1. Cell Division
Chapter 10

2. Cell Limitation As Cell Grows: Stops growing before too large
It divides, forming two cells

3. Cell Division
Process by which the cell divides into two new daughter cells.

4. Chromosomes
Carries genetic information that is passed from one generation of cells to the next
DNA
only visible during cell division
every organism has a specific number

5. Terms Sister Chromatids: two identical copies of the chromosome
Centromeres: attaches the chromatids together.

7. Cell Cycle
series of events that cells go through as they grow and divide
Interphase: period of the growth of the cell
M phase

8. Interphase Divided into three phases: G1 (growth)
S (replication of DNA)
G2 (preparation for mitosis)

9. Mitosis Divided into four phases: Prophase Metaphase Anaphase
telophase

10. Prophase Chromatin condenses Centrioles separate
Spindle begins to form
Nuclear envelope breaks down

11. Metaphase Chromosomes line up across center
Spindle fiber connected to centromere

12. Anaphase Sister chromatids separate into chromosomes
Sister chromatids move apart

13. Telophase Chromosomes gather at opposite ends
Chromosomes lose distinct shape
2 nuclear envelopes form

14. Cytokinesis (splitting into two)
occurs at the same time as telophase.
Animals: The cell membrane is drawn inward until it is pinched into
Plants: cell plate forms midway between the cell

15. Cell Cycle Regulators
Tells cells when it is time to divide and duplicate chromosomes
Cyclin: protein that regulates the timing of the cell cycle in eukaryotic cells
Two different types:
Internal Regulators
External Regulators

16. Internal Regulators Proteins that respond to events inside the cell
Allow the cell cycle to proceed only when certain processes have happened inside the cell.
EX: some regulators make sure that a cell does not enter mitosis until all its chromosomes have been replicated.

17. External Regulators Proteins that respond to events outside the cell
Direct cells to speed up or slow down the cycle.
Growth factors: stimulate the growth and division of cells.
Prevent extensive cell growth and keep the tissues of the body from disrupting each other

18. Uncontrolled Cell Growth
Cancer:
cells lose the ability to control
growth.
Does not respond to the signals
that regulate the growth
Form tumors

19. Benign: not cancerous
Malignant: Cancerous

20. Meiosis
Terms:
Homologous: each of the chromosomes that come from the male parent and female parent.
Diploid (2N): contains both sets of homologous chromosomes (two sets).
Haploid (N): contains only a single set of chromosomes (single set)

21. Meiosis the number of chromosomes is cut in half
Two cell divisions: Meiosis I and Meiosis II
End Result: 4 haploid cells

22. Meiosis I
Interphase I
Prophase I: chromosomes pair with its corresponding homologous chromosome
Crossing over
Metaphase I, Anaphase I, Telophase I

24. Meiosis II second meiotic division
Prophase II: Neither cell goes through a round of chromosome replication
Metaphase II, Anaphase II, Telophase II

26. Gamete Formation: Males: sperm Females: eggs
Produces 4 haploid sperm cells
Females: eggs
Produces 1 haploid egg cell
Receives most of the cytoplasm
Polar bodies

27. Mitosis and Meiosis Results: two genetically identical diploid cells
Begins with a diploid cells and ends with a diploid cell
Involved in asexual reproduction
Results: four genetically different haploid cells.
Begins with a diploid cell and ends with a haploid cell
Involved in sexual reproduction