2. Activating Prior Knowledge:
List the eight characteristics of living things.
List four differences between plant and animal cells.
Which animal organelle is used in cell division?
Which organelle surrounds the cell membrane in plant cells?
What do we call the jelly-like material within the cell?
What are chromosomes made of?
Where are chromosomes found in your cell (organelle)?
How many chromosomes are found in each human body cell?
Where did YOUR chromosomes come from?
Can you name five types/kinds of cells found in the human body?
Name three differences between prokaryotic and eukaryotic cells.

3. Do you remember any of the eight characteristics of living things?
Living things are based on a universal genetic code (DNA)
Living things grow and develop
Living things respond to their environment (stimulus)
Living things reproduce
Living things maintain a stable internal environment (homeostasis)
Living things obtain and use material and energy (metabolism)
Living things are made up of CELLS
Taken as a group, living things evolve over time

4. Plant vs. Animal Cell wall and cell membrane Large central vacuole
Chloroplast (photosynthesis) and mitochondria (cellular respiration)
Only a cell membrane
Smaller vacuoles
Only mitochondria (cellular respiration)
Lysosomes
Flagella
Centrioles – used in cell division

5. Chromatin and Chromosomes:
Inside the nucleus are fine strands of chromatin = a complex of DNA bound to protein
Chromatin coil up and become densely packed, forming chromosomes
Chromosomes are visible under a microscope when a cell divides

6. Number of chromosomes in a human body cell?
23 pairs of chromosomes = 46 chromosomes total
23 from mom and 23 from dad

7. Where are chromosomes in eukaryotic cells?
CYTOPLASM
NUCLEUS

8. Types of Cells in the body:
Cells - basic unit of structure and function in living things
Cells with a specific structure and function and are found in multi-celled organisms
Examples: skin cells, blood cells, brain cells, bone cells, liver cell, nerve cells, muscle cells, etc.
Brain cells
Blood cells
Liver cells

9. Two categories of cells
Prokaryotic
Eukaryotic
-Nucleus
-Unicellular
-No Nucleus
-Complex
-Cell wall (plants and bacteria)
-Membrane bound organelles
-Less complex
-Smaller Ribosomes less complex
-Cell membrane
-Multicellular
-DNA
- Ribosomes larger and complex
-Cytoplasm
-DNA is circular
-Ribosomes
-DNA is X shaped
-Living things
0.1-10µm
10-100µm

10. Vocabulary: Asexual Reproduction Sexual Reproduction Mitosis Meiosis
Diploid
Haploid
Chromatin
Chromatid
Centromere
Histone
Nucleosomes

11. Asexual Reproduction:
The production of genetically identical offspring from a single parent

12. Sexual Reproduction:
Offspring are produced by the fusion of two sex cells – one from each of two parents. These fuse into a single cell before the offspring can grow.

13. Mitosis: Division of the nucleus of a eukaryotic cell
Followed by cytokinesis –
division of the cytoplasm
The two daughter cells are
identical to the original cell

14. Meiosis:
Process that produces gametes from a diploid cell. A reductive division of the nucleus that produces four haploid gametes.

15. Diploid: Cells having two sets of chromosomes 2N = 46
Examples: All human body cells
Except reproductive cells (sperm and egg)

16. Haploid: Cells containing only one set of chromosomes N = 23
Gametes (egg and sperm)

17. Chromatin:
DNA and protein (histones) in the nucleus of a non-dividing cell

18. Chromatid:
One of the two identical parts of a replicated chromosome

19. Centromere:
Point of attachment between sister chromatids

20. Histone:
Protein molecule that DNA wraps around during chromosome formation

21. Cellular Reproduction
Section 1: Cellular Growth
Section 2: Mitosis and Cytokinesis
Section 3: Cell Cycle Regulation

22. Nucleosomes:
The beadlike structures formed by DNA and histone molecules

23. Ratio of Surface Area to Volume
Section 1
Cellular Reproduction
Cellular Growth
Ratio of Surface Area to Volume

24. Section 1
Cellular Reproduction
Cellular Growth
As the cell grows, its volume increases much more rapidly than the surface area.
The cell might have difficulty supplying nutrients and expelling enough waste products.

25. Transport of Substances
Section 1
Cellular Reproduction
Cellular Growth
Transport of Substances
Substances move by diffusion or by motor proteins.
Diffusion over large distances is slow and inefficient.
Small cells maintain more efficient transport systems.

26. Cellular Communications
Section 1
Cellular Reproduction
Cellular Growth
Cellular Communications
The need for signaling proteins to move throughout the cell also limits cell size.
Cell size affects the ability of the cell to communicate instructions for cellular functions.

27. Cell division prevents the cell from becoming too large.
Section 1
Cellular Reproduction
Cellular Growth
The Cell Cycle
Cell division prevents the cell from becoming too large.
It also is the way the cell reproduces so that you grow and heal certain injuries.
Cells reproduce by a cycle of growing and dividing called the cell cycle.

28. Section 1
Cellular Reproduction
Cellular Growth
Interphase is the stage during which the cell grows, carries out cellular functions, and replicates.
Mitosis is the stage of the cell cycle during which the cell’s nucleus and nuclear material divide.
Cytokinesis is the method by which a cell’s cytoplasm divides, creating a new cell.

29. The Stages of Interphase
Section 1
Cellular Reproduction
Cellular Growth
The Stages of Interphase
The first stage of interphase, G1
The cell is growing, carrying out normal cell functions, and preparing to replicate DNA.

30. G0 Phase
Not all cells are continually replicated.
Example: nerve cells, heart cells
Cells enter G0 from G1
Nonreplicating cells are found in G0 – quiescent (dormant) or senesecent (aging or deteriorating)
Do NOT copy their DNA, do NOT prepare for cell division
Cells may remain quiescent in G0 for an indeterminate period of time (when no more new cells are needed), only to re-enter G1 phase and begin dividing again under specific conditions.

31. The Second Stage of Interphase, S
Section 1
Cellular Reproduction
Cellular Growth
The Second Stage of Interphase, S
The cell copies its DNA in preparation for cell division.

32. The Third Stage of Interphase, G2
Section 1
Cellular Reproduction
Cellular Growth
The Third Stage of Interphase, G2
The cell prepares for the division of its nucleus.

33. The chromosomes condense.
Section 2
Cellular Reproduction
Mitosis and Cytokinesis
The Stages of Mitosis
Prophase
The chromosomes condense.
Sister chromatids are attached at the centromere.
The longest stage of mitosis
Spindle fibers form in the cytoplasm.
The nuclear envelope seems to disappear.
Spindle fibers attach to the sister chromatids.

35. Sister chromatids line up in the middle of the cell.
Section 2
Cellular Reproduction
Mitosis and Cytokinesis
Metaphase
Sister chromatids line up in the middle of the cell.
The shortest stage of mitosis

36. The sister chromatids separate.
Section 2
Cellular Reproduction
Mitosis and Cytokinesis
Anaphase
The sister chromatids separate.
The chromosomes move toward the poles of the cell.

37. The chromosomes arrive at the poles and begin to relax.
Section 2
Cellular Reproduction
Mitosis and Cytokinesis
Telophase
The chromosomes arrive at the poles and begin to relax.
Two new nuclear membranes begin to form and the nucleoli reappear.
The spindle apparatus disassembles.

38. Cytokinesis in Animal Cells
In animal cell, cell membrane is drawn in (forming a cleavage furrow) until the cytoplasm is pinched into two equal parts.
Each part contains its own nucleus and organelles.

39. Cytokinesis in Plant Cells
TEM 7,500
Cell plate forming
Wall of parent cell
Daughter nucleus
Cell wall
New cell wall
Vesicles containing cell wall material
Cell plate
Daughter cells
Plant Cells
In plants, the cell membrane is not flexible enough to draw inward because of the rigid cell wall.
A cell plate forms between the divided nuclei that develops into cell membranes.
A cell wall then forms in between the two new membranes.

40. Telophase and Cytokinesis

42. Section 3:Cell Cycle Regulation

43. Regulating the Cell Cycle
Cell growth and division are very controlled
True or False – All cells move through the cell cycle at the same rate.
The average human cell cycle is about 20 hours.
Most muscle and nerve cells do not divide once they have developed
Blood, skin and digestive tract cells divide rapidly throughout life

44. What is the protein called? cyclin Why? regulates cell cycle
Section 3
Cellular Reproduction
Cell Cycle Regulation
Normal Cell Cycle
Scientists have been trying to determine what regulates the cell cycle.
Biologists discovered a protein that when injected into a non-dividing cell, a mitotic spindle would form.
What is the protein called? cyclin
Why? regulates cell cycle
Cyclins regulate the timing of the cell cycle in eukaryotic cells.

45. Cell Cycle

46. Quality Control Checkpoints
Section 3
Cellular Reproduction
Cell Cycle Regulation
Quality Control Checkpoints
The cell cycle has built-in checkpoints that monitor the cycle and can stop it if something goes wrong.
Spindle checkpoints also have been identified in mitosis.

47. Cell Cycle Checkpoints

48. Abnormal Cell Cycle: Cancer
Section 3
Cellular Reproduction
Cell Cycle Regulation
Abnormal Cell Cycle: Cancer
Cancer is the uncontrolled growth and division of cells.
Cancer cells can kill an organism by crowding out normal
cells, resulting in the loss of tissue function.

49. Section 3
Cellular Reproduction
Cell Cycle Regulation
Causes of Cancer
The changes that occur in the regulation of cell growth and division of cancer cells are due to mutations.
Various environmental factors can affect the occurrence of cancer cells.

50. Apoptosis Programmed cell death
Section 3
Cellular Reproduction
Cell Cycle Regulation
Apoptosis
Programmed cell death
Cells going through apoptosis actually shrink and shrivel in a controlled process.

51. Section 3
Cellular Reproduction
Cell Cycle Regulation
Stem Cells
Unspecialized cells that can develop into specialized cells when under the right conditions

52. Section 3
Cellular Reproduction
Cell Cycle Regulation
Embryonic Stem Cells
After fertilization, the resulting mass of cells divides repeatedly until there are about –150 cells. These cells have not become specialized.

53. Section 3
Cellular Reproduction
Cell Cycle Regulation
Adult Stem Cells
Found in various tissues in the body and might be used to maintain and repair the same kind of tissue
Less controversial because the adult stem cells can be obtained with the consent of their donor