Stages of mitosis final project itp

Stages of Mitosis

Kimberly J. Luper B.S. M.S.

Objectives

Distinguish the difference between mitosis and meiosis.

List the functions of mitosis

Define the mitotic phase.

Discuss and explain the four stages of mitosis.

Define cytokinesis.

Mitosis v/s Meiosis

• Mitosis is the duplication of the chromosomes in the nucleus and their separation into two identical sets in the process of somatic (“of the body”) cell division.

• Meiosis is restricted to one purpose, the production of eggs and sperm.

Functions of Mitosis

Growth of all tissues and organs after birth.

Replacement of cells that die.

Repair of damaged tissues.

Mitotic Phase

The mitotic phase of the cell cycle consists of: Nuclear division

(mitosis)

Cytoplasmic division (cytokinesis) to form two identical cells.

Four Stages of Mitosis

Prophase

Prophase is actually divided into two steps:

1. Early prophase

2. Late prophase

Early Prophase

Centrioles(two pairs) “Aster rays”

Nuclear envelope containingchromosomes.

Late Prophases

Chromosome withtwo sisters chromatids

Centromere

Centrioles

Spindle fibers /microtubules

Metaphase

Metaphase plate

Chromosomemicrotubules

Anaphase

Daughter chromosomes

Telophase

Cleavage furrow

Nuclear membranes

Cytokinesis

Daughter cells

Cytokinesis

Cytoplasmic division: contractile ring from cleavage furrow around the center of the cell, dividing cytoplasm into separate and equal portions.

WHY?

Why is the mitotic phase or mitosis phase so important?

WHY?

Cell division or mitosis helps the body to replace dead cells and repair damaged tissue.

(Paper cuts to major surgery)

Check In

PMAT

PMAT

1. Pro(before) phase: Chromatin fibers condense into paired chromatids; nucleus envelope disappears; each centrosome moves to an opposite pole of the cell.

2. Meta( after) phase: Centromeres of chromatid pairs line up at metaphase plate.

PMAT

3. Ana(apart) phase: Centromeres split; identical sets of chromosomes move to opposite poles of the cell.

4. Telo(end) phase: Nuclear envelopes and nucleoli reappear; chromosomes resume chromatin form; mitotic spindles disappear.

References

Tortora, G.J. & Derrickson, B. (2012). Principles of Anatomy and Physiology (13th ed.). Hoboken, NJ: John Wiley & Sons.

Martini, F.H., Nath, J.L. (2012) Fundamentals of Anatomy & Physiology (9th ed.). San Francisco, C.A. Pearson Education, Inc.