Lesson 6.2: Classifying Bacteria and Reproduction Flashcards
Review: prokaryotic and eukaryotic, what are they?
prokaryotic: cell that does not have its chromosomes surrounded by nuclear envelope and lacks membrane bound organelles Ex: bacteria
eukaryotic: cell that has a nucleus surrounded by a nuclear envelope and has membrane bound organelles Ex: plant, animal, protists, fungi
All bacteria are..
- unicellular
- are prokaryotic
- have a single chromosome in the form of a loop of DNA called a plasmid
- most reproduce asexually by binary fission, some reproduce sexually by conjugation
- thrive in moist environments
How to classify bacteria
- if they cause disease
- gram positive or gram negative
- shape
- configuration
- oxygen requirements
- nutrition
If bacteria can cause disease, they are classified by 2 ways….
- pathogenic
- non pathogenic
Gram positive
- stains purple
- cell wall contains peptidoglycan (protein)
ex: staphylococcus
Gram negative
- stains pink
- cell wall does not contain peptidoglycan (protein)
ex: E. coli
Classifying bacteria by shape
- spherical
- rod-shaped
- spiral
can also be seen in..
- clumps (staphyllo)
- chains (strepto)
- pairs (diplo)
Classifying bacteria by configuration
- after division, many bacteria stay together in groups called colonies
- colonies are visible growths of microorganisms that contain millions of cells
- in colonies, bacterial cells stay together in typical arrangements
Classifying bacteria by oxygen requirements
- aerobes (needs lots of O2) Ex: TB
- anaerobes (cannot survive in the presence of O2)
Ex: botulism
Classifying bacteria by nutrition
can be autotrophic, heterotrophic, photosynthetic, or chemosynthetic
Review: 2 types of reproduction
- Asexual reproduction (binary fission)
- Sexual reproduction (conjugation)
