BIOL 211 - CELLULAR AND ORGANISMAL BIOLOGY

Lecture Outline for February 21, 2005

 

 

Topics: binary fission, cell cycle, mitosis

Chapter 8 sections 8.1, 8.2

Figures used in lecture: 8.2, 8.4, 8.5, 8.6, 8,7, 8.8, 8.9

Additional resources

Mitosis Animation shown in class on Friday Feb 25

Eukaryotic Chromosome Structure

Cell Division – Binary Fission and Mitosis

Mitosis animation – A very good tutorial.  Requires Shockwave.

The Cell Cycle

Mitosis

Stages of mitosis – diagrams

Stages of mitosis – photographs

Mitosis vs meiosis - animated

 

 

Prokaryotic Cell Division

Define/explain: chromosome, binary fission

What is the structure of the chromosome in a prokaryotic cell?

What are the steps of binary fission?

 

Eukaryotic Chromosomes

Define/explain: chromatin, centromere, telomere

What is the structure of chromosomes in a eukaryotic cell?

Explain the difference between chromatin and chromosome.

 

Cell Cycle

Define/explain: mitosis, interphase, G1, S, G2, DNA replication, sister chromatid

Explain each step of the cell cycle and know what happens in each stage.

Understand the difference between a chromosome and sister chromatids.

 

Mitosis

Define: mitosis, parent nucleus, daughter nuclei, parent cell,  daughter cells,  asexual reproduction, centrosomes, prophase, metaphase, anaphase, telophase, spindle, microtubules,  kinetochore, equatorial plate (metaphase plate)

 

Mitosis ensures the accurate distribution of the multiple eukaryotic chromosomes to the daughter nuclei.  A single parent nucleus gives rise to two daughter nuclei that are genetically identical to each other and to the parent nucleus.  This is asexual reproduction.

 

Be able to place the steps of mitosis in the proper sequence.  Be able to describe with words or diagrams all events that occur in each step of mitosis.  If you are given a figure or a diagram, be able to identify the mitotic stage the cell is in.  You should have a clear understanding of the purpose of mitosis and how the process accomplishes this purpose.

 

Cytokinesis

Define/explain: cytokinesis, cleavage furrow, cell plate

Be able to describe the process of cytokinesis in both plant and animal cells.

 

Today’s Lecture (2-21-05)

Cell cycle

Mitosis

 

Prokaryotic Cell Division

no nucleus; single, circular chromosome of DNA

Bacterial cell division is asexual

binary fission - cell division process seen in prokaryotes

            1.  Chromosome replicates.

            2.  Chromosomes become attached to cell membrane.

            3.  As the cell grows, 2 copies of the chromosome separate from each other.

            4.  The center of the cell pinches in to separate 2 new cells.

 

Eukaryotic Cell Division

Chromosome structure:

Multiple, linear chromosomes; composed of chromatin

chromatin –

 

centromere –

 

telomere -

 

Cell cycle = life cycle of a cell

consists of

mitosis –

 

interphase -

 

Interphase:

G1(gap 1):

 

S (synthesis):

 

G2(gap 2):

 

Mitosis is division of the nucleus.  It is the process by which new cells are generated.
Function: to create daughter cells identical to the parent cell

- for growth, development, repair of tissue,

- for production of new individuals in asexually reproducing organisms

 

Mitosis stages:

1.  Prophase

2.  Metaphase

3.  Anaphase

4.  Telophase