Chapter 4: Culture, Growth, And Development Flashcards
Growth factors
Specific nutrients not required by all cells
Ions necessary for protein function
Mg, Ca, Fe, K
Uses preformed organic molecules
Heterotroph
Fix co2 and assembles into organic molecules
Autotrophs
Contains only compounds needed for an organism to grow
Defined minimal media
Obtain energy from redox
Chemotrophs
Use inorganic molecules as a source of electrons
Lithotrophs
2 types of heterotrophs
- Photoheterotrophs
2. Organotrophs
2 types of autotrophs
- Photoautotrophs
2. Lithotrophs
When chemical energy is used to pump protons out the cell, this forms a
Membrane potential
Posses nitrogenase, which converts n2 to ammonium ions
Nitrogen fixers
Oxidize ammonia to n2
Nitrifiers
Protist algae, such as single-celled euglena, are
Mixotrophic
The three ways of achieving selective permeability
- Substrate-specific carrier proteins (permeases)
- Nutrient-binding proteins in the
Periplasm - Protein channels or pores
Does facilitated diffusion require energy?
No
2 majn types of abc transporters
- Uptake (for nutrients)
2. Efflux (for antibiotics)
Specialized molecules secreted to bind ferric iron and transport it into the cell
Siderophores
Group translocation
A process that uses energy to chemically alter the substrate during its transport
An example of group translocation
The phosphotransferase system (pep) attaches phosphates to specific sugars as part of glycolysis
2 main types of culture media
- Liquid
2. Broth
Pure colonies are isolated via two main techniques
- Dilution streaking
2. Spread plates
Counting range for CFUs
25-250
Favor the growth of one organism over another
Selective media
Complex media to which blood components are added
Enriched media
