Ch 9 Flashcards
What is the most predominant form of cellular replication?
The most predominant form of cellular replication creates genetically identical daughter cells
What are gametes?
Cells involved in sexual reproduction that are haploid (contain one copy of each chromosome).
What are somatic cells?
Most cells in the body that are diploid (contain two copies of each chromosome, called homologous chromosomes).
What is mitosis?
A type of cell division that results in two genetically identical daughter cells and occurs in somatic cells.
What is meiosis?
A type of cell division that results in four genetically unique haploid gametes and occurs in germ cells in the gonads.
What are the roles of mitosis?
- Reproduction
- Development
- Growth
- Tissue renewal
What is a genome?
The entirety of the genetic material in a cell.
Describe the structure of a chromosome
chromosome consists of a single double-stranded DNA molecule.
Describe the genome of prokaryotes.
Prokaryotes generally contain a single circular chromosome. They may also have extrachromosomal plasmids that carry beneficial (but nonessential) genes.
Describe the genome of eukaryotes.
- multiple linear xsomes in nucleus
Genetic info is also found in mitochondria and chloroplast
What is chromatin? What is it composed of
When replication is not occurring, DNA is found in the form of chromatin. Chromatin is composed of DNA and histone proteins.
What happens to DNA during cell division?
is condensed into chromosomes.
What is the structure of a duplicated chromosome?
consists of two sister chromatids (two copies of the same DNA) joined at the centromere.
The part of the chromatid on either side of the centromere is called an arm.
What is interphase
cell is not replicating
. During interphase, cells grow and are metabolically active, fulfilling their role(s) in the organism.
What happens during the G1 phase of interphase?
- cells grow and produce cellular components.
Some cells are non-dividing and shift permanently into the G0 phase (e.g., mature nerve and muscle cells).
Some cells temporarily move into the G0 phase to perform their cellular duties before being called back into the S phase
What happens during the S phase of interphase?
Dna replication
What happens during the G2 phase of interphase?
cell prepares to divide by creating necessary proteins (enzymes) and storing energy
What happens during the M phase
the cell undergoes nuclear division to split the genetic information into two equal halves.
What are the subphases of the M phase?
Prophase, metaphase, anaphase, and telophase.
What is cytokinesis?
formation of two genetically identical daughter cells.
Which of the following is NOT a role of mitosis?
* (a) Reproduction of unicellular eukaryotes *
(b) Development
* (c) Production of gametes
* (d) Tissue renewal
C) production of gametes
What is the difference between a haploid cell and a diploid cell?
(a) A haploid cell has one copy of each chromosome; a diploid cell has two copies of each chromosome.
(b) A haploid cell is involved in sexual reproduction; a diploid cell is involved in asexual reproduction.
(c) A haploid cell is a somatic cell; a diploid cell is a gamete. * (d) A haploid cell is produced by mitosis; a diploid cell is produced by meiosis.
Which of the following statements about the genome is FALSE?
a) The genome is the entirety of the genetic material in a cell. (b) Prokaryotes generally have a single circular chromosome.
* (c) Eukaryotes generally have multiple linear chromosomes in the nucleus.
* (d) The genome of eukaryotes is only found in the nucleus.
D
During which phase of the cell cycle is DNA replicated?
* (a) G1 phase * (b) S phase * (c) G2 phase * (d) M phase
B
What is the name of the structure that joins two sister chromatids? * (a) Centromere * (b) Kinetochore * (c) Chromosome * (d) Chromatin
A
Which of the following events does NOT occur during prophase?
(a) Chromosomes begin to condense
(b) Nucleoli disappear
(c) The nuclear membrane fragments and dissociates
(d) Centrosomes begin migration to poles
C
During which phase of mitosis do chromosomes line up on the metaphase plate? * (a) Prophase * (b) Metaphase * (c) Anaphase * (d) Telophase
B
What happens during anaphase? *
(a) Chromosomes begin to condense *
(b) Chromosomes line up on the metaphase plate *
(c) Sister chromatids detach from one another, and daughter chromosomes move to opposite poles of the cell. *
(d) Daughter nuclei form in the cell.
C
Which of the following statements about cytokinesis is TRUE? (a) Cytokinesis occurs before mitosis.
(b) Cytokinesis results in the division of the nucleus.
(c) Cytokinesis is the final stage of the cell cycle.
(d) Cytokinesis overlaps with telophase.
D
Which of the following statements about cytokinesis is TRUE? (a) Cytokinesis occurs before mitosis.
(b) Cytokinesis results in the division of the nucleus.
(c) Cytokinesis is the final stage of the cell cycle.
(d) Cytokinesis overlaps with telophase.
D
What is the role of the mitotic spindle?
* (a) To replicate DNA
* (b) To direct the movements of chromosomes during replication.
* (c) To divide the cytoplasm between daughter cells
* (d) To regulate the cell cycle
B
Which of the following is NOT a type of microtubule found in the mitotic spindle? *
(a) Aster microtubules
(b) Nonkinetochore microtubules
(c) Centromere microtubules
(d) Kinetochore microtubules
C
What is the function of kinetochore microtubules? *
(a) To help align the chromosomes on the metaphase plate and pull daughter chromosomes to poles. *
(b) To provide stability to the mitotic spindle by anchoring it to the cell membrane.
- (c) To overlap each other at the metaphase plate and lengthen the cell during anaphase.
- (d) To form the centromere.
A
What is the name of the protein structure that assembles at specific chromosome sequences of the centromere and serves as the site of kinetochore microtubule attachment to the chromosome?
- (a) Kinetochore * (b) Centromere * (c) Chromatid * (d) Chromosome
A
During which stage of mitosis do the centrosomes migrate to opposite poles? *
(a) Prophase and prometaphase *
(b) Metaphase and anaphase *
(c) Anaphase and telophase *
(d) Telophase and cytokinesis
A
When do the cohesins holding sister chromatids together cleave?
* (a) Prophase *
(b) Prometaphase
* (c) Metaphase *
(d) Anaphase
D
T/f
Mitosis is a type of cell division that results in four genetically unique daughter cells
False
T/f
The genome of prokaryotes is typically organized as a single circular chromosome.
True
T/f
Sister chromatids are joined at the kinetochore.
False
T/f
Centrosomes are essential for the formation of spindle microtubules.
False
T/f
Centrosomes are essential for the formation of spindle microtubules.
False
T/f
Kinetochore microtubules attach to chromosomes and pull them apart during anaphase.
True
