Teacher: Ma Ching ManCourse: Course for secondary school teachers on

teaching science education KLA in the English mediumCourse date: 16/6/2014-20/6/2014

Teaching plan: (Biology) Mitotic cell divisionTarget group: S4 students

Mitotic cell division

Cell growth

Cell division

Revision: Cell cycle

first growth phase

Cell cycle

G1

• new organelles made, e.g.:

– mitochondria

– chloroplasts

• proteins made

synthesis phase

Cell cycle

S• DNA replicates

G2

• stores of energy increase

• cell grows to maximum size

second growth phase

Cell cycle

Cell division

Mitotic cell division Meiotic cell division

Cell division

Stage 2: cytoplasmic division

Two stages in mitotic cell division

Stage 1: nuclear division

Mitotic cell division

There are 4 phases in this stage.

1 Prophase

chromosome appears as two chromatids

nuclear membrane disintegrates

Mitotic cell division

Nuclear division (4 phases)

pro- comes from proto- meaning first

What forms do the chromosomes take?

Mitotic cell division

1 Prophase

chromosomes line up in the middle

Mitotic cell division

2 Metaphase

meta- means after or next

Where are the chromosomes located?

Mitotic cell division

2 Metaphase

chromatids separate and move to opposite poles

cytoplasm starts to divide

Mitotic cell division

3 Anaphase

ana- means again or repeated

What happens to the chromosomes?

Mitotic cell division

3 Anaphase

nuclear membranes form

Mitotic cell division

chromosomes uncoil to become chromatin

4 Telophase

telo- comes from telos meaning last or final

Mitotic cell division

What happens to the chromosomes?

4 Telophase

animal cells

The cell membrane constricts inwards, forming two genetically identical cells.

cell membrane

Cytoplasmic division

Mitotic cell division

plant cells

The cell plate, which grows outwards and divides the cell.

Mitotic cell division

Class activity: “Ice-bar stick” model

Task

Use the sticks to demonstrate and explain the stages and phases to your classmates.

Mitotic cell division

chromatids

chromosome

Class activity: “Ice-bar stick” model

ice-bar sticks

represent

Prophase

chromosome appears as two chromatids

nuclear membrane disintegrates

chromosomes line up in the middle

Metaphase

sister chromatids separate and move to opposite poles

cytoplasm starts to divide

Anaphase

chromosomes uncoil to become chromatin

nuclear membranes form

Telophase

Video

Task

To identify the stages and phases from the video.http://www.youtube.com/watch?v=aDAw2Zg4IgE&feature=related

cytoplasmic division

nuclear division

cell division

prophase

metaphase

anaphase

telophase

Summary

1. Observe the photomicrograph of cells in the onion root tip.

2. Identify the stages and phases.

Exercise: Examination of different stages and phases of mitotic cell division

ABCD

EF

GHI

JOnion root tip (L.S.)