Patterns of Chromosomal Inheritance - Chapter 19 Flashcards
DNA is found in association with proteins within the cell. What is the term for this DNA-protein complex?
Centromere
nucleus
Karyotype
Chromatids
Chromatin
Chromatin
*Collectively, the DNA and associated proteins are referred to as chromatin. The nucleus is the structure that contains the genetic material. A karyotype is a display of chromosomes. The centromere is a condensed region of chromosomes to which microtubules attach during mitosis, and that holds the chromatids together.
In humans, how many of the chromosomes are autosomes?
22
46
23 pairs
22 pairs
1 pair
22 pairs
*Pairs 1-22 are considered autosomes. The 23rd pair is made up of sex chromosomes.
In a karyotype, it can be seen that a homologous pair of duplicated chromosomes will contain how many chromatids?
One
Two
Three
Four
Six
Four
*A duplicated chromosome contains two identical sister chromatids. Thus a pair of homologous duplicated homologous chromosomes contains four chromatids.
Interphase can be divided into how many distinct phases?
Three
DNA
Interphase
Anaphase
Metaphase
Hours
Three
During the S, or synthesis, phase of interphase the [____________] is replicated.
Three
DNA
Interphase
Anaphase
Metaphase
Hours
DNA
Most eukaryotic cells spend most of their time in [_____________] and very little time in the dividing process of mitosis.
Three
DNA
Interphase
Anaphase
Metaphase
Hours
Interphase
Mitosis consists of prophase, metaphase, [_____________] and telophase.
Three
DNA
Interphase
Anaphase
Metaphase
Hours
Anaphase
During [______________] of mitosis, the chromosomes line up in the middle, or equator, of the cell.
Three
DNA
Interphase
Anaphase
Metaphase
Hours
Metaphase
From interphase to cytokinesis, the entire process of cell division can take an average of 10-20 [____________] in a typical plant or animal cell.
Three
DNA
Interphase
Anaphase
Metaphase
Hours
Hours
How are G1 and G2 different?
In G1, the cell prepares to synthesize its DNA and in G2, it synthesizes the proteins needed for cell division.
The cell copies its DNA during G1 but not G2.
Mitosis occurs during G1 but not during G2.
The cell spends much more time in G2 than in G1.
The cell does not grow during G1 but doubles its organelles in G2.
In G1, the cell prepares to synthesize its DNA, while in G2, it synthesizes the proteins needed for cell division.
*In G1, the cell prepares to synthesize its DNA, while in G2, the cell synthesizes the proteins needed for cell division.
How are mitosis and cytokinesis alike?
Both involve mitochondria.
Both involve division.
Both involve DNA synthesis.
Both involve apoptosis.
Both involve division.
*Both mitosis and cytokenisis involve division. In mitosis the chromosomes divide, while in cytokinesis the cytoplasm divides.
External signals, such as hormones and growth factors, can stimulate a cell to go through the cell cycle.
True
False
True
*The cell cycle can be controllled externally by hormones and growth factors.
Which of the following is a stage of interphase?
S
G1
G2
All of the answer choices are stages of interphase.
All of the answer choices are stages of interphase.
*All of the answer choices are stages of interphase.
What happens at the G2 checkpoint?
The cell receives external signals to divide.
The cell makes a commitment to divide.
The cell enters G0.
The cell makes sure the chromosomes are lined up correctly.
The cell checks that the DNA has replicated.
The cell checks that the DNA has replicated.
*At the G2 checkpoint, the cell verifies that the DNA has replicated.
How do proto-oncogenes affect the cell cycle?
They cause it to temporarily pause and the rapidly accelerate.
They do not affect the cell cycle.
They rapidly accelerate it and then cause it to pause.
They stimulate it.
They inhibit it.
They stimulate it.
*Proto-oncogenes stimulate the cell cycle.
What is the structure that holds the chromatids together?
Centromere
Chromatin
Karyotype
Chromosomes
None of the answer choices is the structure that holds the chromosomes together.
Centromere
*The centromere holds the chromatids together. Chromatin is collectively the DNA and proteins. The chromosomes are responsible for the transmission of genetic material from one generation to the next. A karyotype is a picture of the chromosomes.
If a cell has four pairs of chromosomes, after mitosis each daughter cell will have how many chromosomes?
32
16
8
4
2
8
*Each will have four pairs, or eight chromosomes.
Which of the following is part of the mitotic spindle?
Nucleolus
Sister chromatid
Centromere
Aster
Nuclear membrane
Aster
*The aster is an array of microtubules at the poles that make up part of the mitotic spindle.
At which stage of mitosis do you first see the chromosomes appearing?
Telophase
Cytokinesis
Metaphase
Prophase
Anaphase
Prophase
*The chromosomes first become visible under a light microscope during prophase.
Which of the following is not a stage of mitosis?
Prophase
Anaphase
Interphase
Metaphase
Telophase
Interphase
*Interphase is not part of mitosis.
At what stage of mitosis do sister chromatids become full-fledged chromosomes?
Metaphase
Anaphase
Cytokinesis
Prophase
Telophase
Anaphase
*The sister chromatids split during anaphase and become chromosomes.
At which stage of mitosis do the chromosomes look like the letter “V”?
Prophase
Telophase
Cytokinesis
Anaphase
Metaphase
Anaphase
*During anaphase, the chromosomes are being pulled apart by the spindle apparatus attached at the centromere. The centromere moves toward the poles trailing the arms of the chromosome behind, looking like a “V”.
What structure is not divided during cytokinesis?
Cell membrane
Endoplasmic reticulum
Cytoplasm
Cell wall
Chromosome
Chromosome
*Chromosomes are divided during mitosis as part of the nuclear division. The cell membrane, cell wall, cytoplasm, and endoplasmic reticulum are part of the division of the cytoplasm (cytokinesis).
In meiosis how many divisions occur and how many daughter cells are created?
Two, four
One, four
One, two
Two, two
Two, eight
Two, four
*In meiosis, there are two division resulting in four daughter cells.
In what stage of meiosis does synapsis occur?
Metaphase I
Prophase I
Metaphase II
Prophase II
Anaphase I
Prophase I
*Synapses are related to crossing over and occur when the chromosomes first appear in prophase I.
During which phase of meiosis will the homologous chromosomes pair up?
Metaphase I
Telophase II
Prophase I
Anaphase I
Prophase II
Prophase I
*Homologous chromosomes pair up during prophase I of meiosis. There is no pairing of chromosomes during prophase II. Homologous chromosomes separate during anaphase I. Four haploid daughter cells form as a result of telophase II. Homologous duplicated chromosomes are lined up at the equator during metaphase I.
Independent alignment creates genetic variation. This is associated with which state of meiosis?
Anaphase II
Prophase II
Metaphase I
Prophase I
Metaphase II
Metaphase I
*Independent alignment occurs when the homologues line up at the metaphase plate during meiosis I.
In what way is spermatogenesis similar to oogenesis?
Both result in cells with half the diploid chromosome number.
Both are arrested in prophase I.
Both result in four daughter cells.
Both occur continuously from puberty on.
Both result in one or two polar bodies.
Both result in cells with half the diploid chromosome number.
*Both are forms of meiosis which the daughter cells contain half the diploid chromosome number. Oogenesis will pause during the course of the monthly cycle. Only spermatogenesis will result in four daughter cells. Oogenesis produces one egg and two to three polar bodies. Spermatogenesis does not pause in prophase I. Only oogenesis results in polar bodies.
The products of meiosis I in spermatogenesis are
Two identical cells.
Secondary spermatocytes.
Spermatids.
Primary spermatocytes.
Spermatozoa.
Secondary spermatozoa.
*The primary spermatocytes undergoes meiosis I to produce two secondary spermatocytes. Spermatids are the result of meiosis II. Spermatids mature into sperm (spermatozoa). Polar bodies are a product of oogenesis.
If the secondary oocyte is not fertilized, it does not complete meiosis II.
True
False
True
*Fertilization is required for the completion of meiosis II in oogenesis.
All the products of oogenesis are equal in size and content.
True
False
False
*The polar body(ies) are much smaller as the egg receives all of the cytoplasm.
How many cells are produced as the result of meiosis and mitosis?
Four, two
Four, four
Two, four
Two, two
It varies each time the cells go through meiosis and mitosis.
Four, two
*Meiosis will produce four cells as a result of the cycle. Mitosis will produce two cells as a result of the cycle.
In which stage of meiosis do homologous chromosomes separate from each other?
Anaphase II
Interkinesis
Metaphase II
Anaphase I
Metaphase I
Anaphase I
*Homologous chromosomes separate during anaphase I.
When does the centromere divide in meiosis?
Anaphase II
Anaphase I
Prophase II
Telophase I
Prophase I
Anaphase II
*The centromeres divide in anaphase II when the sister chromatids separate.
Which division of meiosis is like mitosis?
G1
S
Meiosis I
G2
Meiosis II
Meiosis II
Meiosis II is similar to mitosis is that sister chromatids separate during anaphase. G1, S, and G2 are parts of interphase.
Which phase of meiosis matches those of mitosis in regards to the events occurring in the cell?
Anaphase II and anaphase
Metaphase I and prophase
Anaphase I and prophase
Telophase II and telophase
None of the phases of meiosis will match up with mitosis.
Anaphase II and anaphase
*During anaphase II and anaphase, the sister chromatids will separate and become daughter chromosomes that move to the poles.
How many chromosome pairs does a human have?
92
46
50
23
26
23
*Humans have 23 pairs of chromosomes.
If nondisjunction occurs during meiosis I, how many of the final four products will be abnormal?
Zero
Four
One
Two
Three
Four
*All four daughter cells will be abnormal.
If nondisjunction occurs during meiosis II (to one of the cells resulting from meiosis I), how many of the final four products will be abnormal?
Zero
One
Two
Three
Four
Two
*If nondisjunction occurs in meiosis II, then two of the resulting cells will have abnormal chromosome numbers.
Suppose that nondisjuction occurs during meiosis II in oogenesis, and each of the resulting four cells is fertilized with a normal sperm (imagine four functional egg cells result from oogenesis). How many cells are normal and how many have a chromosomal trisomy?
Two, one
Three, one
One, three
One, two
Two, two
Two, one
*Two cells will be normal, one cell will have an extra copy (trisomy), and one cell will have a missing copy (monosomy).
Which of the following syndromes has a karyotype with a missing X chromosome?
Turner syndrome
Klinefelter syndrome
Williams syndrome
Jacobs syndrome
Down syndrome
Turner syndrome
*In Turner syndrome, the individual has only one sex chromosome, an X. The other X chromosome is missing.
What is the genetic makeup of an individual who has inherited Jacobs syndrome?
XO
XYY
XXY
XXX
None of the answer choices match an individual who has inherited Jacobs syndrome.
XYY
*An individual with Jacobs syndrome will have a genetic makeup of XYY. Poly-X females have more than two X chromosomes and extra Barr bodies in the nucleus. Klinefelter syndrome is characterized by a genetic makup of XXY. Turner syndrome is characterized by a female with one X chromosome.
Which of the following is a symptom of Down syndrome?
Short stature
Flat Face
Stubby fingers
Eyelid fold
All of the answer choices are symptoms of Down syndrome.
All of the answer choices are symptoms of Down syndrome.
*Down syndrome individuals include all of the answer choices.
How are Jacobs and Klinefelter syndromes alike?
Both have three sex chromosomes.
Both have only 45 chromosomes.
Both have one sex chromosome.
Both have only two X chromosomes.
Both have only two Y chromosomes.
Both have three sex chromosomes.
*In Klinefelter syndrome, the sex chromosomes are XXY; in Jacobs syndrome, the sex chromosomes are XYY. In both cases, there are three sex chromosomes.
In a translocation, all of the DNA is present, and there is only one copy of each piece.
True
False
True
*In a translocation, a portion of a chromosome is moved, but there are no deletions or duplications.
Which chromosomal mutation will cause Williams syndrome?
Translocation
Trisomy
Duplication
Inversion
Deletion
Deletion
*A deletion of the tip of chromosome 7 leads to Williams syndrome.
Which type of change in chromosome structure characterizes cri du chat syndrome?
Translocation
Duplication
Inversion
Deletion
Trisomy
Deletion
*In cri du chat syndrome, chromosome 5 is missing the end piece due to deletion.
When does a chromosome go from one chromatid to two sister chromatids?
During the G2 phase of interphase
During the S phase of interphase
During the G1 phase of interphase
During cytokinesis
During mitosis
During the S phase of interphase
*The DNA is duplicated during the S phase of interphase.
Cytokinesis is the division of the ____________.
Nucleus
Zygote
Chromosome
Cytoplasm
Chromatin
Cytoplasm
*Cytokinesis is the division of the cytoplasm. Mitosis is the division of the nucleus and chromosomes. The chromatin is divided during mitosis. Cleavage is the division of the zygote.
If you are looking at a cell in which 2n-16, and there appear to be 8 structures lined up at the metaphase plate, then you are looking at_______________.
G1
G2
Meiosis.
Interphase.
Mitosis.
Meiosis
*If there are only 8 structures, then the chromosomes are lined up as homologous pairs. Only in meiosis do homologous chromosomes line up at the metaphase plate. During mitosis, there would be 16 structures at the metaphase plate. During interphase, G1, and G2 the DNA is in the chromatin state.
Following mitosis, the daughter cells are identical to the parent cell.
True
False
False
*During mitosis, a diploid mother cell divides to produce two identical daughter cells.
Sexual reproduction introduces more genetic variation than does asexual reproduction
True
False
True
*Sexual reproduction creates genetically distinct daughter cells. Asexual (mitotic) reproduction creates daughter cells that are identical to the dividing cell and to one another.
Which stage comes directly after interphase?
S
G1
Cytokinesis
Mitosis
G2
Mitosis
*Mitosis, the division of the nucleus and chromosomes, is directly after interphase. It precedes cytokinesis, the division of cytoplasm. G1, S, and G2 are components of interphase.
If there are four pairs of chromosomes, how many different combinations of chromosomes are possible?
32
16
8
4
2
16
*There would be 24, or 16 possible combinations.
Trisomy of which pair of chromosomes has the greatest chance of survival?
XX
Pair 13
Pair 3
Pair 15
Pair 8
XX
*Trisomy of the X sex chromosomes (XXX) has the greatest chance of survival among those chromosomal pairs listed.
What structures are divided during cytokinesis?
Cell membrane and chromatin
Cytoplasm and chromosomes
None of the answer choices divide during cytokinesis.
Cytoplasm and organelles
Nuclei
Cytoplasm and organelles.
*During cytokinesis the cytoplasm and organelles are divided. The chromosomes/chromatin are divided during mitosis.
In both spermatogenesis and oogenesis, one sperm/egg forms from one primary spermatocyte/oocyte.
True
False
False
*In spermatogenesis, four sperms form from one primary spermatocyte; whereas in oogenesis, one egg forms from one oocyte.
When a child is born, mitosis ceases to function.
True
False
False
*The functions of mitosis are: growth, repair of damage, and replacement of old cells. This continues throughout life.
