1. The Cell Cycle

2. Chromatin
A combination of DNA and protein molecules

3. Chromosomes
As a cell prepares to divide, its chromatin fibers condense, becoming visible as a compact structure

4. Sister Chromatids
Two identical, joined copies of chromosomes

5. Centromere
The region where the two chromatids are joined tightly together

6. Crossing Over
The exchange of genetic material between homologous chromosomes

7. Spindle Apparatus (Fiber)
Involved in moving and separating chromosomes during nuclear division

8. Homologous Chromosomes
Two chromosomes of each matching pair; one inherited from each parent

9. Gametes
Sex cells – egg and sperm

10. Haploid
A cell with a single set of chromosomes
Sex cells – 23

11. Diploid
Contain two homologous sets of chromosomes
In humans – 46

12. The Cell Cycle
Consists of G1 phase, S phase, G2 phase, Mitosis, and Cytokinesis

13. G1 Phase
Cell is growing and performing normal functions

14. S Phase
Cell replicates its DNA

15. G2 Phase
Cell makes microtubules in preparation for cell division

16. Interphase
G1, S, and G2 phases combined

17. Mitosis
Chromosomes move to opposite poles of the cell. Nucleus divides.

18. Cytokinesis
Cytoplasm divides. Two daughter cells are formed