1. Cell Growth and Reproduction in EUKARYOTES

2. What is a Eukaryotic Cell?
Cell that HAS nucleus
Contains double stranded DNA
Animal and plant cells!!

3. DNA DNA provides the blueprints or instructions for protein synthesis.
Cells cannot survive unless there is enough DNA to support the protein needs of the cell.

4. Cell Reproduction
The cell theory states that “all cells come from pre-existing cells.”
Cell division is the process by which this happens!
Cell division results in two cells that are identical to the original parent cell.
All organisms grow and change; worn out tissues are repaired or replaced by newly produced cells!

5. Before we learn about division, lets start with the BASICS!
What is “Genetic Material”? – DNA
Where do we find DNA? – The cell nucleus

6. So what the heck is a chromosome?!
Chromosome- Tightly coiled strands of DNA
Where are chromosomes found? – THE NUCLEUS!

7. Parts of the chromosome
Each chromosome has 2
CHROMATIDS
Each chromosome has
1 CENTRIOLE holding both
Chromatids together

8. How many chromosomes in a cell!?
Humans have 46 total chromosomes
23 pairs of chromosomes

9. What is MITOSIS? The process of the cell dividing ASEXUALLY
Only ONE PARENT is needed
One PARENT CELL
splits into TWO
DAUGHTER CELLS
Both daughter cells have
IDENTICAL DNA to parent cell

10. Let’s make like hairs and SPLIT

11. Phase 1: INTERPHASE Interphase contains 3 stages! 3 stages
G1 – Cell grows rapidly and protein production is high
S – Cell copies its chromosomes and DNA synthesis occurs
G2 – Short growth period in which mitochondria and other organelles are made and parts needed for cell division (centrioles) are manufactured

12. INTERPHASE

13. Interphase During this phase, the cell copies its
DNA in preparation for the division.

14. Phase 2: PROPHASE PROPHASE – longest phase of mitosis
Chromatin (DNA strands) coil up into visible chromosomes
They look kind of hairy!
Each chromosome is made of two identical halves called SISTER CHROMATIDS
These halves are held together by a CENTROMERE

15. PROPHASE

16. PROPHASE CONTINUED…
As prophase continues, the nucleus begins to disappear as the nuclear envelope and the nucleolus disintegrate.
At this time, the CENTRIOLES begin to migrate to opposite poles of the cell
The SPINDLE begins to form between the centrioles.
“Chromosomes PREPARE for division”

17. What the heck is a centriole?
A small set of microtubules
Contain SPINDLE FIBERS
Centrioles are found in pairs and travel in pairs
Centrioles travel to opposite poles of the nucleus to begin the divison process

18. PROPHASE CONTINUED…
CENTRIOLES
SPINDLE FIBERS

19. METAPHASE
The chromosomes begin to line up on the midline or equator of the spindle
The spindle fibers of the centrioles become attracted to the centromeres of chromosomes (middle of chromosomes
“Spindle fibers MEET the centromeres”

20. METAPHASE

21. ANAPHASE 3) ANAPHASE – Third phase of mitosis
Spindle fibers pull the chromosomes
Sister chromatids begin to separate
Centromeres split apart and the chromatids are pulled apart
“Split from Annie”

22. TELOPHASE Chromatids are pulled to opposite poles of the cell
Nucleolus reappears and new nuclear envelope forms around each new set of chromosomes
New double membrane begins to form between two new nuclei

23. TELOPHASE

24. CYTOKINESIS
The cell’s cytoplasm finally divides and the cell starts to pinch along the equator of the cell forming two new cells!
“Cytokinesis, division of cytoplasm”

25. Overview