The cell theory and the microscopes 4º ESO IES Pedro de Luna -ZARAGOZA

The cell theory and the microscopes

By: Marina Járboles, Cristina Alierta and Pilar Ballesteros.

The cell theory

The cell theory

• Formulated by:

• Other scientists that contributed:

The cell theory

• It states that:• 1)  All living things are made up of cells.

• 2) Cells are the basic structural and functional unit of life.

• A good example will be this dog:

• 3) Cells come from pre-existing cells by division.

New statements:

• 4) Energy flow occurs within cells.

Reaction of cellular respiration

• 5) Hereditary information (DNA) is passed on from cell to cell.

• Eukaryotic cells division

• Prokaryotic cells division:

• 6) All cells have the same basic chemical composition.

Activity • Say which of this statements belong to the

original theory and which ones are new:

• Cells come from pre-existing cells by division.• All cells have the same basic chemical

composition.• Hereditary information (DNA) is passed on from

cell to cell.• All living things are made up of cells.• Cells are the basic structural and functional unit

of life.• Energy flow occurs within cells.

Answer• Original theory:• Cells come from pre-existing cells by division.• All living things are made up of cells.• Cells are the basic structural and functional unit of life.

• New statements:• Energy flow occurs within cells.• All cells have the same basic chemical composition.• Hereditary information (DNA) is passed on from cell to

cell.

Important scientists in cell theory• 1) Robert Hooke• 2) Antony Van Leeuwenhoek• 3) Robert Brown• 4) Mattias Schleiden• 5) Theodor Schwann• 6) Rudolph Virchow

1. Robert Hooke• 1635-1703

• In 1665 he published “Micrographia”

•The first to identify and name a cell

2. Antony Van Leeuwenhoek• 1632-1723• Made better lenses

Red blood cells as he saw themWhite blood cell

•The first to observe a living cell

Bacteria in his saliva Dog sperm Human sperm

3. Robert Brown• 1773-1857• He discovered the nucleus of cells

4. Mattias Schleiden• 1804-1881• First to note that all plants were made up

of cells

5. Theodor Schwann• 1810-1882• Concluded that all living things were made

up of cells

6. Rudolph Virchow• 1821- 1902• Proposed that cells come from other cells

Cell theory• 1. All living things are made up of cells.• 2. Cells are the basic structural and

functional unit of life.• 3. Cells come from pre-existing cells by

division.

• This is how an eukaryotic animal cell would look like:

Activity• Say the name of the scientists who

contributed with the cell theory in order

Answer• 1. Hooke• 2. Van Leeuwenhoek• 3. Brown• 4. Schleiden• 5. Schwann• 6. Virchow

Major contibutions to the cell theory

• Say how do you think each scientist contributed to the creation of the cell theory:

• Hooke• Van Leeuwenhoek• Brown• Schleiden• Schwann• Virchow

Major contibutions to the cell theory

• Hooke: The first to identify and name a cell• Van Leeuwenhoek: Made better lenses and was

the first to observe a living cell• Brown: He discovered the nucleus of cells• Schleiden: First to note that all plants were made

up of cells• Schwann: Concluded that all living things were

made up of cells• Virchow: Proposed that cells come from other

cells

The microscopes

Definition

History of microscopes

• 1st century AD• Magnifiers

• 1590’s• Zacharias Janssen and his father Hans

• Antony Van Leeuwenhoek

• Hooke

True or false• Hooke was the first man to make a real

microscope• Hooke was the first man to use a three-

lens configuration in a microscope• There are still some Jansen’s microscopes• Romans invented microscopes

• Hooke was the first man to make a real microscope: False

• Hooke was the first man to use a three-lens configuration in a microscope: True

• There are still some Jansen’s microscopes: False

• Romans invented microscopes: False

Types of microscopes

1. Optical microscopes• 1.1 Compound microscope• 1.2 Stereo microscope• 1.3 Confocal microscope

1.1 Compound microscope

Fresh water shrimp, Gammarus

1.2 Stereo microscope

Cell division in a frog’s egg

1.3 Confocal microscope

Aquatic worm

Activity• Join the microscope name with its picture

Confocal microscope

Stereo microscope

Compound microscope

Answer

Confocal microscope

Stereo microscope

Compound microscope

2. Electron microscopes2.1 Transmission Microscope

2.2 Scanning Electron Microscope

2.3 Reflection Electron Microscope

2.1 Transmission electron Microscope

Lung tissue

2.2 Scanning Electron Microscope

Pollen

Activity• Join the microscope name and the image

you can see through it

Scanning electron microscope

Transmission electron microscope

Answer

Scanning electron microscope

Transmission electron microscope

2.3 Reflection Electron Microscope

• 2.3.1 X-ray Microscope • 2.3.2 Scanning Helium Ion Microscope• 2.3.3 Scanning acoustic microscope • 2.3.4 Scanning Probe Microscopes

2.3.1 X-ray Microscope

Bacteria

2.3.2 Scanning Helium Ion Microscope

2.3.3 Scanning acoustic microscope

Lymph node

2.3.4 Scanning Probe Microscopes

Purple membrane

Activity• Join the microscope name with its picture

• X-ray Microscope

• Scanning Helium Ion Microscope

• Scanning acoustic microscope

• Scanning Probe Microscopes

Answer• Join the microscope name with its picture

• X-ray Microscope

• Scanning Helium Ion Microscope

• Scanning acoustic microscope

• Scanning Probe Microscopes

• Now lets see if you can solve this crossword:

• Finally lets see if you remember some of the microscope parts:

The end