Cells: How Can We See Them?

Vocabulary and key concepts from the lecture on cells and microscopy, including historical facts, types of microscopes, and slide preparation techniques.

Cells

The basic units of all life, also known as the building blocks of life.

Robert Hooke

The scientist who discovered cells in $1655$ at the age of $20$ years old.

Origins of Life

According to the transcript, the first cells appeared $35$ million years ago.

Microscopic

A term used to describe objects that can only be seen using a microscope.

Microscopy

The science of investigating small objects using microscopes.

Cytology

The study of cells.

Light Microscope

A type of microscope used in school laboratories that passes light through a thin specimen to create a 2D image with a magnification of $x1000$.

Monocular

A microscope that has one eyepiece or ocular lens.

Binocular

A microscope that has two eyepieces or ocular lenses.

Stereo Microscope

A microscope that reflects light off a specimen to create a 3D image with a magnification of $x100$, used to see the surface of small objects.

Electron Microscope

The most powerful type of microscope that uses beams of electrons instead of light, reaching a magnification of $x10,000,000$.

TEM

Transmission electron microscopes, where electrons pass through the specimen to allow visibility of the inside.

SEM

Scanning electron microscopes, where electrons reflect off the surface of the specimen to see the outside.

Total magnification formula

$$\text{Total magnification} = \text{ocular lens magnification} \times \text{objective lens magnification}$$

Coarse focussing knob

The part of a microscope used to move the stage and objective lens closer or further apart to bring the specimen into focus.

Fine focusing knob

The part of a microscope used to sharpen the focus on the specimen.

Wet mount

A slide preparation method involving placing a drop of water or stain onto a specimen and lowering a thin glass cover slip onto it.

Cover slip

A thin glass piece used to cover a specimen on a microscope slide during the preparation of a wet mount.