Castlehead High School

Intermediate 2

Introduction to Cells

J Offord

Castlehead High School

Animal cells have three basic parts.

Nucleus

Cytoplasm Cell membrane

An animal cell

NUCLEUS - controls the cell and contains genetic information.

CYTOPLASM – where chemical reactions happen

CELL MEMBRANE – controls what enters and leaves the cell and gives the cell shape.

Animal Cells

Castlehead High School

Plant CellsThe plant cell has some parts the same as an animal cell…

Nucleus

Cytoplasm

Cell membrane

VacuoleContains cell sap - helps with support

ChloroplastContains chlorophyll - absorbs sunlight for photosynthesis

Cell wallMade of cellulose and supports cell

..and some different to an animal cell.

Castlehead High School

Yeast

• Yeast is a type of plant called a fungus• Yeast can be used to make • BREAD• WINE• BEER• GASOHOL – a fuel used to drive cars

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Fermentation

• Yeast breaks down glucose to make carbon dioxide gas and alcohol (or ethanol)

• This process is called fermentation• The word equation for this reaction is

Glucose Carbon Dioxide

and Alcohol

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Bacteria

• Bacteria can be used to make yoghurt

• The bacteria feed on LACTOSE sugar in the milk turning it into LACTIC ACID

• This drop in pH makes the proteins in milk clump together

• Word Equation:Lactose Lactic acid

(broken down by bacteria)

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Fungi

• First antibiotic discovered by Alexander Flemming

• Called penicillin – came from a fungus

• Antibiotic is a chemical that prevents bacteria growing

• Only effective against bacteria not against viruses

Castlehead High School

More to do

1. Click on the link below and go to the website my skoool http://kent.skoool.co.uk/keystage3.aspx?id=63

and look over the lessons

2. Cell Structure and Function and Plant Cells

3. Then go to bitesize revision http://www.bbc.co.uk/scotland/education/bitesize/standard/biology/investigating_cells/index.shtml read over the cells topic and answer the questions