both microscope and cell theory

cell

basic structural unit of all life forms

cell theory 3 parts

cells are basic unit of life

cells arise from other preexisting cells

every living organism is made of cells

year of discovery

1655

cells discovered by

Robert hooke

first cell theory by who

scheiden and schwan in 1830s

transition electron microscope

most common best resolution magnify up to 15000000x

scanning electron microscope

good 3d imaging worse resolution than TEM

difference between electron and light microscopes

electron use electron beam and electromagnetic lenses

light microscopes use

light rays, 2 glass lenses

light microscope magnifies

up to 2000x

electron microscope magnifies

up to 2000000x

usefulness of microscopes in regards to cell structure

enabling scientists to visualize and study cells, which are too small to be seen with the naked eye

Light Microscope

Uses visible light for illumination.

Electron Microscope

Uses a beam of electrons for illumination.

Magnification of Light Microscope

Up to ~1,000x.

Magnification of Electron Microscope

Up to ~2,000,000x.

Resolution of Light Microscope

~0.25-0.3 µm.

Resolution of Electron Microscope

~0.001 µm.

Specimen Type for Light Microscope

Can observe live or dead specimens.

Specimen Type for Electron Microscope

Can only observe dead or dried specimens.

Image Output of Light Microscope

Produces colored images.

Image Output of Electron Microscope

Produces black and white images (can be colorized digitally).

Lens Material of Light Microscope

Made of glass.

Lens Material of Electron Microscope

Uses electromagnetic lenses.

View Format of Light Microscope

2D (some stereo microscopes offer 3D).

View Format of Electron Microscope

2D or 3D depending on type (TEM or SEM).

Preparation Time for Light Microscope

Minutes to hours.

Preparation Time for Electron Microscope

Several days.

Portability of Light Microscope

Compact and movable.

Portability of Electron Microscope

Large, stationary equipment.

Cost of Light Microscope

Affordable for schools and hobbyists.

Cost of Electron Microscope

Expensive; used in advanced labs.

Applications of Light Microscope

Used in education, basic biology, and live cell study.

Applications of Electron Microscope

Used in nanotech, virology, and materials science.

Field of View (FOV)

The diameter of the visible area under the microscope.

Relationship between Magnification and FOV

As magnification increases, the field of view decreases.

Cell Theory - First Tenet

All living organisms are composed of one or more cells.

Cell Theory - Second Tenet

The cell is the basic unit of structure and function in living things.

Cell Theory - Third Tenet

All cells arise from pre-existing cells.

Robert Hooke

Coined the term 'cell' after observing cork under a microscope.

Matthias Schleiden

Proposed that all plants are made of cells.

Theodor Schwann

Concluded that all living things are composed of cells.

Rudolf Virchow

Added the tenet that all cells arise from pre-existing cells.

Conversion of Millimetre to Micrometre

1 mm = 1000 µm.

Example of Conversion

15 mm = 15 × 1000 µm = 15000 µm.