Module 1 (Introduction to Cell Biology and Cell Theory) Flashcards
Robert Hooke
In 1665, he first described chambers of cork as “cells”
What is a cell?
The fundamental, basic unit of life
Anton van Leeuwenhoek
In 1673-1700, he improved the magnifying power of microscope lenses, and saw “animalcules” in pond water
Light microscopy
Uses visible light and lenses to magnify images of small objects
Electron microscopy
Uses a beam of electrons to magnify the image. Since electrons are smaller, they are able to have a better resolution than traditional light.
Schleiden
In 1838, he was a German botanist that determined all plant tissues composed of cells, and plant embryos arise from single cells
Schwann
A German zoologist that determined that all animal tissues were made of cells in 1838, and that plants and animals are similar.
Virchow
A German zoologist that determined that cells can only arise from pre-existing cells in 1885
Cell Theory
- All living organisms are composed of one or more cells
- Each cell is the structural and functional unit of life
- Cells can only arise from pre-existing cells
Viruses
Small amounts of nucleic acids with a protein coat, requires a host cell to replicate
Viroids
A small circular RNA lacking a protein coat, and requires host machinery to replicate
Prions
Proteinaceous infectious particles, has no nucleic acids
Basic properties of cells
- Highly complex and organized but all are enclosed by a physical barrier
- Genetic program
- Capable of reproduction
- Acquire and utilize energy
- Carry out a variety of chemical reactions
- Engage in numerous mechanical activities
- Respond to stimuli
- Self-regulated
Prokaryote
“before nucleus”
- Has no membrane bound organelles, including a nucleus
- Most abundant organisms on Earth
Eukaryotes
“true nucleus”
- Contains a membrane bound nucleus
- Includes four domains
