14.1 Cell Theory & Microscopes

Front

Cell Theory

Back

A fundamental concept in biology stating that all living organisms are made of cells, cells are the basic units of life, and all cells come from pre-existing cells.

Front

Eukaryotic Cell

Back

A cell that has a true nucleus enclosed by a membrane and other membrane-bound organelles like mitochondria and the Golgi apparatus.

Front

Prokaryotic Cell

Back

A simple, single-celled organism that lacks a nucleus and membrane-bound organelles. Includes kingdoms bacteria and archaea.

Front

Cell Membrane

Back

A flexible, semi-permeable barrier made of a lipid bilayer that surrounds the cell, controlling what enters and exits while maintaining homeostasis.

Front

Nucleus

Back

The control center of a eukaryotic cell that contains DNA and regulates cell activities like growth, metabolism, and reproduction.

Front

Light Compound Microscope

Back

A microscope that uses visible light and multiple lenses to magnify thin specimens up to about 1000x. Ideal for viewing cells and tissues.

Front

Scanning Electron Microscope (SEM)

Back

A microscope that uses a beam of electrons to scan the surface of a specimen up to about 1,000,000x, producing detailed 3D images of its texture and structure.

Front

Transmission Electron Microscope (TEM)

Back

A high-resolution microscope that sends electrons through a thin specimen to reveal internal structures like organelles and viruses up to 50,000,000x.

Front

Micrometers

Back

Metric unit of length equal to one millionth of a meter (1 µm = 0.000001 m). Commonly used in science to measure extremely small things like cells, cell membrane thickness, and bacteria.

Front

Scientific Theory

Back

A well-tested explanation for a wide range of observations or experimental results, supported by evidence.