Standard 2.6 Describe the cell cycle and the process of mitosis. Explain the role of mitosis in the formation of new cells, and its importance in maintaining chromosome number during asexual reproduction.
Vocabulary
Tier 3
Cell cycle - the life cycle of a cell
Interphase - when the cell is not reproducing
G1 phase
S phase
G2 phase
M phase
Chromosomes - X-shaped structures of DNA wrapped up around proteins
Homologous Pairs - chromosomes come in a pairs, one maternal and one paternal
Sister Chromatids - halfof the X chromosome
Sex chromosomes -XX is a girl; XY is a boy
DNA Replication - the DNA copies itself
Mitosis - cell division
prophase
metaphase
anaphase
telophase
Cytokinesis - dividing up the cytoplasm and organelles between two cells
Daughter cells - the two cells that are made during cell division
Essential Questions
1. What are the phases of the cell cycle?
2. When a cell goes through mitosis, how many chromosomes do the two daughter cells have?
3. What is happening during the stages of mitosis and cytokinesis?
4. How do homologous pairs differ from sister chromatids?
Cell cycle:
All cells are either in interphase of m phase
a. Interphase consists of G1, S and G2 phases
During G1 the cell is little and growing
During S the DNA is copied
During G2 the cell is getting ready to reproduce
b. Mitosis is the division of cells
Prophase, Metaphase, Anaphase Telophase and Cytokinesis
*Mitosis always ends with the same number of chromosomes it begins with
46--------->46
a. Interphase consists of G1, S and G2 phases
During G1 the cell is little and growing
During S the DNA is copied
During G2 the cell is getting ready to reproduce
b. Mitosis is the division of cells
Prophase, Metaphase, Anaphase Telophase and Cytokinesis
*Mitosis always ends with the same number of chromosomes it begins with
46--------->46
M Phase or Mitosis:
Cells divide. The number of chromosomes stays the same for each cell.
Cell Reproduction
I. Chromosomes: During cell division, the cell's DNA winds up into X shaped structures
Every species has a certain amount of chromosomes. We have 46. Almost every cell in your body has 46 chromosomes. The first 22 pairs are called autosomal and the last pair are the sex chromosomes. The sex chromosomes determine your gender.
**Some people do not have 46 chromosomes, they have 47. This is a chromosomal disease like Down's Syndrome or Kleinfelter's. People with Downs have 3 chromosomes on chromosome pair 21. People with Kleinfelter's have XXY for sex chromosomes