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
Protists
Diverse group that is usually single cells, but can form colonies. (Eukaryotic)
Fungi
Cell walls are made of chitin, and are heterotrophs, multicellular (Eukaryotic)
Plants
Are multicellular and have cell walls made of polysaccharides
- Large water filled vacuoles
- Autotrophs
(Eukaryotic)
Animals
Multicellular, do not have cell walls. They are heterotrophs (eukaryotic)
Archaea
Isoprenoid cell membrane, live in extreme environments (prokaryote)
Bacteria
Have a cell wall surrounding their cell membrane (prokaryotic)
Microfilaments
A double helix of actin monomers, part of the cytoskeleton
Intermediate filament
Only present in animals, a strong fibre composed of intermediate filament protein subunits, part of the cytoskeleton
Microtubule
A hollow tube formed from tubulin dimers, part of the cytoskeleton
