HW # 57- Begin Cornell Notes, Chapter 4, Section 3 p. 129-134

Warm up How do cells grow and divide?

Week 18, Day One

Warm up Response

-The Cell Cycle, Mitosis, Meiosis

Homework Response/CheckD

Goals for Today

• KWL- Discuss Cell Division

How & Why Cells DivideCell Division can be broken up into 2 categories:

• Produce new cells, IDENTICAL to the original

MITOSIS

• Produce new cells, with HALF of the information of the original

MEIOSIS

Why Cells Divide20 µm100 µm 200 µm

(a) Reproduction. An amoeba, a single-celled eukaryote, is dividing into two cells. Each new cell will be an individual organism (LM).

(b) Growth and development. This micrograph shows a sand dollar embryo shortly after the fertilized egg divided, forming two cells (LM).

(c) Tissue renewal. These dividing bone marrow cells (arrow) will give rise to new blood cells (LM).

Mitosis Mitosis Mitosis

How Cells Divide:The Cell Cycle

• The cell cycle consists of– Interphase – normal cell activity– The mitotic phase – cell division

INTERPHASE

Growth

G 1

(DNA synthesis)

Growth

G2

Cel

l Div

sion

• DNA- contains all of the information that your cell needs (kind of like a textbook)

Animated Mitosis Cyclehttp://www.cellsalive.com/mitosis.htm

• Interphase

• Prophase

• Metaphase

• Anaphase

• Telophase

• Cytokinesis

Begin work on your Cornell Notes