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Starter

Name as many parts of plant and animal cells as you can.
Which part controls the cell?

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Starter

You all started life as a single cell, a fusion of the sperm and the egg.

What is the name of that cell?

What is the name of the process that must have happened to create you from that single cell?

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Starter

How many new cells do you think you will make in a day?

23,760,000,000 new cells every day!

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Cell Division

Unit 1 Key Area 1: Cell Division

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Learning Intention: To investigate how cells divide

Success Criteria

I can explain why it is important cells can divide

I can describe the process of mitosis.

I can discuss the importance of maintaining a chromosome complement.

I can state what happens if cell division is not controlled.

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Parts of a cell

You need to know the functions of several parts of a cell:

Nucleus - controls the cell activities, contains DNA

Mitochondria - site of respiration, where cells gain energy

Ribosome - site of protein production

Chloroplast - site of photosynthesis

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Cell Structure

Cell Membrane

Nucleus

Cytoplasm

Cell membrane

Cytoplasm

Nucleus

Chloroplast

Vacuole

Cell wall

Flagellum

Chromosomes

Plasmid

Capsule

Cytoplasm

Animal Cell

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Cell Division

Also known as mitosis.
Cell division is a means of increasing the number of cells in an organism.

Single-celled organisms such as bacteria, rely on this to reproduce!

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Importance of Cell Division

Mitosis is essential for growth and repair.

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Keywords: mitosis / chromosome

Task 1:

In 2 to 3 sentences, explain why we need cells to divide?

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Importance of Cell Division

Cell division occurs in all living organisms and allows them to grow and repair damaged parts. In single-celled organisms, it allows them to reproduce.

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Learning Intention: To investigate how cells divide

Success Criteria

I can explain why it is important cells can divide

I can describe the process of mitosis.

I can discuss the importance of maintaining a chromosome complement.

I can state what happens if cell division is not controlled.

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Cell Structure

All cells contain genetic material - DNA. DNA is stored as chromosomes in the nucleus in animal, plant and fungal cells.

This genetic material needs to be copied for cell division to occur.

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Print this page for dagrams

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How do cells divide?

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Chromosomes are copied.

Nucleus disappears and chromosome pairs line up across the equator of the cell.

Chromosome pairs are pulled apart to opposite ends of the cell.

New nuclear membranes form and the cells splits to form two identical daughter cells.

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Optional Activity - Mitosis Flipbook

Make a flipbook showing the different stages of mitosis. There are several options depending on the level of difficulty.

Printing Here

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Learning Intention: To investigate how cells divide

Success Criteria

I can explain why it is important cells can divide

I can describe the process of mitosis.

I can discuss the importance of maintaining a chromosome complement.

I can state what happens if cell division is not controlled.

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Chromosome Complement

Chromosome complement is the number of chromosomes that a species of animal or plant possesses.

Each cell produced by cell division MUST have the same number of chromosomes as the cell it came from.

Pick 4 organisms and guess how many chromosomes they have?

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Eye-piece lens

Objective lens

Stage

Light source

Course Focus

Fine Focus

Arm

Base

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Microscope Activity

Collect a microscope and a slide and try to identify the different stages of mitosis.

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Remember, chromosomes carry genetic information (instructions to create and survive!)

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Why do chromosomes need to be copied so carefully?

During growth and development of an organism, the chromosomes will be able to provide the animal or plant with all the characteristics of its species.

Losing any chromosomes would mean a loss of genetic information – the information that allows the cell to function correctly!

This means that the cell will not function correctly or be able to carry out its job.

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Chromosome Complement.

New cells need to have the same chromosome complement as the original cell so they can carry out all of its functions.

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Down’s Syndrome

Gaining extra chromosomes can also be a problem!

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Learning Intention: To investigate how cells divide

Success Criteria

I can explain why it is important cells can divide

I can describe the process of mitosis.

I can discuss the importance of maintaining a chromosome complement.

I can state what happens if cell division is not controlled.

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Uncontrolled Cell Division

Cell division needs to be tightly controlled.

What do you think would happen if this control was lost?

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Cancer

Cancer develops when normal cell division does not stop and too many cells are made. These cells do not die like they are supposed to and can form a group called a tumour which grows into and damages cells around them.

Scientists believe that it could be changes in DNA that lead to cancers. Risk of cancer is increased with smoking, unhealthy diet, lack of exercise or overexposure to sun.

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Amazing Cell Division

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Cancer Cells

Find out the meaning of the following terms

Benign
Malignant
Metastasis

Research a type of cancer and find out the following:

What part of the body does this cancer affect?
What are the clinical symptoms?
How common is this cancer in the UK?
What is the treatment given for this cancer?
What research is being done on this cancer?
Is there a charity fundraising to help support people affected by this type of cancer?

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Cell Number

A cell divides every 20 minutes. How many cells would be produced from one original cell at the end of two hours?

10 cells divide every 60 minutes. How many cells will there be after 4 hours?

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The table below shows the number of cells in a bacterial colony over a period of time.

On a piece of graph paper, draw a line graph to show the number of cells against time.

(a) Calculate how many bacterial cells would be present in a culture if:

(b) A single bacterial cell divided every 30 minutes for 2 hours.

(c) A single bacterial cell divided every 20 minutes for 2 hours.

Time (hours)	Number of living cells present (hundreds)
0	2
2	4
4	16
6	60

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Learning Intention: To investigate how cells divide

Success Criteria

I can explain why it is important cells can divide

I can describe the process of mitosis.

I can discuss the importance of maintaining a chromosome complement.

I can state what happens if cell division is not controlled.