Test 3 Flashcards
(131 cards)
1
Q
When DNA replicates the sister chromatids are held together at their centromeres by which of the following complex of proteins?
A
Cohesins
2
Q
Condensation of chromosomes continues throughout which phase?
A
Prophase
3
Q
What is a sequence of growth, replication, and division that produces new eukaryotic cells called?
A
Cell cycle
4
Q
During prometaphase, sister chromatids attach to the spindle by their _________, which are attached to the centromere region of each sister chromatid.
A
Kinetochores
5
Q
True or false: In a typical mammalian adult cell, the M phase takes up a large fraction of the entire cell cycle.
A
False
6
Q
During _______, which includes the G1, S and G2 phases of the cell cycle, the cell grows and chromosomes replicate in preparation for cell division.
A
interphase
7
Q
During ________ the chromosomes are aligned midway between the spindle poles.
A
metaphase
8
Q
Which is the first stage of mitosis?
A
prophase
9
Q
At the beginning of which phase does the centromeres of sister chromatids split apart allowing sister chromatids to separate from each other?
A
Anaphase
10
Q
During prometaphase, which protein complex on each sister chromatid attaches to the spindle?
A
Kinetochore
11
Q
When is the spindle apparatus broken down?
A
Telophase
12
Q
Typically, a dividing mammalian cell completes its cell cycle in about how many hours?
A
24hrs
13
Q
A cleavage furrow is typically formed during cytokinesis in _________ cells.
A
animal
14
Q
The pairs of sister chromatids align themselves in a single row along a plane half-way between the poles during which phase of mitosis?
A
Metaphase
15
Q
During cytokinesis in plants, what coats the newly formed cell plate?
A
Cellulose
16
Q
During the _________ of mitosis, the centromeres of sister chromatids split apart allowing sister chromatids to move away from each other.
A
Anaphase
17
Q
Cytokinesis involves the formation of a cleavage
________ in animal cells and a cell ________ in plant cells.
A
Furrow, Plate
18
Q
Condensation of chromosomes continues throughout which phase?
A
Prophase
19
Q
Two irreversible points in the cell cycle are replication of _________ material and ________ of sister chromatids.
A
Genetic (DNA) , seperation
20
Q
The ________ apparatus is broken down during telophase.
A
spindle
21
Q
Identify the type of protein encoded by the cdc2 gene.
A
Protein kinase
22
Q
Cytokinesis in animal cells involves the formation of a ________ furrow around the cell.
A
Cleavage
23
Q
During cytokinesis in plants, the newly formed cell plate is coated with ________ to create two new cell walls. At this point the space between the two daughter cells is called the middle _________.
A
cellulose; lamella
24
Q
The __ enzymes control progression through the checkpoints in the cell cycle.
A
Cdk
25
In which of the following cells does cytokinesis involve the formation of a cell plate?
Plant cells
26
If necessary (e.g., if DNA is damaged), the cell cycle can be arrested at specific points called
checkpoints
27
MPF is composed of two parts: a cyclin component and a __________ component.
kinase
28
What enzymes control the progression of cells through the cell cycle checkpoints?
Cdks
29
Cdks are enzymes which regulate proteins within the cell cycle via __.
phosphorylation
30
The cell _______ of multicellular eukaryotes is regulated by Cdks and external signals.
cycle
31
________ is a term to describe cells growing out of control.
Cancer
32
The first tumor-suppressor gene discovered as the cause of which of the following?
Familial cancer retinoblastoma
33
The cell cycle of multicellular eukaryotes is regulated by several ______ and many different ________
signals.
Cdks; external
34
A _________ is a cluster of cells that have lost control of their growing.
Tumor
35
Name the two distinct classes of cancer causing genes: __________ and ___________ genes.
oncogenes; tumor-suppressor
36
Eukaryotes that reproduce through _______ reproduction require two cells to contribute genetic material for the production of the next generation.
sexual
37
When two haploid gametes unite, they create a diploid cell called a(n) ______.
Zygote
38
Gametes are haploid. Haploid means that the cells contain how many sets of chromosomes?
One
39
Which process is responsible for the production of the adult body of an animal from a zygote?
Mitosis
40
How many rounds of cell division are required for meiosis?
2
41
Typically, how many cells contribute genetic material during sexual reproduction?
2
42
During meiosis, homologous chromosomes become closely associated in the process of pairing, or ______.
synapis
43
A zygote is created when two haploid cells, called
| _____, fuse.
gametes
44
An organism is diploid when its cells carry which of the following?
Two sets of chromosomes
45
In meiosis, when does DNA replication occur?
Before meiosis I only
46
What type of division (meiosis or mitosis) does the diploid zygote of an animal have to go through (usually many times) in order to give rise to all of the cells in the adult body?
Mitosis
47
In _________ I of meiosis, the replicated chromosomes condense, the homologous chromosomes form bivalents, and crossing over occurs.
Prophase
48
In sexually reproducing organisms, which type(s) of cell division requires two sequential rounds of division?
meiosis
49
Synapsis (or pairing) of homologous chromosomes occurs during which process?
meiosis
50
List the phases of Meiosis in order
Prophase 1
Metaphase 1
Anaphase 1
Telaphase 1
51
During______ I of meiosis, the homologues are pulled toward opposite poles of the cell.
Anaphase
52
Meiosis has how many rounds of DNA replication?
1
53
During which stage of meiosis do synapsis and crossing over occur?
Prophase 1
54
At this stage of meiosis I, the sister chromatids have reached their respective poles, and they then decondense.
Telephase
55
How many rounds of cell division are required for meiosis?
2
56
During anaphase I of meiosis I, which of the following describes the homologues?
They are segregated.
57
When meiosis occurs without recombination, which of the following has occurred?
Achiasmate segregation
58
In meiosis, when does DNA replication occur?
Before meiosis I only
59
In meiosis, when does DNA replication occur?
Before meiosis I only
60
The sister chromatids found in the daughter nuclei at the end of telophase I are not identical to each other due to which of the following?
crossing over
61
In sexually reproducing organisms, which type(s) of cell division requires two sequential rounds of division?
Meiosis
62
When chromosomes do not sort properly during cell division this is referred to as______.
nondisjument
63
Of the following choices, which is a similarity between mitosis and meiosis?
The number of chromosomes in the parent cell
64
When meiosis proceeds without recombination, this is referred to as _________ segregation.
achiasmate
65
In yeast, the Rec8 protein replaces the Scc1 protein in the cohesin complex during meiosis. Why is this important?
This allows the sister chromatids to stay together during meiosis I
66
When a cell undergoes meiosis, 4 daughter cells are produced. In terms of the number of chromosomes, each daughter cell contains a __________ nucleus.
haploid
67
Sister chromatid cohesion is maintained during which process?
Meiosis 1
68
At this stage of meiosis I, the sister chromatids have reached their respective poles, and they then decondense.
telephase
69
The _______ of sister chromatids are attached to the same pole during meiosis I and to opposite poles during meiosis II.
Kineochores
70
The term _______ refers to an event in which the chromosomes do not sort properly during cell division.
nondisjunction
71
DNA replication is suppressed prior to which cellular event?
Meiosis II
72
Which of the following is a distinctive feature of meiosis?
Meiosis includes a cell division that is not preceded by DNA duplication.
73
Which of the following is a meiosis specific cohesin protein in yeast?
Rec8
74
Which of the following must occur during anaphase I?
Meiosis specific cohesins must be removed from chromosome arms, but not from sister centromeres.
75
The four daughter cells produced by meiosis are
not genetically identical to each other
76
During meiosis I the sister kinetochores are attached to
the same pole
77
During meiosis I the sister kinetochores are attached to
the same pole
78
DNA replication should occur
Before meiosis I
| Before mitosis
79
A unique event in meiosis I is
homologous pairing
80
In yeast, the Rec8 protein replaces the Scc1 protein in the cohesin complex during meiosis. Why is this important?
This allows the sister chromatids to stay together during meiosis I.
81
Which type(s) of cellular division produce(s) cells that are not genetically identical to the mother cell?
Meiosis
82
Which type(s) of cellular division produce(s) cells that are not genetically identical to the mother cell?
Meiosis
83
DNA replication is suppressed prior to which cellular event?
Meiosis II
84
Prior to the work of Mendel, inheritance was viewed as resulting from
blending of traits from an offspring's parents.
85
A hybridization experiment involves mating
two individuals with different characteristics to each other
86
Which of the following plants was the main organism for Mendel's genetic experiments?
pea plant
87
Which of following crosses is crossing two variations of a single trait?
Monohybrid cross
88
In pea plants, the allele T encodes for tall plants, while the allele t encodes for dwarf plants. If a true-breeding tall pea plant is crossed with a true-breeding dwarf pea plant what are the expected genotypes of the offspring?
All Tt
89
Prior to the 20th century, the two main ideas that provided the basis for most thinking about heredity were_______
heredity occurs within species
| traits are transmitted directly from parents to offspring
90
In Mendel's experiments, he observed a 3:1 ratio between dominant and recessive traits in
the F2 generation of monohybrid crosses.
91
What type of experiment involves mating two individuals with different characteristics to each other? One individual provides females gametes, while the other provides male gametes.
Hybridization
92
When performing a monohybrid cross, Mendel noticed that not all individuals in the F2 generation were true breeding. What proportion were not?
1/2 of the F2 individuals exhibiting the dominant form were not true breeding.
93
Which of these are not reasons that Mendel chose to study the garden pea:
Long generation time
| They were inexpensive to buy
94
Which of the following is an example of a monohybrid cross?
White and purple flowers
95
Which of the following is NOT a component of Mendel's five-element model (please note that the answers use the modern term gene instead of factor)?
the two alleles are usually the same
96
The trait for round (R) peas is dominant over the trait wrinkled (r) peas. What would happen if true-breeding round peas are crossed with true-breeding wrinkled peas?
All offspring will have round peas.
97
What was the ratio that Mendel observed between dominant and recessive traits in the F2 offspring of a monohybrid cross?
3 dominant:1 recessive
98
A 3:1 phenotypic ratio in the F2 generation of a monohybrid cross represents this genotypic ratio:
1:2:1
99
Choose the 4 reasons that contributed to Mendel selecting the garden pea as his experimental subject.
Earlier investigators had produced hybrid peas.
Garden peas can self-fertilize.
There were a large number of pure varieties.
The garden pea had a relatively short generation time.
100
Choose statements that correctly refer to components of Mendel's five-element model (please note that the answers use the modern term gene instead of factor).
The presence of an allele doesn't ensure that it will be expressed.
Parents transmit genes to offspring.
The two alleles remain discrete.
Alternative forms of genes are called alleles.
101
A(n) ________ square can be used to predict the outcome of a simple genetic cross.
Punnett
102
Which of the following is NOT a component of Mendel's five-element model (please note that the answers use the modern term gene instead of factor)?
the two alleles are usually the same
103
The trait for round (R) peas is dominant over the trait wrinkled (r) peas. What would happen if true-breeding round peas are crossed with true-breeding wrinkled peas?
All offspring will have round peas.
104
A Punnett square has rows and columns which represent gametes made by males and females. At the intersection of each row and column we combine the corresponding gametes to produce the genotype of a potential _________.
offspring
105
True or false: Mendel found that plants exhibiting the recessive trait were usually not true-breeding.
False
106
What type of cross follows the simultaneous inheritance of two different traits?
Dihybrid cross
107
One of the parents in a dihybrid cross has the genotype AABb. How many types of gametes can this parent produce?
2
108
A Punnett square for a single trait should be set up as a ______ square (Not counting the squares for parental gametes).
2x2
109
A(n) ________ cross follows the simultaneous inheritance of two different characters.
2-factor
110
In a heterozygous individual, the probability of a recessive allele being present in a gamete is
0.5
111
A parent with a genotype of RrYy can produce which of the following gametes?
Ry
ry
RY
rY
112
In the cross of Pp x Pp four outcomes are possible: PP, Pp, pP, and pp. The probability of being heterozygous is ________.
1/2
113
Mendel's observations supported the independent __________ hypothesis.
assortment
114
In a homozygous recessive individual the probability of the dominant allele being present is
0
115
To calculate the probability that if a woman has four children, they will all be girls, you should use the
product rule
116
If the offspring from a testcross contain only heterozygotes, the genotype of the unknown parent must be
homozygous dominant
117
In order for Mendel's simple ratios to hold true, the following assumption must be made:
that the traits are inherited independently
118
Continuous phenotypic variation results from
polygenic inheritance and independent segregation of genes
119
In terms of probabilities, the cross of a tall yellow seeded pea plant (TTYy) with a tall green seeded pea plant (Ttyy) is equivalent to which two monohybrid crosses?
TT x Tt and Yy x yy
120
The inheritance patterns of many traits are (more or less) complex than simple Mendelian patterns.
More
121
When continuous traits are graphed in the form of a histogram with the phenotype on the X-axis, and the frequency of individuals with that phenotype on the Y-axis, a _________-shaped curve results.
bell
122
When continuous traits are graphed in the form of a histogram with the phenotype on the X-axis, and the frequency of individuals with that phenotype on the Y-axis, a _________-shaped curve results.
bell
123
Sickle cell anemia is caused by a __________
| allele because this mutation has more than one effect on the phenotype.
pleiotropic
124
True or false: Due to the diploid nature of eukaryotic cells, a gene can never have more than two alleles in a population of organisms.
False
125
Which of these blood phenotypes is NOT properly matched with the sugar exhibited on red blood cells?
Type O - have galactosamine and galactose
126
Examples of environmental influences on phenotype include
the pattern of coat color in Himalayan rabbits
| the pattern of coat color in Siamese cats
127
Continuous phenotypic variation results from
polygenic inheritance and independent segregation of genes
128
When the interaction of genes alters genetic ratios, this is called ________.
epistasis
129
An allele that has more than one effect on phenotype is called
pleiotropic.
130
Which of the following are examples of environmental effects on phenotype?
The amount of sunlight experienced by a sunflower affects the number of seeds produced.
The number of seeds eaten by a bird affects its weight.
131
In a certain plant, fruit color is affected by an epistatic interaction between two genes. The fruit is red in the presence of at least one dominant allele of either or both gene A or gene B, and white when there are no dominant alleles present. What proportion of the offspring of a cross of AaBb x AaBb plants is expected to be red?
15/16
