Notes: Life of a Cell

Part 2: Cell Reproduction

Cell Reproduction

• According to the CELL THEORY, all CELLS come from PREEXISTING cells and have the capability of reproducing

• Life is based on the reproduction of cells or “CELL DIVISION”

I. What is Cell Division?

• PRODUCTION of DAUGHTER cells

II. What will happen because of cell division?• GROWTH and DEVELOPMENT: because

of an increase in cell number, cell size, and cell products, the organism grows in stages and shows developmental difference.

III. Two Types of Cell Division

Asexual Sexual

Set up a table Or tree map in space provided

Asexual

• Mother cell reproduces 2 IDENTICAL daughter cells

• Example: MITOSIS• Types of cells reproduced: body cells

(somatic)• Happens in both Eukaryotic and

Prokaryotic cells

Sexual

• After sperm and egg are produced, fusion of these cells produces a non-identical cell

• Example: Meiosis• Types of cells produced: sperm/egg• Only in Eukaryotic cells

IV. Eukaryotic Cell Division – Up Close

A. The CELL CYCLE: events of the cell that happen before, during, and after cell division

o THREE special events: Interphase (I), Mitosis (M), and Cytokinesis (C)

1. Interphase (I): 70-90% of cell’s life

• NO active cell division

• 3 phases: G1, S, G2

Make an Interphase flow map on the bottom of your paper:

Interphase

• 3 Phases

G1

• Growth• Metabolic

processes

S Phase

• DNA copies

G2

• Final growth

2. Mitosis (PMAT): DIVISION of the cell’s NUCLEUS

• Separation of CHROMOSOMES in a series of processes

• Resulting cell has 2 new NUCLEI• 4 distinct phases: PMAT

3. Cytokinesis (C): final DIVISION of the Cell’s CYTOPLASM

• 2 new DAUGHTER cells (Identical)• Animal cells pinch or cleave into 2 cells• Plant cells separate as new cell wall divides

the 2 cells

Mitosis Flow Map: