Exam 1 Chapter 3
tetrad
A bivalent is also called a .............., because it is composed of four chromatids.
two pairs of sister chromatids
A bivalent, or tetrad, consists of ______. Multiple choice question. two chromatids of a replicated chromosome two pairs of sister chromatids two non-homologous chromosomes a sister chromatid and a non-sister chromatid
Blank 1: homologous or homolog Blank 2: meiosis
A fundamental principle of the chromosome theory of inheritance involves the chromosome composition of cells. Most eukaryotic cells are diploid, containing chromosomes that are found in ................. pairs. During the process of .......................... , the two members of each pair segregate into different daughter nuclei.
homolog meiosis
A fundamental principle of the chromosome theory of inheritance involves the chromosome composition of cells. Most eukaryotic cells are diploid, containing chromosomes that are found in ....................... pairs. During the process of ................. , the two members of each pair segregate into different daughter nuclei.
autosomes
A human cell contains two main types of chromosomes: sex chromosomes and ......................
A = synaptonemal complex ; B = chiasma
A pair of homologous chromosomes is shown here. Which of the following combinations show correct matches? Multiple choice question. A = chiasma ; B = synaptonemal complex A = synaptonemal complex ; B = chiasma A = cleavage furrow ; B = synaptonemal complex A = cleavage furrow ; B = chiasma A = synaptonemal complex ; B = cleavage furrow
40 chromosomes, each consisting of two chromatids
After a mitotic division is complete, a daughter cell has 40 chromosomes. Which of the following best describes the chromosome composition of the mother cell in the G2 phase? Multiple choice question. 40 chromosomes, each consisting of two chromatids 80 chromosomes, each consisting of two chromatids 40 chromosomes, each consisting of one chromatid 80 chromosomes, each consisting of one chromatid
chromatids
After replication, each chromosome consists of two copies called ................
chromosome replication occurs during the S phase of the cell cycle
All of the following are fundamental principles of the chromosome theory of inheritance except ______.
the connections that result from crossing-over
Chiasmata refers to ______. Multiple choice question. the cleavage furrow that forms during cytokinesis protein complexes that help in chromosome replication the connections that result from crossing-over a stage in prophase I of meiosis
the structures within living cells that contain the genetic material
Chromosomes are best defined as ______. Multiple choice question. the units of inheritance that code for proteins the structures within living cells that hold the nucleus in place the structures within living cells that contain the genetic material the units of inheritance that are composed of RNA
autosomes
Chromosomes that are not sex chromosomes are called ______. Multiple choice question. autosomes euchromatin protosomes heterochromatin
sex chromosome
Chromosomes that determine whether an individual is a male or female are called ........................
Anaphase I of meiosis
Consider a diploid cell with 2n = 6. This cell is shown in which phase of cell division? Multiple choice question. Metaphase of mitosis Anaphase I of meiosis Metaphase II of meiosis Anaphase II of meiosis Anaphase of mitosis
four; eight
Consider an organism that has four pairs of chromosomes. At the end of meiosis I, each cell would have ______ chromosomes and ______ chromatids. Multiple choice question. four; eight two; four eight; eight four; four
three; six
Consider an organism that has three pairs of chromosomes. At the start of meiosis II, each cell would have ______ chromosomes and ______ chromatids. Multiple choice question. six; six six; three three; three three; six
prometaphase I
During ______ ______ of meiosis, the spindle apparatus is complete and the chromatids are attached via kinetochore microtubules. Multiple choice question. telophase I prometaphase I anaphase II prophase II
telophase I
During ______ of meiosis, the pairs of sister chromatids (or dyads) reach the opposite poles of the cell, where in most cases, they decondense. Multiple choice question. anaphase I metaphase I metaphase II telophase I prophase II
kinetochore microtubule
During metaphase I of meiosis, one pair of chromatids in a bivalent (but not both) is attached to a ______. Therefore, each pair of sister chromatids is attached to only one pole. Multiple choice question. centrosome polar microtubule nucleolus metaphase plate telomere kinetochore microtubule
synapsis
During prophase of meiosis I, homologous chromosomes recognize and begin to align with each other via a process called .............
centrosomes spindle
During prophase of mitosis, the nuclear membrane breaks down into small vesicles and the nucleolus becomes less visible. Furthermore, the two ................ move apart from each other and the mitotic .................. begins to form.
Metaphase of meiosis I
During which of the following phases are tetrads organized along a plate in the center of the cell? Multiple choice question. Prophase of meiosis II Metaphase of mitosis Prophase of meiosis I Metaphase of meiosis II Metaphase of meiosis I
centrioles,
Each centrosome of an animal cell contains a pair of ................... at right angles to each other.
cell cycle
Eukaryotic cells that are destined to divide progress through G1, S, G2, and M phases, which are collectively known as the ......................
meiosis
Eukaryotic cells that are diploid can divide by ______ to produce haploid sex cells. Multiple choice question. binary fission meiosis mitosis multiple fission
linked
Genes that are physically located on the X chromosome are called X- .............. genes.
metaphase I
In ______ of meiosis, the bivalents (which are also termed tetrads) are aligned along the center of the cell. Multiple choice question. prophase II metaphase II anaphase II prophase I anaphase I metaphase I
testcross
In a Drosophila melanogaster ................., a fly with a dominant phenotype and unknown genotype is mated to one that has a recessive phenotype.
interphase
In actively dividing cells, the G1, S, and G2 phases are collectively known as .................
meiosis
In eukaryotes, ______ is the type of cell division that is responsible for the production of gametes. Multiple choice question. mitosis meiosis binary fission
Blank 1: embryo Blank 2: sac
In flowering plants, the female gametophyte is a seven-celled structure called the....................
pollen grain
In flowering plants, the male gametophyte with a thick cell wall is called the ......................
is the same for all individuals of the species
In general, the chromosome number of a particular species ______. Multiple choice question. is the same for all individuals of the species varies depending on the environmental conditions varies depending on the age of the individual is different for males and females of the species
heterogametic, homogametic
In humans, the male is known as the ............... sex, because one type of sperm carries only the X chromosome, and another type carries the Y chromosome. The female, on the other hand, is the ................... sex because all eggs carry a single X chromosome. Listen to the complete question
non-sister; homologous
In meiosis, crossing over refers to the physical exchange of pieces between ______ chromatids of ______ chromosomes. Multiple choice question. sister; non-homologous non-sister; non-homologous sister; homologous non-sister; homologous
X0 XX
In the X-0 system of sex determination, the male's chromosomes are listed as .................. , whereas the female's chromosomes are listed as ................
Blank 1: synaptonemal Blank 2: complex Blank 3: chiasma, bivalent,
In this figure label A points to the ..............., while label B shows the , ................... which is the connection that results from a crossing over.
spermatogenesis
Male animals produce mature sperm by a process called
anthers ovary
Meiosis in flowering plants occurs in two different parts of the sporophyte: the ..................., which produce the male gametophyte, and the ................., which produce the female gametophyte.
segregation
Mendel's law of .............. can be explained by the homologous pairing and separation of chromosomes during meiosis.
binary fission
Most bacterial cells divide by ______. Multiple choice question. mitosis budding binary fission fragmentation
nucleoid
Prokaryotes usually have a single type of circular chromosome in a region of the cytoplasm called the ______. nucleoplasm nucleus nucleolus nucleoid
Blank 1: bacteria Blank 2: archaea
Prokaryotes, which include the .............. and the ..................., are organisms that lack a membrane-bound nucleus. Listen to the complete question
The chromatids become condensed. The mitotic spindle begins to form. The nucleolus becomes less visible. The nuclear membrane begins to dissociate into small vesicles
Select all of the following events that occur during prophase. Multiple select question. The two centrosomes are replicated. The chromatids become condensed. The mitotic spindle begins to form. The nucleolus becomes less visible. The nuclear membrane begins to dissociate into small vesicles
Homologues have reached their respective poles The nuclear membrane reforms in most species
Select all of these that are events of telophase I of meiosis. Multiple select question. The nuclear membrane breaks down in most species Homologues have reached their respective poles The nuclear membrane reforms in most species Chromosomes condense in most species Homologues are aligned at the center of the cell
gametes ; fertilization
Sexual reproduction involves the fusion of two ______ in the process of ______. Multiple choice question. gametes ; gametogenesis somatic cells ; gametogenesis somatic cells ; fertilization gametes ; fertilization
testes
Spermatogenesis takes place in the ______. Multiple choice question. seminal vesicles prostate gland testes penis
homologous chromosomes recognize each other and begin to align themselves in prophase I.
Synapsis is the process by which ______.
anaphase
The .................. stage of meiosis I is characterized by the separation of the two pairs of sister chromatids within a bivalent from each other and their migration to opposite poles of the cell.
nucleoid
The ................... of a prokaryotic cell is the region of cytoplasm that contains the chromosome.
Sry
The ..................... gene on the Y chromosome plays a key role in causing the development of male characteristics.
mammals
The X-Y system of sex determination is used by ______. Multiple choice question. birds mammals reptiles plants insects
The homologs segregate during meiosis I and the sister chromatids separate during meiosis II
The behavior of chromosomes during meiosis explains Mendel's law of segregation. Specifically, a gamete contains only one copy of each type of chromosome because of which of the following? Multiple choice question. The homologs segregate during meiosis I and then again during meiosis II The homologs segregate during meiosis I and the sister chromatids separate during meiosis II The sister chromatids segregate during meiosis I and then again during meiosis II The sister chromatids segregate during meiosis I and the homologs separate during meiosis II
region of the chromosome where the sister chromatids join
The centromere is a ______. Multiple choice question. complex of proteins that helps in replicating DNA complex of proteins that forms at the site of cell division region of DNA that serves as an origin of replication region of the chromosome where the sister chromatids join
Blank 1: Boveri Blank 2: Sutton
The chromosome theory of inheritance was a milestone in our understanding of genetics. It was independently proposed by Theodore ......................, a German biologist, and American geneticist Walter .......................
female gametophyte
The embryo sac is the _______ in flowering plants. Multiple choice question. female sporophyte male gametophyte male sporophyte female gametophyte
four; G1, G2, S, and M
The eukaryotic cell cycle is composed of ______ phases called ______. Multiple choice question. four; G1, G2, S, and M three; G1, G2, and M four; G0, G1, G2, and S three; G1, G2, and S
crossing over
The interchange of corresponding chromatid segments of homologous chromosomes during prophase I of meiosis is called ______ ______. crossing over assortment mutation segregation
gametophyte sporophyte
The life cycles of plant species alternate between haploid and diploid generations. The haploid generation is called the ................... , whereas the diploid generation is called the...............
G2 G1
The meaning of the term chromosome can differ depending on the stage of the cell cycle we are observing. During ................... phase of interphase and early stages of M phase, a chromosome refers to a pair of sister chromatids (a dyad). However, at the end of M phase and during .................................................phase of interphase, a chromosome refers to a monad which contains the equivalent of one chromatid.
male gametophyte
The pollen grain is the ______ in flowering plants. Multiple choice question. male gametophyte female gametophyte female sporophyte male sporophyte
distribute the replicated chromosomes equally into the two daughter cells
The primary purpose of mitosis is to ______. Multiple choice question. ensure proper replication of the genetic material during the S phase of the cell cycle distribute the replicated chromosomes equally into the two daughter cells enhance the genetic diversity of a species via crossing-over between chromosomes
independent assortment
The random arrangement of homologs along the metaphase plate in meiosis I is consistent with Mendel's law of.............................
chiasma
The structure that is formed during crossing over is called a(n) .............., because it looks like the Greek letter chi, χ.
chromosomes
The structures within all living cells that contain the genetic material are called .
chromosome
The term that can refer to either a dyad (pair of sister chromatids) or a monad (single chromatid) is a(n) ....................
centromere
The two chromatids of a chromosome are joined together at a region of DNA called the ......................
sister chromatids
The two copies of a replicated chromosome are called ______. Multiple choice question. homologous chromosomes centrosomes alleles sister chromatids
centrosomes
The two microtubule-organizing centers (MTOCs) that form the mitotic spindle of animal cells are called ______. Multiple choice question. centrosomes centrophores centromeres centrioles
Anaphase II of meiosis
This diagram represents a cell that has an original diploid number (2n) of six chromosomes. The cell is shown in which phase of cell division?
binary fission
This figure shows a bacterium reproducing asexually by a process known as .......................
True
True or false: A heterogametic sex produces two types of sex cells, while a homogametic sex produces sex cells of only one type. True false question.TrueFalse
True
True or false: Each species has a particular chromosome composition. True false question. True False
False
True or false: Most eukaryotic species are haploid or have such a phase as a significant part of their life cycle. True False
False
True or false: Sex chromosomes are chromosomes that determine sex in all species. True false question. True False
asexual
Unicellular prokaryotic organisms proliferate by .................. reproduction, in which a preexisting cell divides to produce two new cells.
Independent alignment of different homologous pairs along the metaphase I plate
What aspect of chromosome behavior is consistent with Mendel's law of independent assortment? Multiple choice question. Movement of sister chromatids to opposite poles during anaphase II of meiosis Replication of chromosomes during the S phase prior to meiosis Independent alignment of different homologous pairs along the metaphase I plate Production of genetically identical daughter cells during mitosis
A complex between DNA and proteins that is found in eukaryotic cells
What is chromatin? Multiple choice question. Another term for the DNA molecule found in a prokaryotic cell Another term for the DNA molecules found in a eukaryotic cell A complex between DNA and proteins that is found in prokaryotic cells A complex between DNA and proteins that is found in eukaryotic cells
chromatin
What is the name for the diffuse complex of DNA and proteins in a eukaryotic cell? Multiple choice question. chromatin nucleoplasm nucleoid chromophore
Sexual reproduction
What process involves the fusion of gametes in fertilization to produce a new organism? Multiple choice question. Mitosis Sexual reproduction Asexual reproduction Binary fission Meiosis
S G2 G1
Which of the following are part of interphase? Multiple select question. S G2 M Cytokinesis G1
A mother cell divides to produce two identical daughter cells
Which of the following best describes asexual reproduction? Multiple choice question. A mother cell divides to produce four unique daughter cells Two haploid gametes fuse to form a diploid cell A mother cell divides to produce two identical daughter cells
One pair of sister chromatids is linked to one pole, and the homologous pair is linked to the other
Which of the following best describes how chromosomes are attached to microtubules during metaphase I of meiosis? Multiple choice question. A pair of sister chromatids is linked to both poles Each member of a homologous pair of chromosomes is linked to both poles One pair of sister chromatids is linked to one pole, and the homologous pair is linked to the other
The two pairs of sister chromatids separate and move to opposite poles.
Which of the following best describes the events of anaphase I of meiosis? Multiple choice question. The two pairs of sister chromatids separate and move to opposite poles. The sister chromatids of each chromosome migrate to opposite poles. The two pairs of sister chromatids migrate to the same pole.
2n → 1n
Which of the following best describes the outcome of meiosis I in humans? Multiple choice question. 1n → 1n 1n → 2n 2n → 2n 2n → 1n
23 dyads
Which of the following best describes the starting material found in each cell entering meiosis II in humans? Multiple choice question. 46 dyads 23 bivalents 23 monads 46 monads 23 dyads
Sry
Which of the following genes plays a key role in male development? Multiple choice question. Yac Sry Xist Xec
A cross between a white-eyed male and a red-eyed female
Which of the following is an example of a testcross in Drosophila melanogaster? Multiple choice question. A cross between a white-eyed male and a red-eyed female A cross between a red-eyed male and a white-eyed female A cross between a white-eyed male and a white-eyed female
Most eukaryotic species are diploid or have a diploid phase to their life cycle.
Which of the following statements about eukaryotes is true? Multiple choice question. All eukaryotic species are diploid or have a diploid phase to their life cycle. Few eukaryotic species are diploid or have a diploid phase to their life cycle. Most eukaryotic species are diploid or have a diploid phase to their life cycle.
Both synapsis and crossing over occur in prophase I of meiosis
Which of the following statements about synapsis and crossing over is true? Multiple choice question. Both synapsis and crossing over occur in prophase I of meiosis Synapsis occurs in prophase I and crossing over occurs in prometaphase I of meiosis Both synapsis and crossing over occur in prometaphase I of meiosis Synapsis occurs in prometaphase I and crossing over occurs in prophase I of meiosis
The male has one sex chromosome (the X) and is designated X0, whereas the female has two X chromosomes.
Which of the following statements about the X-0 system of sex determination is true?
The male is XY and the female is XX.
Which of the following statements about the X-Y system of sex determination is true? Multiple choice question. The female is XX and the male is YY. The male is XY and the female is XX. The female is XY and the male is XX. The male is XY and the female is YY.
The anthers of the sporophyte produce the male gametophyte, while the ovaries of the sporophyte produce the female gametophyte.
Which of the following statements about the life cycle of flowering plants is true?
Certain cells in the sporophyte undergo meiosis to produce haploid cells, which divide by mitosis to produce a gametophyte.
Which of the following statements about the life cycle of plants is true?
prokaryotes
Which term best describes organisms whose chromosomes are not contained within a membrane-bound nucleus? Multiple choice question. progenotes prokaryotes archaeotes eukaryotes
Theodore Boveri Walter Sutton
Which two scientists independently proposed the chromosome theory of inheritance? Multiple select question. Walther Fleming Theodore Boveri Carl Nageli Walter Sutton August Weismann
X-linked
_______ genes are those that are physically located on the X chromosome. Multiple choice question. X-linked X-associated X-influenced X-limited