1. https://www. youtube. com/watch

2. Cell Cycle
The sequence of growth and division of a cell

3. Why can’t most organisms be just one giant cell?

4. Diffusion becomes slow and inefficient as the distances become larger.
The cell would either starve to death or be poisoned from the buildup of waste products.

5. The majority of a cell’s life is spent in the period known as interphase.

6. Interphase – Cell is growing and DNA is replicated (copied)
It consists of
G1 phase - the cell grows and protein production is high
S phase - DNA is synthesized and copied
G2 phase –organelles are manufactured G1

7. After Interphase a cell divides. Cell division consists of
M phase = MITOSIS (nuclear division)
Cytokinesis G1

8. The end result of cell division are 2 new genetically identical cells are produced from one parent cell
Same DNA

9. DNA CAN BE: SPREAD OUT IN NON-DIVIDING CELLS (interphase) =
SCRUNCHED UP
IN DIVIDING CELLS (mitosis)=
CHROMATIN
CHROMOSOMES

13. Mitosis
Nuclear division

14. Phase 1: Prophase
Chromatin condenses - chromosomes are visible

15. Phase 2: Metaphase Chromosomes move to the equator
Spindle fibers attach to the centromeres (middle of chromosomes)

16. Phase 3: Anaphase centromeres split
sister chromatids are pulled apart to opposite poles of the cell.

17. Phase 4: Telophase
Two new nuclei are formed – nuclear membrane reappears

18. After mitosis…Cytokinesis
the cytoplasm divides (cytokinesis), separating the two new identical daughter cells

19. Cytokinesis in Animal Cells
plasma membrane pinches in forming 2 new separate cells.

20. Cytokinesis in Plant Cells
plasma membrane does not pinch in (because of rigid cell wall)
A cell plate forms across the cell’s equator…eventually forming a new cell wall.

24. Why is cell division beneficial?
In unicellular organisms cell division is used for reproduction (asexual)
Ex. Bacteria reproducing
In multicellular organisms cell division is used for growth and repair
Ex. Humans producing new skin cells

25. Asexual reproduction in unicellular organisms
offspring are genetically identical to parent – clones
no variation in the species
occurs in single-celled organisms
only one parent
achieved without fertilization

26. Types of asexual Reproduction
Binary fission
Budding
Sporulation
Regeneration
Vegetative propagation

27. 1. Binary Fission Cell splits into two identical daughter cells
Cytoplasm divides equally
Ex.:
Bacteria
Ameba
Paramecium

30. 2. Budding
one of the daughter cells develops as a smaller protrusion from the other
Unequal division of cytoplasm
Ex:
Hydra
Jelly fish
Yeast

32. 3. Sporulation
Parent releases hundreds of (spores) identical copies of itself
Spores are surrounded by a tough coat to help them survive harsh environmental conditions.
Ex:
Molds
mushrooms

35. 4. Regeneration
the replacement or regrowth of lost or damaged body parts
Ex:
usually invertebrates (exception are lizards)
sea stars
Crabs
Lobsters
Worms

37. 5. Vegetative Propagation
Occurs only in plants
New plants develop from the roots, stems, or leaves of the parent plant

38. Types of Vegetative Propagation
Cuttings (Grafting) - a plant part which is cut from the parent plant in order to regenerate itself, thereby forming a whole new plant.

39. Bulb Ex. Onion contains an underground stem.
As the plant grows and develops it will form a new bulb underground.
Ex. Onion

40. Tubers
New plants will grow out of swollen, modified roots called tubers.
Buds develop at the base of the stem and then grow into new plants.
Ex. Potato

41. Runner stems that grow horizontally above the ground.
They have nodes where buds are formed.
These buds grow into a new plant.
Ex. Strawberries

42. What is the advantage of sexual reproduction over asexual reproduction?
Genetic variation - Increased chance of survival in changing environment

43. Binary fission
Vegitative Propagation
Budding
Sporulation