1
Bio100 Lecture 3-4
What is a cell?
Cell Theory
Common Features of the Cell
Prokaryotes Pro=before, karyote=nucleus
Bacteria – Kingdom Monera
Two Groups of Bacteria –
 Arcaea – live in extreme environments – ex. Hot springs
o Chemotrophs – chemosyntheic – get energy from chemical such
as methane or hydrogen gas
2
Bio100 Lecture 3-4
o Extreme halophiles thrive in very salty places.
o Extreme thermophiles thrive in very hot water, such as geysers,
and acid pools.
 Eubacteria o What we consider more common – bacteria in our normal world
Shape of Bacteria - .
 Cocci
 Bacilli
 Spiral
Short and rigid prokaryotes are called spirilla.
Longer, more flexible cells are called spirochetes.
The Role of Bacteria
Two sources of carbon are used by prokaryotes.
o Autotrophs
o Heterotrophs
3
Bio100 Lecture 3-4
Cyanobacteria – a type of bacteria
Eukaryotes
Eu=true, karyote=nucleus
 Kindoms:
o Protistia
o Fungi
o Plantae
o Animalia
Protista
 autotrophs
 heterotrophs
Locomotion
 Cillia
 Flagella
 Pseudopods
4
Bio100 Lecture 3-4
The Cell
Basic Parts of the Cell
 Cell/Plasma membrane
 Nucleus –
 Ribosomes –
 Endoplasmic Reticulum (ER)
o Smooth ER
o Rough ER
5
Bio100 Lecture 3-4
 Golgi apparatus
 Lysosome
 Vacuoles
 Many of these organelles interact in the
o synthesis,
o distribution,
o storage, and
o export of molecules.
**What do these molecules do?**
Mitochondria
The mitochondrial matrix contains:
Chloroplasts
6
Bio100 Lecture 3-4
Mitochondria and chloroplasts contain
• DNA and
• ribosomes.
The endosymbiont theory states that
• mitochondria and chloroplasts were formerly small prokaryotes and
• they began living within larger cells.
Cellular Support
A plant cell, but not an animal cell, has a rigid cell wall that
• protects and provides skeletal support that helps keep the plant
upright and
• is primarily composed of cellulose.
Animal Cells have cell/plasma membrane
Review
• Eukaryotic cell structures can be grouped on the basis of four functions:
1. genetic control,
2. manufacturing, distribution, and breakdown of materials,
3. energy processing, and
4. structural support, movement, and intercellular communication.
7
Bio100 Lecture 3-4
Central Vacuole
1.
2.
3.
4.
5.
6.
7.
8.
What is a cell?
Define Prokaryote?
What two domains are prokaryotes?
Why are prokaryotes so important?
What is an organelle?
Where is DNA stored in a eukaryotic cell?
Understand the roles of the different organelles.
What is the difference between a plant and animal cell?