MCAT BIOLOGY 2.1 | CELL CYCLE & MITOSIS
REVIEW
1. genome: The aggregate of an organism's genetic information
2. chromosomes: A threadlike, gene-carrying structure found in the nucleus, Cell structures
that carry the genetic material that is copied and passed from generation to generation of cells; only
distinguishable from chromatin during cellular division; every eukaryotic species has a characteristic
number of these in their nucleus
3. several hundred to a few thousand: How many genes does a DNA molecule
contain?
4. chromatin: Clusters of DNA, RNA, and proteins found in the nucleus of a cell
5. somatic cells: Any cells in the body other than reproductive cells; contain 46 chromosomes,
23 from each parent
6. gametes: A haploid cell such as an egg or sperm; contain 23 chromosomes
7. a long, thin chromatin fiber: What does a chromosome look like when cell division is not
occuring?
8. a densely coiled and folded chromatin fiber; visible under a light
microscope-
: What does a chromosome look like when cell division is occuring?
9. centromere: The region of the chromosomal DNA where the two sister chromatids are most
closely bound; mediated by proteins bound to the centromeric DNA
10. mitosis: A process of nuclear division in eukaryotic cells conventionally divided into five
stages: prophase, prometaphase, metaphase, anaphase, and telophase; succeeded by cytokinesis
11. cytokinesis: The division of the cytoplasm during cell division; preceded by mitosis
12. meiosis: A type of cell division that produces reproductive cells in sexually reproducing
organisms
13. mitotic phase: Stage of the cell cycle when a cell is actively dividing; includes mitosis and
cytokinesis; less than an hour in length in human cells
14. interphase: The period between two mitotic or meiotic divisions during which the cell grows,
copies its DNA, and synthesizes proteins; represents 90% of a cell's life cycle
15. G1 phase: A subphase of cellular interphase referred to as the "first gap"; the cell
experiences growth in this stage; 5-6 hours in lengh in human cells (although this phase is the most
variable in length in ditterent cells)
16. S phase: A subphase of cellular interphase referred to as the "synthesis"; the cell grows
more while it copies its chromosomes in this stage; 10-12 hours in lengh in human cells
17. G2 phase: A subphase of cellular interphase referred to as the "second gap"; the cell
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10
, MCAT BIOLOGY 2.1 | CELL CYCLE & MITOSIS
REVIEW
continues to grow while it completes preparation for cellular division in this phase; 4-6 hours in lengh
in human cells
18. 24 hours: How long does it take for a typical human cell to undergo division?
19. prophase: In this stage of mitosis:
• The chromatin fibers become more tightly coiled, condensing into discrete chromosomes observable
with a light microscope.
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10
REVIEW
1. genome: The aggregate of an organism's genetic information
2. chromosomes: A threadlike, gene-carrying structure found in the nucleus, Cell structures
that carry the genetic material that is copied and passed from generation to generation of cells; only
distinguishable from chromatin during cellular division; every eukaryotic species has a characteristic
number of these in their nucleus
3. several hundred to a few thousand: How many genes does a DNA molecule
contain?
4. chromatin: Clusters of DNA, RNA, and proteins found in the nucleus of a cell
5. somatic cells: Any cells in the body other than reproductive cells; contain 46 chromosomes,
23 from each parent
6. gametes: A haploid cell such as an egg or sperm; contain 23 chromosomes
7. a long, thin chromatin fiber: What does a chromosome look like when cell division is not
occuring?
8. a densely coiled and folded chromatin fiber; visible under a light
microscope-
: What does a chromosome look like when cell division is occuring?
9. centromere: The region of the chromosomal DNA where the two sister chromatids are most
closely bound; mediated by proteins bound to the centromeric DNA
10. mitosis: A process of nuclear division in eukaryotic cells conventionally divided into five
stages: prophase, prometaphase, metaphase, anaphase, and telophase; succeeded by cytokinesis
11. cytokinesis: The division of the cytoplasm during cell division; preceded by mitosis
12. meiosis: A type of cell division that produces reproductive cells in sexually reproducing
organisms
13. mitotic phase: Stage of the cell cycle when a cell is actively dividing; includes mitosis and
cytokinesis; less than an hour in length in human cells
14. interphase: The period between two mitotic or meiotic divisions during which the cell grows,
copies its DNA, and synthesizes proteins; represents 90% of a cell's life cycle
15. G1 phase: A subphase of cellular interphase referred to as the "first gap"; the cell
experiences growth in this stage; 5-6 hours in lengh in human cells (although this phase is the most
variable in length in ditterent cells)
16. S phase: A subphase of cellular interphase referred to as the "synthesis"; the cell grows
more while it copies its chromosomes in this stage; 10-12 hours in lengh in human cells
17. G2 phase: A subphase of cellular interphase referred to as the "second gap"; the cell
1/
10
, MCAT BIOLOGY 2.1 | CELL CYCLE & MITOSIS
REVIEW
continues to grow while it completes preparation for cellular division in this phase; 4-6 hours in lengh
in human cells
18. 24 hours: How long does it take for a typical human cell to undergo division?
19. prophase: In this stage of mitosis:
• The chromatin fibers become more tightly coiled, condensing into discrete chromosomes observable
with a light microscope.
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10
