Module 2 Flashcards
How big are typical bacterial cells compared to eukaryotic cells?
Bacterial cells: ~1-10 micrometers.
Eukaryotic cells: ~10-100 micrometers.
Three ways bacterial DNA distinguishes from Eukaryotic DNA
- Circular
- not bound by histones
- found in the nucleoid region.
What makes homologous chromosomes homologous?
They have the same genes at the same loci but may carry different alleles
one of two identical copies of a single chromosome connected by a centromere.
Sister chromatid
Which allele is expressed in the phenotype of each of the following genotypes, assuming complete dominance?
Homozygous dominant (AA):
Heterozygous (Aa):
Homozygous recessive (aa):
Homozygous dominant (AA): Dominant allele is expressed.
Heterozygous (Aa): Dominant allele is expressed.
Homozygous recessive (aa): Recessive allele is expressed
A sister chromatid forms during which phase of the cell cycle when DNA is replicated?
S phase
In a diploid cell, how many copies of each type of autosome are there? What about in a triploid cell? Pentaploid?
Diploid (2N): Two copies of each autosome.
Triploid (3N): Three copies of each autosome.
Pentaploid (5N): Five copies of each autosome.
In humans, which chromosomes are the sex chromosomes and which are the autosomes?
Sex chromosomes: X and Y.
Autosomes: Chromosomes 1–22.
What is the term for bacterial cell division?
Binary fission
How long does bacterial cell division typically take?
duration varies depending on environmental conditions, but under optimal conditions, about 20 minutes
name major events in each stage of the Eukaryotic cell cycle
G1 phase: Cell growth.
S phase: DNA replication.
G2 phase: Preparation for mitosis.
M phase: Division into two daughter cells (prophase, metaphase, anaphase, telophase)
Diagram a diploid cell (2N=4) completing mitosis. On each chromosome place two genes, and assume each member of a homologous pair of chromosomes carries a different
allele of the two genes that reside on it. Use letters to denote genes, and upper/lowercase
to indicate alleles.
Diagram two homologous pairs, each with two genes, e.g., G/g and R/r. During mitosis, replicate each chromosome, align them at metaphase, and separate sister chromatids at anaphase.
- In regard to your diagram for #13 above:
A. How many daughter cells are produced by one round of mitosis?
B. What is their ploidy level compared to their parent cell?
C: Are the daughter cells genetically identical or variable compared to each other?
D. Are the daughter cells genetically identical or variable compared to their parent cell?
E. How much DNA is in the parent cell at METAPHASE relative to the resulting daughter cells when mitosis is complete?
A: Two daughter cells
B: ploidy level remains the same as the parent cell (e.g., diploid (2N) if the parent is diploid
C: The daughter cells are genetically identical to each other
D: The daughter cells are genetically identical to the parent cell
E: The parent cell has twice the DNA of each daughter cell at metaphase due to replication. After mitosis, each daughter cell has the same DNA amount as the original parent cell pre-replication.
Draw the following scenarios:
a. Diploid parent cell, 2N=6, late prophase of mitosis:
b. Haploid parent cell, 1N=5, anaphase of mitosis:
c. Triploid parent cell, 3N=6, metaphase of mitosis:
d. Tetraploid parent cell, 4N=12, telophase of mitosis:
a. Chromosomes condensed, nuclear envelope dissolving, spindle forming.
B. Sister chromatids separating.
C. Chromosomes aligned at metaphase plate.
D. Chromosomes decondensing, nuclear envelopes reforming.
- In regard to your diagram for #17 above:
A. How many daughter cells are produced by one complete round of meiosis?
B. What is their ploidy level compared to their parent cell?
C. Are the daughter cells genetically identical or variable compared to each other?
D. Are the daughter cells genetically identical or variable compared to their parent cell?
E. How much DNA exists in the parent cell at metaphase I relative to the daughter cells after meiosis I is complete?
F. How much DNA exists in the parent cell at metaphase I relative to the daughter cells after meiosis II is complete?
A: Four daughter cells
B: The daughter cells are haploid (N), which is half the ploidy of the diploid (2N) parent cell
C: The daughter cells are genetically variable due to crossing over and independent assortment
D: The daughter cells are genetically variable compared to the parent cell
E: e. The parent cell at metaphase I has twice the DNA of each daughter cell after meiosis I.
F: The parent cell at metaphase I has four times the DNA of each daughter cell after meiosis II.
Draw the following scenarios:
a. Diploid parent cell, 2N=6, late prophase of meiosis I:
b. Diploid parent cell, 2N=6, anaphase of meiosis I:
c. Diploid parent cell, 2N=4, telophase of meiosis II:
d. Tetraploid parent cell, 4N=8, metaphase of meiosis I:
e. Tetraploid parent cell, 4N=8, metaphase of meiosis II:
a. Homologous chromosomes paired, crossing over occurring.
b. Homologous chromosomes separating.
c. Chromosomes decondensing, nuclear envelopes reforming.
d. Homologous chromosomes aligned at metaphase plate.
E. Sister chromatids aligned at metaphase plate.
- Compose a limerick highlighting at least one key difference between mitosis and meiosis (AABBA):
In mitosis, cells grow and repair,
While meiosis ensures genes can pair.
One makes cells that are twins,
The other reshuffles within,
Creating gametes with traits to compare.
Is it possible for a haploid cell to fully complete meiosis? Why or why not?
No, a haploid cell cannot complete meiosis because it lacks homologous chromosome pairs needed for the process.
F. FtsZ
A. Karyotype
H. Gamete
C. Diploid
J. Sex Chromosome
B. Locus
D. Haploid
G. Somatic Cell
E. Fission
I. Autosome
- The complete set of chromosomes in a cell, organized by size and type.
- The specific location of a gene on a chromosome.
3.A cell with two sets of chromosomes (2N). - A cell with one set of chromosomes (N).
- A type of asexual reproduction where a cell divides into two identical cells.
- A protein that helps bacteria divide by forming a ring at the cell’s midpoint.
- Any cell in the body except reproductive cells.
- A reproductive cell (e.g., sperm or egg) that is haploid.
- Non-sex chromosomes that determine traits other than sex.
- Chromosomes that determine the sex of an individual (X and Y in humans).
A. Karyotype
B. Locus
C. Diploid
D. Haploid
E. Fission
F. FtsZ
G. Somatic Cell
H. Gamete
I. Autosome
J. Sex Chromosome
- A reproductive cell (e.g., sperm or egg) that is haploid.
- Non-sex chromosomes that determine traits other than sex.
- Chromosomes that determine the sex of an individual (X and Y in humans).
- The region where sister chromatids are connected.
- The protein structure on chromosomes where spindle
- fibers attach.
- The pairing of homologous chromosomes during meiosis I.
- Exchange of genetic material between homologous chromosomes during meiosis I.
- Asexual reproduction in bacteria.
- Cell division resulting in two identical daughter cells.
- Cell division that produces four genetically distinct haploid cells.
- Enzyme that breaks down cohesin to allow chromatids to separate.
- Protein that holds sister chromatids together until separation.
H. Gamete
I. Autosome
J. Sex Chromosome
K. Centromere
L. Kinetochore
M. Synapsis
N. Crossing Over/Recombination
O. Binary Fission
P. Mitosis
Q. Meiosis
R. Separase
S. Cohesin
