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Prokaryotic Cells

It's a single-celled organism... Bacteria are an example of prokaryotes. Prokaryotic cells do not contain a nucleus or any other membrane-bound organelle. Prokaryotes include two groups: bacteria and another group called archaea.


Eukaryotic cells

Your cells are eukaryotic. Eukaryotic cells contain membrane-bound organelles, including a nucleus. Eukaryotes can be single-celled or multi-celled, such as you, me, plants, fungi, and insects.


What is the role of the ribosome?

Where proteins are made in the cell


What happens in the nucleus?

contains genetic material that controls the activities of the cell.


What happens in the cytoplasm?

Gel-like substance where chemical reactions happen.


Name and describe the structure of an animal cell


What is the cell wall made up of, and what does it do?

Cellulose: strong


Where does photosynthesis occur?



What does a permanent vacuole contain?

Cell sap


Name and describe the structure of a plant cell...


Bacterial Cell

(include: what type of cell it is, etc)

  • Prokaryotic cell
  • Don't have a nucleus
    • Single cellular strand of DNA float freely in cytoplasm


Magnification = ... 

size of image ÷ size of real object


What is a nanometre in standard form?

1 x 10-9


What does resolving power mean?

A measure of the ability to distinguish between two separate points that are very close together.


What is the difference between a light microscope and an Electron Microscope?

Electron Microscope:

  1. x 2,000,000
  2. Invented in the 1930s
  3. Can see the subcellular structures inside cells
  4. Use a beam of electrons to form an image
  5. resolving power - 200nm
  6. Very large, expensive and have to be kept in special temperature, pressure and humidity

Light Microscope:

  1. x 2000
  2. Invented in the mid-17th Century 
  3. To look at cells
  4. It uses beams of light to form an image of an object
  5. resolving power - 0.2nm
  6. See image below


Label an animal cell... Give definitions...

  • Nucleus - controls all the activities of the cell and is surrounded by the nuclear membrane. Contains the genes on the chromosomes that carry the instructions for making the proteins needed to build new cells or new organisms. 
  • Cytoplasm - A liquid gel in which the organelles are suspended and where most of the chemical reactions needed for life take place
  • Cell Membrane - Controls the passage of substances such as glucose and mineral ions into the cell. It also controls the movement of substances such as urea.
  • Mitochondria - Structures in the cytoplasm where aerobic respiration takes place, releasing energy for the cell.
  • Ribosomes - Where protein synthesis takes place, making all the proteins needed in the cell


Label a Plant cell... Give definitions...

  • Cell Wall - the rigid structure around the contents of a cell that controls what moves in and out of the cell
  • Cellulose - The complex carbohydrate that makes up plant and algal cell walls and gives them strength
  • Chloroplasts - The organelles in which photosynthesis takes place
  • Chlorophyll - The green pigment contained in the chloroplasts
  • Permanent vacuole - Space in the cytoplasm filled with cell sap


What is the difference between an animal cell and plant cell?

Plant cells make their food by photosynthesis, they don't move their bodies about from one place to another and they are a lot bigger,


Required practical: Looking at cells


Eukaryotic cells

Cells from eukaryotes that have a cell membrane, cytoplasm and genetic material enclosed in the nucleus


Example of a eukaryotic cell

animal and plant cells


What is genetic material?

is a chemical called DNA and this forms structures called chromosomes that are contained within the nucleus


Prokaryotic cells 

(Include: definition what the cell looks like)

From Prokaryotic organisms have a cytoplasm surrounded by a cell wall that does not contain cellulose. The Genetic material is a DNA loop that is free in the cytoplasm and not enclosed by a nucleus. Sometimes there are one or more smaller rings of DNA called plasmids.


Example of a prokaryotic cell

Bacteria... Single-celled living organisms


Can Bacteria be Harmful?

Yes... They can cause diseases in humans and other animals and also plants. They can also decompose and destroy stored food.


Relative sizes examples


What happens as an organism develops?

The cells differentiate to form different types of cells


What happens as an animal cell differentiates to form a specialised cell?

It acquires different sub-cellular structures to enable it to carry out a certain function.


Name examples of specialised cells...

Nerve cells, muscle cells and sperm cells


Nerve Cell Diagram

Specialised to carry electrical impulses around the body of an animal. Provide rapid communication system between the different parts of the body which have several adaptations including:

  • Lots of dendrites to make connections to other nerve cells
  • Axon carrying the nerve impulses from one place to another
  • Synapses are adapted to pass the impulses to another cell/between a nerve cell and muscle cell