Exam 3 Quiz Questions
In a monohybrid cross, when there are a pair of alternate forms of a trait, in which generation is one of the traits latent, or present but not expressed? Parental generation F3 F1 F2
F1
In a typical monohybrid cross, all of the offspring in which generation will exhibit a single trait without blending? Neither F1 or F2 F2 F1 Both F1 and F2
F1
This generation is produced when the F1 monohybrids self fertilize: F2 FSF P1 P2
F2
In Mendel's experiments, he observed a 3:1 ratio between dominant and recessive traits in testcrosses. the F2 generation of dihybrid crosses. the F2 generation of monohybrid crosses. the F1 generation of monohybrid crosses. the F1 generation of dihybrid crosses.
F2 monohybrid
Select all that apply Proto-oncogenes can code for which of the following proteins? Ras protein Growth-factor receptor p53 protein Src kinase Rb protein
Ras protein Growth-factor receptor Src kinase
The first tumor-suppressor gene identified was which of the following? p53 Ras Rb Src
Rb
During which phase of the cell cycle are the chromosomes replicated? M phase S phase G1 phase G2 phase
S
Replication of each chromosome and its centromere takes place during the ___________ phase to produce two complete DNA molecules.
S
Replication of each chromosome and its centromere takes place during which phase of the cell cycle? S G1 G2
S
During the _____________ phase of the cell cycle, the chromosomes are replicated.
S or synthesis
When meiosis proceeds without recombination, this is referred to as ____________ segregation.
achiasmate
When meiosis occurs without recombination, which of the following has occurred? Aneuploidy Non-independent assortment Achiasmate segregation
achiasmate segregation
The events of metaphase II include which of the following? Alignment of homologous pairs along the metaphase plate Synapsis and crossing over Cytokinesis Alignment of individual chromosomes along the metaphase plate
alignment of individual chromosomes
During the ______________ of mitosis, the centromeres of sister chromatids split apart allowing sister chromatids to move away from each other.
anaphase
The shortest stage of mitosis is
anaphase
Errors in meiosis can lead to gametes with the wrong number of chromosomes which are referred to as ________ gametes.
aneuploid
Which cell type has centrioles? Animal Plant Bacteria All eukaryotic cells
animal
In meiosis, when does DNA replication occur? Before meiosis II only Before meiosis I only Once before meiosis I and again before meiosis II
before meiosis I only
Prior to the work of Mendel, inheritance was viewed as resulting from the deletion of traits in offspring. traits skipping generations. blending of traits from an offspring's parents. inheritance directly from one parent and not the other.
blending of traits
_______________ is a term to describe cells growing out of control.
cancer
The ______ enzymes control progression through the checkpoints in the cell cycle. Multiple choice question. receptor tyrosine kinase Cdk microtubule DNA replication
cdk
What is a sequence of growth, replication, and division that produces new eukaryotic cells called? Cell division Cell cycle Cell growth Karyotyping
cell cycle
What usually occurs during the G1 phase? Cells are growing Cells are dividing Cells are replicating DNA
cells are growing
_____________ are cellular structures, typically found in animal cells, which are replicated during the G2 phase. They are positioned at the poles of the cell and participate in the movement of chromosomes during mitosis.
centrioles
The kinetochore microtubules are attached to kinetochores, which are bound to the __________________ , a point of constriction on the chromosome containing repeated DNA sequences.
centromere
If necessary (e.g., if DNA is damaged), the cell cycle can be arrested at specific points called phases. cyclins. CDKs. checkpoints.
checkpoints
The points where chromatids are held together following crossing over are called _____________.
chiasma
The points where chromatids are held together following crossing over are called...
chiasma
What is the name for the sites of crossing over in a chromosome? Chiasmata Centrosome Centromere Kinetochore
chiasmata
Cytokinesis in animal cells involves the formation of a _____________ furrow around the cell.
cleavage
The key event in anaphase is the removal of _________ proteins from the centromeres of sister chromatids. condensin histone cohesin SMC
cohesin
When DNA replicates the sister chromatids are held together at their centromeres by which of the following complex of proteins? Adhesins DNA polymerases Cohesins Condensin
cohesins
Mendel was able to produce hybrids in pea plant by using a technique called _________-pollination.
cross
Recombination nodules are structures that contain the enzymes needed for crossing over synapsis sister chromatid cohesion cytokinesis
crossing over
What involves a physical exchange of DNA segments between homologous chromosomes? Chiasma Crossing over Bivalent formation
crossing over
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? Synapsis Independent assortment Segregation Crossing over
crossing over In independent assortment chromosome in the homologous pair are oriented randomly towards the two poles of the cell, however, the sister chromatids of each chromosomes are not affected by that!
In multicellular eukaryotic organisms, the production of new cells follows a highly regulated sequence of growth, DNA replication, and division. This sequence is referred to as the cell _____________, which consists of the G1, S, G2, and M phases.
cycle
After completing mitosis, cells divide into two daughter cells. This phase of the cell cycle is called cleavage cytokinesis telophase G3
cytokinesis
A hybridization experiment involves mating two individuals with similar characteristics to each other two individuals with different characteristics to each other two individuals with identical characteristics to each other
different characteristics
In most animals, the ______ state of the life cycle is much larger than the ______ state of the life cycle. diploid; haploid meiotic; mitotic haploid; diploid triploid; diploid
diploid; haploid
The active domains of chromatin in a nondividing nucleus are called _______________.
euchromatin
During telophase, chromosomes uncoil to allow for gene ______________.
expression or transcription
True or false: A centromere is located at a random location along the length of a chromosome.
false. Each centromere occurs at a specific location along a chromosome.
True or false: The length of time required to complete the cell cycle is the same in all cell types.
false. The length of time required to complete the cell cycle varies among cell types.
The first tumor-suppressor gene discovered as the cause of which of the following? Prostate gland cancer Lung cancer Familial cancer retinoblastoma Familial breast cancer
familial cancer retinoblastoma
An individual's total set of alleles for a particular trait is called his/her...
genotype
Meiosis is the process by which ___________ cells are produced from a cell that was originally diploid.
haploid
When a cell undergoes meiosis, 4 daughter cells are produced. In terms of the number of chromosomes, each daughter cell contains a __________ nucleus.
haploid
Which of the following is one of the significant results of meiosis? It creates diploid gametes for sexual reproduction. It creates diploid cells that grow to become new individuals. It creates zygotes that grow to become new individuals. It creates haploid gametes for sexual reproduction.
haploid
The inactive domains of chromatin in a nondividing nucleus are referred to as...
heterochromatin
Which is not a characteristic of meiosis II? The resulting daughter cells are haploid The sorting event is similar to that of mitosis Sister chromatids are separated Homologous chromosome pairs are separated
homologous chromosome pairs are separated
A unique event in meiosis I is chromosome replication cytokinesis homologous pairing
homologous pairing
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. Random cross Self-cross Hybridization Reciprocal cross
hybridization
In anaphase I a pole may receive either the maternal or paternal homologue from each chromosome pair. This means that the genes on different chromosomes assort...
independently
In actively dividing cells, the G1, S, and G2 phases are collectively known as which of the following? Prophase Metaphase Interphase Anaphase
interphase
In an actively dividing eukaryotic cell, the G1, S, and G2 phases are collectively constitute the ____________.
interphase
MPF is composed of two parts: a cyclin component and a ________ component.
kinase
During anaphase A, chromosomes are pulled towards opposite poles as their ______________ microtubules become shorter.
kinetochore
The centromere serves as an attachment site for a group of proteins that form a disklike structure called which of the following? Kinetochore Centrosome Centriole
kinetochore
Which type of microtubules attach to and separate the chromosomes during cell division? The kinetochore microtubules The polar microtubules The astral microtubules
kinetochore
During prometaphase, sister chromatids attach to the spindle by their ______________, which are attached to the centromere region of each sister chromatid.
kinetochores
The ___________ of sister chromatids are attached to the same pole during meiosis I and to opposite poles during meiosis II.
kinetochores
During meiosis I, the ____________ of sister chromatids function as a unit, attaching to the same microtubule.
kinetochores or centromeres
Select all that apply Histone proteins have a positive charge due to an abundance of which of the following amino acids? Glycine Lysine Glutamic acid Arginine
lysine arginine
Synapsis (or pairing) of homologous chromosomes occurs during which process? Mitosis Meiosis Both meiosis and mitosis
meiosis
Which type(s) of cellular division produce(s) cells that are not genetically identical to the mother cell? Mitosis Meiosis Both meiosis and mitosis
meiosis
Sister chromatid cohesion is maintained during which process? Mitosis Meiosis II Meiosis I
meiosis I
During ______________ the chromosomes are aligned midway between the spindle poles.
metaphase
The pairs of sister chromatids align themselves in a single row along a plane half-way between the poles during which phase of mitosis? Telophase Metaphase Prometaphase Cytokinesis
metaphase
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
Which process is responsible for the production of the adult body of an animal from a zygote? Mitosis Fertilization Meiosis
mitosis A zygote is a single cell. In order to produce an adult animal that cell has to undergo many mitotic divisions. Meiosis will typically not occur until the animal is producing gametes.
During the five phases of ___________, the replicated genetic material is partitioned into ________ new nuclei.
mitosis two
A cross in which only a single trait is considered is called a(n) _________ cross or single factor cross.
monohybrid
A recombination _________ contains the enzymatic machinery necessary to break and rejoin chromatids of the homologous chromosomes.
nodule
Aneuploid gametes are produced by which of the following? Synapsis Nondisjunction during meiosis Errors in crossing over
nondisjunction during meiosis
During telophase, the nuclear envelope re-forms to produce two separate _________. chromosomes nuclei cells
nuclei Reassembly of the nuclear envelope results in two nuclei, not two cells. Two separate cells are formed during cytokinesis.
Gametes are haploid. Haploid means that the cells contain how many sets of chromosomes? Three One Two
one
In sexual reproduction in eukaryotes, each parent contributes one set of chromosomes to the offspring. half a set of chromosomes to the offspring. two sets of chromosomes to the offspring.
one set
In the monohybrid crosses performed by Mendel, the F1 plants always displayed ____. one trait a blending of two traits two traits
one trait
The _______ protein will stop the cell cycle if damaged DNA is detected to allow for repair of the damaged DNA. If the cell cannot be repaired, it will be directed to kill itself.
p53
Cdks are enzymes which regulate proteins within the cell cycle via.... phosphorylation ubiquitylation methylation degradation
phosphorylation
Which of the following produce a cell plate during cytokinesis? Animal cells Bacterial cells Plant cells
plant
Condensation of chromosomes continues throughout which phase? Prophase Telophase Metaphase
prophase
In __________ I of meiosis, the replicated chromosomes condense, the homologous chromosomes form bivalents, and crossing over occurs.
prophase
Which is the first stage of mitosis? Telophase Metaphase Prometaphase Prophase Anaphase
prophase
During which stage of meiosis do synapsis and crossing over occur? Prophase II Cytokinesis II Prophase I Metaphase I
prophase I
Chromatin is a complex with ~40% DNA and which of the following? ~60% Lipids ~60% Carbohydrates ~60% Glycolipids ~60% Protein
protein
Identify the type of protein encoded by the cdc2 gene. Isomerase Protein kinase Dehydrogenase
protein kinase
_________ _____________ are normal cellular genes that become oncogenic when mutated.
proto oncogenes
One reason that it is likely that no two human gametes will have the same combination of homologous chromosomes is due to which of the following? Random assortment of chromosomes Chromatid adhesion Cytokinesis in meiosis II
random assortment of chromosomes
The ______________ form of a trait is the one that is not expressed in the F1 generation of a monohybrid cross.
recessive
An example of a ___________ cross is using pollen from a green-seeded pea plant to fertilize a yellow-seeded pea plant and then using pollen from a yellow-seeded pea plant to fertilize a green-seeded pea plant.
reciprocal
When the alleles of genes that were formerly on separate homologues can be found on the same homologue which of the following has occurred? Cytokinesis has occurred Recombination has occurred Reductive division has occurred
recombination
During anaphase I of meiosis I, which of the following describes the homologues? They are segregated. They are decondensed. They are aligned. They are integrated.
segregated
Eukaryotes that reproduce through ___________ reproduction require two cells to contribute genetic material for the production of the next generation.
sexual
When reproduction is achieved through meiosis and subsequent fertilization, it is called ____________ reproduction.
sexual
The process that brings all four chromatids in a pair of homologues together in close association is called which of the following? Genetic recombination Sister chromatid cohesion Independent assortment
sister chromatid cohesion
During DNA replication the chromosomes contract and the identical halves are called ____________ ____________ .
sister chromatids
Anaphase of mitosis separates ______ while anaphase I of meiosis separates ______. homologues; sister chromatids sister chromatids; homologues chiasmata; sister chromatids
sister chromatids; homologues
Select all that apply The two types of gametes typically produced by multicellular eukaryotic organisms are sperm cells somatic cell testes egg cells
sperm and egg
Two centriole pairs establish a bridge of microtubules which form the __________ ____________ during prophase.
spindle apparatus
During meiosis, homologous chromosomes become closely associated in the process of pairing, or ____________.
synapsis
The association of homologous pairs guided by heterochromatin sequences is called which of the following? Synapsis Chiasmata Crossing over Reductive division
synapsis
During prophase I, all four chromatids of the two homologues become closely associated as a result of pairing, also known as _________ .
synapsis or pairing
The structure consisting of paired homologues along a lattice of proteins between them is called what? Kinetochore complex Crossing over Synaptonemal complex
synaptonemal complex
At this stage of meiosis I, the sister chromatids have reached their respective poles, and they then decondense. Metaphase Interphase Anaphase Telophase
telophase
During the stage of mitosis known as _____________ , gene expression resumes, as chromosomes uncoil.
telophase
When is the spindle apparatus broken down? Metaphase Anaphase Telophase Prophase
telophase
_____________ can be viewed as the stage of mitosis during which the changes made to the cell during prophase are reversed.
telophase
Which is the final phase of mitosis? Interphase Telophase Cytokinesis
telophase Mitosis only refers to the division of he nucleus. Cytokinesis is not part of mitosis.
During meiosis I the sister kinetochores are attached to opposite poles both poles the same pole
the same pole mitosis and meiosis II, attached to opposite poles
In human embryos, the condition characterized by the presence of an extra copy of any chromosome is called _____________, and the condition characterized by the absence of any chromosome is called _____________.
trisomy monosomy
Which term is used to refer to plant varieties in which offspring produced from self-fertilization remain uniform from one generation to the next. True-breeding False-breeding Self-breeding Same-breeding
true-breeding
A pea plant with green seeds is allowed to self hybridize. All of the resulting offspring plants produce green seeds as well. That plant is therefore considered to be a true-breeding plant a self-hybridizing plant a true-hybridizing plant a self-pollinating plant
true-breeding plant
A ____________ is a cluster of cells that have lost control of their growing.
tumor
The gene that encodes the p53 proteins is referred to as a(n) ________ _____________ gene.
tumor suppressor
_____________ ____________ genes are normal cellular genes that when mutated in both alleles the result might be cancer.
tumor suppressor
Typically, how many cells contribute genetic material during sexual reproduction? Four Two One Two or three, depending on the species
two
An organism is diploid when its cells carry which of the following? Four sets of chromosomes Six sets of chromosomes Two sets of chromosomes Three sets of chromosomes
two sets
When two haploid gametes unite, they create a diploid cell called a(n)
zygote
Meiosis has how many rounds of DNA replication?
1
Prior to the 20th century, the two main ideas that provided the basis for most thinking about heredity were (select all that apply) A. traits are transmitted directly from parents to offspring B. traits in offspring are different from parents C. heredity occurs within species
A and C
Select all that apply Which of the following are true statements regarding sexual reproduction? A. The offspring receives genetic material from two parents. B. Specialized somatic cells fuse during fertilization. C. Haploid cells are produced through meiosis. D. Gametes are always produced by mitosis.
A and C
Meiosis produces cells that are not identical to each other because of which of the following events (choose all that apply)? A. Random orientation of chromosomes in metaphase I B. Cytokinesis C. DNA replication D. Crossing over
A and D
Select all that apply Choose the reasons why the two homologous chromosomes do not separate from each other during the first meiotic division. A. They held together via sites of crossing over. B. They are permanently attached to each other. C. They are no longer homologous. D. They are held together by cohesin proteins.
A and D
Select all that apply Which of the statements below are true for chromosomes in eukaryotic cells? A. Diploid cells have two versions of each chromosome. B. Diploid cells have either a maternal homologue or a paternal homologue. C. Diploid cells have one version of each chromosome. D. Diploid cells have a maternal homologue and a paternal homologue.
A and D
An individual with genotype Aa can produce which gamete(s)? AA and aa Only A Only a A and a
A and a
Select all that apply Select the true statements about the life cycle of sexually reproducing organisms. A. Depending on the organism, either the haploid or the diploid stage can be dominant. B. In all sexually reproducing organisms, meiosis is required for the production of haploid cells. C. The haploid stage never involves mitosis. D. The life cycle of sexually reproducing organisms involves alternation between the haploid and diploid stage.
A, B, D
Choose statements that correctly refer to components of Mendel's five-element model A. The two alleles remain discrete. B. Each individual receives two copies of each gene from each parent. C. Parents transmit genes to offspring. D. Alternative forms of genes are called alleles. E. The two alleles are usually the same. F. The presence of an allele doesn't ensure that it will be expressed.
A, C, D, F
During anaphase B, microtubules slide past each other pulling the poles anchored to them away from the center of the cell. At the same time, chromosomes are also pulled apart because A. a different set of microtubules attaches the chromosomes to the poles. B. as the poles are pulled apart, the cytoplasm flows towards them, carrying the chromosomes with it. C. the same set of microtubules that pulls the poles also pulls the chromosomes.
A.
How can two pea plants be cross-fertilized? A. The male parts of flowers on one plants are removed and pollen from the other plant is introduced. B. One of the plants has to be male, while the other has to be female. C. The plants have to be grown together and their flowers must be left undisturbed. D. The plants have to be grown together but flowers must be removed from one of the plants.
A.
In a monohybrid cross, the F2 generation is produced by A. allowing the F1 generation to self-fertilize B. performing crosses of random individuals from the F1 generation C. crossing the F1 generation to one of the parents
A.
The four daughter cells produced by meiosis are A. not genetically identical to each other B. genetically identical in pairs, i.e. two are genetically identical, but different to the other two, which also genetically identical C. genetically identical to each other
A.
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 All TT 50% TT and 50% Tt 75% Tt and 25% tt All Tt
All Tt
Both somatic and germline cells are diploid. However, A. germline cells undergo mitosis, while somatic cells can undergo meiosis. B. somatic cells undergo mitosis, while germline cells can undergo meiosis. C. only somatic cells can undergo mitosis. D. only somatic cells can undergo both mitosis and meiosis.
B
During anaphase _____, microtubules slide past each other pulling the poles anchored to them, and the chromosomes attached to the poles, away from the center of the cell. A B
B
During meiosis I, the kinetochores of sister chromatids act as A. several units that direct crossing over events across the chromosome. B. a unit, to which polar microtubules attach. C. two separate structures, to which polar microtubules attach independently.
B
Identify the difference between metaphase of mitosis and metaphase of meiosis I. A. The chromosomes align in a different area of the cell. B. The chromosomes align singly in mitosis and in pairs in meiosis I. C. There is a different number of chromosomes in the cell.
B
The importance of the recombination machinery for proper disjunction of chromosomes is supported by the observation that A. meiotic nondisjunction leads to loss of DNA repair function B. loss of recombination function leads to higher levels of meiotic nondisjunction C. meiotic nondisjunction only occurs when recombination fails
B.
Which of the following accurately pairs animal somatic and germline cells with the number of chromosomes in them. A. Somatic cells:haploid; Germline cells:haploid B. Somatic cells:diploid; Germline cells:diploid C. Somatic cells:diploid; Germline cells:haploid D. Somatic cells:haploid; Germline cells:diploid
B. Germline cells are diploid. They give rise to haploid gametes. The gametes themselves are not considered germline cells!
Which of the following is NOT one of the three main stages that Mendel conducted his experiments in? Allowing plants to self-cross Allowing hybrid offspring to self-fertilize Back crosses between F1 and P individuals Reciprocal crosses between true-breeding varieties
Back crosses between F1 and P individuals
Meiosis II resembles mitosis because it involves the movement of which of the following? A. Paired homologues towards the poles of the cell B. Recombinant chromatids towards the poles of the cell C. Single chromatids towards the poles of the cell
C.
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? A. One quarter of the offspring will have round peas, and the other three quarters will have wrinkled peas. B. All offspring will have wrinkled peas. C. All offspring will have round peas. D. Half of the offspring will have round peas, and the other half will have wrinkled peas.
C.
Which of the following is a distinctive feature of meiosis? A. Sister chromatids stay together throughout both meiosis divisions. B. Meiosis results in the production of both diploid and haploid cells. C. Meiosis includes a cell division that is not preceded by DNA duplication.
C.
Which of the following is the key event in anaphase? A. Migration of chromosomes in a plane, located in the center of the cell A. Elongation of the cell's nonkinetochore microtubules C. Removal of cohesin proteins from the centromeres of sister chromatids
C.
Which of the following must occur during anaphase I? A. Meiosis specific cohesins must be removed both from chromosome arms and sister centromeres. B. Meiosis specific cohesins must be removed from sister centromeres, but not from chromosome arms. C. Meiosis specific cohesins must be removed from chromosome arms, but not from sister centromeres.
C.
Passage through which checkpoint is a commitment to cell division? G2/M checkpoint G1/S checkpoint Spindle checkpoint
G2/M
The chromosome number in the body cells of most eukaryotic species falls within which range? 10 and 30 10 and 50 1 and 10 1 and 50
10-50
A 3:1 phenotypic ratio in the F2 generation of a monohybrid cross represents this genotypic ratio: 1:1:2 2:1:1 1:2:1
1:2:1
What is the number of haploid chromosomes in humans? 46 69 92 23
23
A human gamete contains how many chromosomes? 6 46 22 23
23 A human somatic cell contains 46 chromosomes (23 pairs). A gamete contains half that number (one chromosome of each pair), or 23 chromosomes.
Which of the following describes the number of chromosomes in eukaryotic cells? It is the same in almost all species. It varies very little from species to species. It varies considerably between different species.
3
A characteristic ______ segregation in the F2 generation is referred to as the Mendelian ratio for a monohybrid cross. 3:1 2:2 4:1 1:1
3:1
What was the ratio that Mendel observed between dominant and recessive traits in the F2 offspring of a monohybrid cross? 1 dominant:3 recessive 3 dominant:1 recessive 4 dominant:1 recessive 1 dominant:1 recessive
3:1
After crossing over is complete, the homologous chromosomes remain attached at the chiasmata. How many chromatids are attached at this point? 2 3 4 1
4
After meiosis is complete which of the following are produced? Four daughter cells that are diploid Four daughter cells that are haploid Two daughter cells that are haploid Two daughter cells that are diploid
4 cells, haploid
Identify the diploid number of chromosomes in humans. 69 46 23 92
46
During anaphase ______, sister chromatids are pulled towards opposite poles as their kinetochore microtubules, which are attached to the poles, are shortened. A B
A
Gametes produced by meiosis contain which of the following? A Both paternal and maternal chromosomes which have been subject to crossing over B Exact copies of both paternal and maternal chromosomes C Only paternal chromosomes D Only maternal chromosomes
A
The reason for the monopolar arrangement of sister chromatids in meiosis I is that it allows for which of the following? A. Each joined pair of homologues to align on the metaphase plate B. Each individual homologue to align on the metaphase plate C. Crossing-over between non-sister chromatids
A
Select all that apply Damage to DNA can halt division of the cell at which cycle(s)? G2/M checkpoint G1/S checkpoint Spindle checkpoint
G2/M G1/S
At the end of anaphase I in meiosis, each pole of the cell contains which of the following? A. A haploid set of non-duplicated chromosomes B. A diploid set of duplicated chromosomes C. A set of homologous pairs D. A haploid set of duplicated chromosomes
D.
In meiosis, the random orientation of homologous chromosomes on the metaphase plate leads to A. synapsis of maternal and paternal chromosomes in the gametes B. segregation of maternal and paternal chromosomes in the gametes C. crossing over of maternal and paternal chromosomes in the gametes D. independent assortment of maternal and paternal chromosomes in the gametes
D.
When performing a monohybrid cross, Mendel noticed that not all individuals in the F2 generation were true breeding. What proportion were not? A. 2/3 of the F2 individuals exhibiting the dominant form were not true breeding. B. All of the F2 individuals exhibiting the recessive form were not true breeding. C. 1/3 of the F2 individuals exhibiting the recessive form were not true breeding. D. 1/2 of the F2 individuals exhibiting the dominant form were not true breeding.
D.
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)? A. alternative forms of genes are called alleles B. each individual receives one copy of each gene from each parent C. parents transmit genes to offspring D. the two alleles are usually the same E. the presence of an allele doesn't ensure that it will be expressed
D.
The role of the p53 protein is to detect damaged __. protein cell membranes DNA RNA
DNA
Two irreversible points in the cell cycle are replication of _______ material and ______________ of sister chromatids.
DNA Separation
Nucleosomes are composed __________ of and __________ proteins.
DNA histone
Some cells remain in the ________ phase permanently while others can proceed to the G1 phase when new cells are needed (e.g., during an injury).
G0
Some cells, such as muscle and nerve cells, remain permanently in which of the following phases of the cell cycle? S phase G0 phase G1 phase G2 phase
G0
The _____________ phase is considered a resting phase in the cell cycle.
G0
In a cell's life, cell growth occurs primarily during what phase? G0 M G1 S
G1
Which of the following checkpoints is the phase during which growth factors affect the cell cycle and the phase that links cell division to cell growth and nutrition? G2/M checkpoint G1/S checkpoint Cytokinesis Spindle checkpoint
G1/S
Condensation of chromosomes is initiated in the _______ phase of interphase and continues until the end of prophase.
G2
Replicated chromosomes begin to condense during which phase of the cell cycle? G0 G2 S G1
G2
Which of the following phases occurs after the replication of DNA and before the start of mitosis? G1 G2 S G0
G2