Bio Midterm 1 Flashcards
(110 cards)
1
Q
DNA is…
A
semiconservative
2
Q
DNA has a ___________ backbone
A
sugar-phosphate
3
Q
base pairs on DNA are joined by
A
hydrogen bonds
4
Q
the sugar-phosphate backbone is joined by
A
covalent phosphodiester bonds
5
Q
A:T have ____ hydrogen bonds
A
2
6
Q
C:G have ______ hydrogen bonds
A
3
7
Q
A:
A
adenine
8
Q
T:
A
thymine
9
Q
C:
A
cytosine
10
Q
G:
A
guanine
11
Q
chromatin is…
A
fibers of DNA
12
Q
a chromatid is…
A
DNA wrapped around proteins called histones and nucleosomes
13
Q
a chromosome is…
A
two sister chromatids attached by a centromere
14
Q
homologous
A
having the same information
15
Q
a chromosome is made up of
A
2 homologous chromatids
16
Q
sex cells are…
A
haploid
17
Q
Mitosis phases
A
PMATC
18
Q
Prophase major developments:
A
centrioles appear, nuclear envelope dissolves, chromosomes appear
19
Q
Metaphase major developments:
A
centrioles produce spindle fibers, spindles push chromosomes to middle, chromosomes line up along metaphase plate
20
Q
Anaphase major developments:
A
chromosomes are broken into chromatids, chromatids move to opposite sides, each side gets one homologous chromatid
21
Q
Telophase major developments:
A
nucleus reforms, cell membrane pinches in, still sharing cytosol
22
Q
chromatids “move” because…
A
kinetochores in the centromere destroys spindle fibers
23
Q
Cytokinesis:
A
cell membrane separates forming 2 identical cells
24
Q
organism
A
a living entity made up of cells
25
theory
an explanation for a very broad class of observed phenomena that is supported by a wide body of evidence
26
experiments
allow researchers to test the effect of a single, well-defined factor on a particular phenomenon
27
hypothesis
a statement that can be tested by scientific research
28
control
checks for factors that might influence the outcome of the experiment
29
the experimental conditions must be...
as constant as possible
30
x-axis
independent variable
31
y-axis
dependent variable
32
scatterplots
continuous data
33
bar charts
discontinuous data/categories
34
histograms
show frequencies in populations
35
standard error
indicates the uncertainty in a calculated mean
36
standard deviation
an estimate of the variability of the population that the sample was taken from
37
p-value
probability of getting various values of the test statistic if the null hypothesis is correct
38
a difference among treatment groups is statistically significant if...
there is less than a 5% probability of observing it by chance
39
artificial selection
manipulating the composition of the population by selecting individuals with desirable traits to reproduce
40
natural selection
individuals with certain heritable traits produce more offspring than do individuals without these traits
41
evolution by natural selection is a change in...
allele frequencies in a population
42
evolution by natural selection occurs when heritable variation leads to...
differential reproductive success
43
biological fitness
the ability of an individual to produce surviving, fertile offspring relative to that ability in other individuals in the population
44
Adaptation
a heritable trait that increases the fitness of an individual in a particular environment relative to individuals lacking the trait
45
adaptation increases
fitness
46
only ______ can evolve
populations
47
Polygenic
many genes that exert a relatively small effect influence the trait
48
heredity
transmission of traits from parent to offspring
49
trait
any observable characteristic of an individual ranging from outward appearance to molecular characteristics
50
Model organism
a species that is used for research because it is easy to work with and conclusions drawn from studying it may apply to many other species
51
polymorphic trait
when one trait appears commonly in two or more different forms
52
phenotype
observable traits in an individual
53
pure line
individuals that produce offspring identical to the parents when they are crossed to another member of the same pure-line population or self-fertilized
54
hybrids
offspring from matings between the true-breeding parents that differ in one or more traits
55
parental generation
individuals used in initial cross
56
F1
first filial, progeny of parental generation
57
F2
second filial, progeny of f1
58
Monohybrid cross
a cross that produces a hybrid for a single trait
59
reciprocal cross
a set of matings in which the mother's phenotype in the initial cross is the father's phenotype in a subsequent cross
60
Particulate inheritance
hereditary determinants maintain their integrity from generation to generation and act as discrete, unchanging particles
61
gene
hereditary determinant of a trait
62
alleles
different versions of the same gene
63
genotype
the combination of alleles found in an individual
64
principle of segregation
two members of each gene pair must segregate into different gamete cells during the formation of eggs and sperm
65
the principle of segregation occurs during...
anaphase 1 and 2
66
homozygous
having two copies of the same allele
67
heterozygous
having two different alleles for the same gene
68
dihybrid
F1 individuals that are heterozygous for both genes
69
dihybrid cross
mating between dihybrids
70
principle of independent assortment
alleles of different genes are transmitted independently of one another, producing 4 phenotypes in a 9:3:3:1
71
the principle of independent assortment occurs during...
metaphase 1
72
testcross
a parent with a dominant phenotype but unknown genotype is crossed with a parent that contributes only recessive alleles
73
meiosis
nuclear division that leads to a halving of chromosome numbers and ultimately to the production of sperm and egg
74
karyotype
the number and types of chromosomes in a cell
75
haploid number
the number of distinct types of chromosomes
76
ploidy
the number of chromosome sets
77
zygote
the diploid cell that results from fertilization
78
wild type
common phenotype
79
mutation
a heritable change in a gene
80
mutant
an individual with an unusual phenotype due to a mutation
81
genetic locus
a particular position on a chromosome
82
linkage
the tendency of alleles of particular genes to be inherited together
83
recombinant chromosomes
generated during crossing over in prophase of meiosis 1
84
genetic map
a diagram showing the relative positions of genes along a particular chromosome
85
multiple allelism
the existence of more than two common alleles of the same gene
86
pleiotropic
a gene that influences many traits
87
gene interactions
when two or more genes influence a single trait
88
chromosome theory of inheritance
hereditary information is encoded in units called genes that are located on chromosomes
89
central dogma
DNA codes for RNA, RNA codes for proteins
90
ATP (adenosine triphosphate)
chemical energy
91
species
distinct, identifiable types of organisms
92
deoxyribonucleotides are...
monomers that polymerize to form DNA
93
3 nucleic acids code for...
1 amino acid
94
messenger RNA (mRNA)
single-stranded molecules of RNA carry information out of the nucleus from DNA to the site of the protein synthesis in the cytoplasm
95
RNA polymerase
an enzyme that uses DNA to synthesize a complementary RNA molecule
96
transcription
the process of using a DNA template to make an RNA molecule that has a base sequence complementary to the DNA
97
translation
the process of using the information in the base sequence of mRNA to synthesize proteins
98
mutation cause a change in...
genotype and create new alleles
99
point mutation
a mutation that alters the sequence of one or a short number of base pairs
100
Missense mutation
a point mutation that changes the identity of an amino acid in a protein
101
frameshift mutation
a mutation that shifts the reading frame
101
silent mutation
a point mutation that does not change the amino acid sequence of the gene product
102
nonsense mutation
occurs when a codon that specifies an amino acid is changed to a stop codon
103
3 categories of mutations:
beneficial, neutral, deleterious
104
aneuploidy
the addition/deletion of individual chromosomes
105
4 major structural changes after chromosome mutation:
deletion, inversion, duplication, translocation
106
overlapping standard error bars
cannot reject the null hypothesis
107
crossing over is the physical basis of...
recombination
108
structural region of a gene
codes for an RNA or protein that functions in the cell
109
regulatory region of a gene
is responsible for the expression of a gene
