Chapter 4: Microbial Growth - Influence of Nutritional factors Flashcards
1
Q
What are the nutritional factors that affect microbial growth? (4)
A
- Carbon
- N, S, P
- Trace elements
- energy
2
Q
How does carbon aid in microbial growth?
A
- required for all organic molecules
- backbone of living matter
3
Q
How is carbon used by heterotrophs and autotrophs?
A
- heterotrophs take carbon from organic matter (ex. sugars)
- autotrophs use inorganic carbon (ie. CO2)
4
Q
Why does N, S, P aid in microbial growth? (4)
A
- required in small amounts for the synthesis of cellular material
- ex. proteins, nucleic acids, phospholipids, ATP
5
Q
How do trace elements aid in microbial growth? (3)
A
- required in very small amounts
- iron, zinc, molybdenum
- essential to the function of certain enzymes
6
Q
How is energy essential to microbial growth?
A
- organisms need energy to build cell material and drive cellular processes
7
Q
What are two classifications of energy organisms?
A
- chemotrophs
- phototrophs
8
Q
What are chemotrophs? (2)
A
- organisms that acquire energy from chemical compounds
- may be organic or inorganic
ex. sugars
9
Q
What are phototrophs?
A
- harvest energy from sunlight
10
Q
What is nutritional diversitty?
A
- organisms are classified based on how they obtain their carbon and energy
- photoautotrophs, photoheterotrophs, chemoautotrophs, chemoheterotrophs
11
Q
What are photoautotrophs? (2)
A
- use sunlight for energy and CO2 as a carbon source (aka photosynthesis)
- includes some bacteria, algae, plants
12
Q
What are photoheterotrophs? (3)
A
- use sunlight for energy
- obtain organic carbon from food
- some bacteria (Heliobacterium spp)
13
Q
What are chemoautotrophs? (4)
A
- obtain energy from inorganic chemicals
- ex. H2, H2S
- use CO2 as a carbon source
- only done by some bacteria (sulfolobus and hydrogenovibrio)
14
Q
What are chemoheterotrophs? (4)
A
- Obtain energy from organic chemicals
- Use the same organic chemicals as their carbon source
- all animals, fungi, protozoa
- most bacteria
