enzyme that connects nucleotides together
24
Q
RNA polymerase
A
enzyme that “reads” the sequence of DNA that indicate the base pairing rules to build the new RNA molecule
25
transcription
- process of using DNA as a template to synthesize RNA
- RNA polymerase "reads" the DNA and attaches to it and begins to build a new protein
- beings when the enzyme separates the two strands of DNA
- exposes the nitrogen bases so one strand can be "read"
26
translation (protein synthesis)
process of using the information in RNA to direct protein synthesis by attaching amino acids to one another
27
imitation
start codon, AUG, end of tRNA carries an amino acid
28
elongation
chain of amino acids is growing, every time the ribosome works through a series, a new amino acid is added
29
termination
chain of amino acids grow until stopped by a stop codon, protein detaches from the ribosome
30
mRNA
messenger RNAm carries the blueprint for making the necessary protein
31
rRNA
ribosomal RNA, involved in the assembly of proteins from amino acids
32
tRNA
transfer RNA, moves a specific amino acid into a ribosome to make a protein
33
chromosomal aberration
major change in DNA that can be observed at the level of the chromosome that can cause harm, especially during fetal development
34
deletion
broken piece of DNA becomes lost or destroyed before its reattached
35
inversion
occurs hen a chromosome is broken and a piece becomes reattached to its original chromosome, but flipped
36
translocation
one broken segment of DNA becomes integrated into a different chromosome
37
duplication
portion of a chromosome is replicated and attached to the original
38
point mutation
change in a single nucleotide of the DNA sequence
39
silent mutation
nucleotide change that results in either the placement of the same amino acid or a different amino acid, but does not change the function of a protein
40
missense mutation
causes the wrong amino acid to be used in making a protein
41
nonsense mutation
causes a ribosome to stop protein synthesis by introducing a stop codon early
42
frameshift
occurs when insertion or deletions cause the ribosome to read the wrong sets of 3 nucleotides
43
Base pairing rules
DNA- A=T, G=C
| RNA- A=U, G=C
44
genetic enginerering
manipulating DNA for our benefit
45
biotechnology
using organisms for our benefit
46
cloning
replicate (a fragment of DNA placed in an organism) so that there is enough to analyze or use in protein production
47
recombinant DNA
DNA that has been formed artificially by combining constituents from different organisms
48
gene mapping
a method used to identify the locus of a gene and the distances between genes
49
gene therapy
the translation of normal genes into cells in place of missing or defective ones to correct genetic disorders
50
DNA fingerprinting
the analysis of DNA from samples of body tissues or fluids, especially when conducted to identify individuals
51
gel electrophoresis
lab method used to separate mixtures of DNA, RNA, or proteins according to their size
52
plasmid
genetic structure in a cell that can replicate independently of the chromosomes
53
GMO
genetically modified organisms
54
importance of cell division
growth, development, repair, maintenance, reproduction
55
cytokinesis
the division of the cytoplasm of one cell into two new cells
56
interphase
stage of a cell cycle during which the cell engages in normal metabolic activities and prepares for the next cell division
57
G1 interphase
- cell gather nutrient sand other resources from the environment
- allows growth in volume and to carry out metabolic roles (ex: making RNA)
58
S interphase
DNA replication occurs
59
G2 interphase
- makes proteins to help with cell division
- membrane is still intact and nucleolus is sill visible
- centrioles replicate
60
prophase
- first stage of mitosis
- individual chromosomes become visible
- chromosomes condense, nuclear membrane disassembles, spindle and spindle fibers form, and nucleolus disappears
- animal cells spindle fibers attach to centrioles
- centrioles move to opposite ends of the cell
61
metaphase
- second stage of mitosis
- chromosomes align at the equatorial plane
- no nucleus present and each chromosomes contains 2 chromatids, but remain attached to centromeres
62
anaphase
- third stage of mitosis
- membrane is still absent and spindle extends pole to pole
- sister chromatids move toward opposite ends of the cell
- chromosomes begin to separate because enzymes digest portions of centromeres that holds the 2 chromosomes
63
telophase
- final stage of mitosis
- spindle fibers disassemble
- nuclear membrane reforms
- chromsomes uncoil and nucleolus reforms
64
cleavage furrow
indentation of the plasma membrane that pinches in toward the center of the cell eventually splitting it, only with animal cells
65
plant plate
forms at the center of the cell and grows out to the plasma membrane, marks the completion of mitosis and one round of cell division, only in plant cells
66
Lacks
- diagnosed with cervical cancer on 1/29/51 and a sample of her cells were taken for research
- those cells were used to develop polio vaccines, cancer research, virus infections, AIDS, effects of radiation, and cell cloning
67
differentiation
cell that has become a certain type
| ex: skin cells-some produce hair and some don't
68
centromere
sequence of bases at the site where sister chromosomes are attached
69
chromatid
1 of 2 parallel parts of chromosome
70
diploid cell
cell that has 2 complete sets of genetic information
71
haploid cell
cell that has 1 complete set of genetic information
72
gamete
general term for reproductive cells like egg and sperm
73
zygote
original single cell that results form an egg or sperm
74
homologous chromosomes
have the same order of genes along their DNA
75
synapsis
causes homologous chromosomes to move toward each other, which causes them to line up
76
crossing over
exchange of equivalent sections of DNA on homologous chromosomes
77
segregation
separation and movement of homologies chromosomes to the opposite poles of a cell
78
independent assortment
one pair of homologous chromosomes separate independently from each other
79
nondisjunction
occurs when homologous chromosomes do not separate during meiosis and may lead to the death of cells
80
Prophase 1
- chromosomes condense
- spindle fibers form
- nuclear membrane dissolves
- synapsis and crossing over occurs
81
Metaphase 1
- chromosomes align on equatorial plane as synapsed pairs
| - centromere attaches to a spindle fiber
82
Anaphase 1
- homologous chromsomes split
- chromosomes move toward cell's poles
- reduction occurs
- diploid to haploid cells
- segregation and independent assortment occur
83
Telophase 1
- spindle fibers disassemble
- chromosomes uncoil
- membrane reforms
- nucleoli reappear
84
Prophase 2
- individual chromosomes become visible
- chromosomes condense, nuclear membrane disassembles, spindle and spindle fibers form, and nucleolus disappears
- animal cells spindle fibers attach to centrioles
- centrioles move to opposite ends of the cell
- haploid cells
85
Metaphase 2
-chromosomes align again, moving as a separate unit
86
Anaphase 2
centromere divides, chromatids=daughter chromosomes
87
Telophase 2
cell returns to non dividing conditions
88
gene
- section of DNA that codes for a protein or pieces of RNA and determines traits
- able to replicate by directing the manufacture of copies of themselves
- can get mutated
- stores genetic information that determines the characteristics of cells and organisms
89
allele
specific version of a gene
90
locus
spot on chromosome where an allele is located
91
genome
a set of all the genes necessary to specify an organism's complete list of characteristics
92
genotype
catalog of genes of an organism, whether these genes are expressed or not
93
phenotype
physical characteristics
94
homozygous
describes a diploid organism that has 2 identical allele for a particular characteristic
95
heterozygous
describes a diploid organism that has 2 different alleles for a particular characteristic
96
dominant
an allele the expresses itself and masks the effects of the other alleles for that trait
97
recessive
an allele that, when present with its homologous, does not express itself and is masked by the effect of the other allele
98
incomplete dominance
occurs when the phenotype of a heterozygote is intermediate between the 2 homozygotes on a phenotypic gradient, the phenotypes appear to be "blended"
99
codominance
situation in which both alleles in a heterozygous organism express themselves
100
multiple alleles
several different alleles for a particular characteristic within a population, not just 2
101
polygenic
the concept that a number of different pairs of alleles may combine their efforts to determine a characteristic
102
pleinotropy
multiple effects that a gene may have on a phenotype of an organism
103
X-linked
the chromosome in a human female egg that is associated with the determination of sexual characteristics
104
probability
the chance that an even will happen, expressed as a % or fraction
105
population
a group of organisms of the same species located in the same place at the same time
106
biological species
the concept that species are distinguished from one another by their inability to interbreed
107
gene pool
all the genes of all the individuals of a species
108
allele frequency
a measure of how common a specific allele is, compared with other alleles for the same characteristic
109
genetic diversity
the degree to which individuals in a population possess alternative allele for characteristics
110
genetic drift
a change in gene frequency that is not the result of natural selection; this typical occurs in a small population
111
clone
exact copies of biological entities such as genes, organisms, or cells
112
monoculture
the agricultural practice of planting the same varieties of a species over large expanses of land
113
evolution
a change in the frequency of genetically determined characteristics within a population over time
114
selecting agent
factors that affect the probability that a gene will be passed down to the next generation
