- Briefly describe the three components of the cell theory.
- All living things are made of cells
- Cells are the basic unit of structure and function in an organism (basic unit of life)
- Cells come from the reproduction of existing cells (cell division)
- How can you distinguish a prokaryote from a eukaryote?
- No nucleus
- No membrane bound organelles
- Smaller & less ribosomes
- Most are smaller than eukaryotes
- Most are single-celled organisms
- Describe the differences between the two kingdoms Archaebacteria and Eubacteria.
- Domain - Archae
- Kingdom-Archaebacteria:
- Harsh environments
- Cell structures differ from other bacteria
- Domain – Bacteria
- Kingdom-Eubacteria:
- traditional bacteria
- Peptidoglycan in cell wall (protein)
- habitats: land, internal, water
- Identify the four main groups of archaebacteria and the habitats they can be found in.
- Methanogens
- Produce methane
- Live in swamps, guts of cows & humans
- Used to treat sewage & purify water
- Thermoacidophiles
• Live in hot acidic H 2 0
- Chemosynthesizers
- Live in deep sea volcanic vents
- Use inorganic compounds for energy (H 2 S)
- Halophiles
Live in extremely salty places (eg. Dead Sea or Salt Lake)
- Describe the three main groups of eubacteria, and the characteristics that distinguish them
from each other. (KEY POINTS ONLY – VERY BRIEFLY)
- Gram Positive Bacteria
- Cell wall made of protein and sugar
- Thick layer of peptidoglycan
- Turn purple after gram staining
- Gram Negative Bacteria
- Extra layer of lipid outside of cell wall
- Thin layer of peptidoglycan
- Turn pink/red after gram staining
- Require different types of antibiotics to treat infections
- Cyanobacteria
• Perform plant-like photosynthesis
O 2 is released as bi-product
- Bacteria are extremely diverse? What six characteristics are used to identify and describe
bacteria.
i. Cell Shape (go over the basic shapes)
ii. Cell Wall (identify the difference between gram negative and
positive)
iii. Motility
iv. Colony Appearance
v. Method of Nutrition
vi. Cellular Respiration
- Describe how bacteria reproduce
(a) Sexually
Conjugation (sexual reproduction)
• DNA is exchanged between bacteria cells
• Cell to cell contact using pili
• Increases diversity
Transformation (sexual)
• Bacteria cells that pick up DNA from dead bacteria cells
Transduction (sexual)
Use of viruses to transfer DNA between bacteria cells
(b) Asexually Binary Fission (asexual reproduction)
• Method of reproduction for most bacteria • Occurs under normal conditions • Process: 1. DNA replicates (ie. doubles) 2. Cell divides 3. Result: 2 identical daughter cells
- Explain the differences between obligate aerobes, obligate anaerobes, and facultative
anaerobes.
Cellular Respiration is the process by which nutrients are broken down to provide energy
A. Obligate aerobes
• Need oxygen to live (eg. Tuberculosis)
B. Obligate anaerobes
• Killed by oxygen (eg. Clostridium tetani in deep wounds)
C. Facultative anaerobes
• Can use oxygen if it is available (eg. E. coli in human intestines)
