Study Unit 2 Flashcards
Facultative organisms
Cells that can switch metabolic pathways to allow them to grow with or without oxygen.
Aerobic organisms
Cells that require oxygen for growth and metabolism.
Anaerobic organisms
Cells that are inhibited by oxygen.
Psychrophiles
Cells that can grow at low temp. (below 20 degrees Celsius).
Mesophiles
Cells that can grow in the temp. range of 20 to 50 degrees Celsius
Thermophiles
Cells that grow best at higher temp. (above 50 degrees Celsius)
Microbial diversity - Nutrient availability
Some organisms can grow in environments with almost no obvious source of nutrients (extremophiles).
Spherical cell’s name
coccus (plural - cocci)
Cylindrical cell’s (rod-shaped) name
bacillus (plural - bacilli)
Spiral-shaped cell’s name
spirillum (plural - spirilla)
Three main cell types
Eukaryotes
Prokaryotes (archaebacteria and eubacteria)
Viruses
Prokaryotic cells
Organisms without a cell nucleus or any other membrane bound organelles.
Eukaryotic cells
Organisms whose cells are organized into complex structures, internal membranes and a cytoskeleton.
Heat resistance of prokaryotes
High heat resistance
Heat resistance of eukaryotes
Low heat resistance
Viruses
Small infectious agents that can only replicate and survive in living cells
DNA
Deoxyribonucleic acid
All genetic information in free-living cells is contained on the DNA.
RNA
Ribonucleic acid
Bacteriophages
Virus that targets bacteria
Macronutrients
Carbon Nitrogen Oxygen Hydrogen Phosphorous Sulphur Potassium Magnesium
Cellulose
Cellulose is a polymer of beta-glucose
Comma shaped cell’s name
vibrio
Alkalophiles
Organisms that grow best with a pH of 9
Acidophiles
Organisms that grow best with a pH of 1 to 2
Neutrophiles
Organisms that grow best with a neutral pH
Yeast
A microscopic fungus capable of converting sugar into alcohol and carbon dioxide. Facultatively anaerobic
Fungi
Any of a group of spore-producing organisms feeding on organic matter, including moulds, yeast, mushrooms, and toadstools.
Mould
Tiny, multi-celled organisms made up of branching filaments (hyphae)
Algae
A diverse group of aquatic organisms that have the ability to conduct photosynthesis.
Protozoa
Unicellular organisms without cell walls
What do living cells consist of?
Amino acids
Proteins
Carbohydrates
Lipids, fats, steroids
Amino acids
Form the building blocks of proteins and enzymes
Which part of Escherichia Coli is the genus?
Escherichia
Which part of Escherichia Coli is the species?
Coli
5 main functions of proteins (types)
- Structural proteins
- Catalytic proteins
- Transport proteins
- Regulating proteins
- Protective proteins
Examples of structural proteins
- Glycoproteins
- Collagen (connective tissue)
- Keratin (hair and nails)
Examples of catalytic proteins
Enzymes
Examples of transport proteins
- Hemoglobin
* Serum albumin (carries of steroids, fatty acids and hormones)
Examples of regulating proteins
Hormones (insulin)
Examples of protective proteins
Antibodies bind to foreign macromolecules (antigens)
Role of carbohydrates
Cell’s main source of energy.
Types of carbohydrates
- Monosaccharides
- Disaccharides
- Polysaccharides
Monosaccharides
Monosaccharides (simple sugars) are the simplest form of sugar and the most basic units of carbohydrates. Their molecules contain 3 to 9 carbons.
Disaccharides
Disaccharides (double sugar) are the sugars formed when two monosaccharides are joined by condensation.
Polysaccharides
Polysaccharides are chain polymeric carbohydrates composed of monosaccharide units bound together by glycosidic linkages.
Condensation reaction between two amino acids
In a condensation reaction between two amino acids, a peptide bond is formed between the acid group of one amino acid and the amino group of another and a water molecule is released.
How do antibodies work?
Antibodies work by recognizing and sticking to specific proteins, such as those found on the surfaces of viruses and bacteria, in a highly specific way.
Formation of fats
Fats (triglycerides) are formed by the joining of three fatty acids and a glycerol backbone in a dehydration reaction. Three molecules of water are released in the process.
Where is the reaction between glycerol and fatty acids applied in biotechnology?
In the treatment of waste cooking oils for biodiesel production, the high acidity oils can be esterified with glycerol (a main byproduct of biodiesel production) to transform free fatty acids into triglycerides before performing transesterification.
Without performing this procedure before transesterification, the high acidity oils cannot be directly transformed into fatty acid methyl esters due to soap production.
Macronutrient: Carbon
Carbon is required to form carbohydrates, proteins, nucleic acids and many other compounds.
50% of the dry cell mass.
Macronutrient: Nitrogen
Nitrogen is part of proteins and nucleic acids and is also used in the synthesis of some vitamins.
10 - 14% of dry cell mass.
Macronutrient: Nitrogen - Sources
- Ammonia
- Ammonium salts
- Proteins
- Peptides
- Amino acids
- Fixation
- Urea
- Yeast extract
- Peptone
Macronutrient: Oxygen
Molecular oxygen is required as terminal electron acceptor in the aerobic metabolism of carbon compounds.
20% of dry cell mass.
Macronutrient: Hydrogen
Hydrogen, derived from carbohydrates, is used as energy source by methanogens.
8% of dry cell mass.
Macronutrient: Phosphorous
Phosphorous is necessary to synthesize nucleic acids and phospholipids.
3% of dry cell mass.
Macronutrient: Phosphorous - Sources
- Inorganic salts (K2HPO4 or KH2PO4)
* Glycerophosphates (organic source)
Macronutrient: Sulphur
Sulphur is part of certain amino acids and is present in several coenzymes. Sulphur also plays a role in photosynthesis as part of the electron transport chain.
1% of dry cell mass.
Macronutrient: Sulphur- Sources
- Sulphate salts (NH4)2SO4 most common
* Sulphur-containing amino acids
Macronutrient: Potassium
Required for carbohydrate metabolism and is a co-factor for certain enzymes.
Macronutrient: Potassium - Sources
• Potassium salts: K2HPO4, K2HPO4, K3PO
Macronutrient: Magnesium
Magnesium is present in the cell walls and cell membranes and is a co-factor for certain enzymes. Ribosomes require magnesium ions.
Macronutrient: Magnesium - Sources
• MgSO4.7H2O or MgCl2
Three classes of micronutrients
Generally required
Required under certain growth conditions
Rarely required
Generally required micronutrients and their role
Mn, Fe, Zn
• Important co-factors
• Regulates certain fermentations
• Regulates metabolic processes
DNA molecules in prokaryotes?
One
DNA molecules in eukaryotes?
More than one
DNA organelles & DNA observed as chromosomes in prokaryotes?
No
DNA organelles & DNA observed as chromosomes in eukaryotes?
Yes
Nuclear membrane in prokaryotes?
No
Nuclear membrane in eukaryotes?
Yes
Formation of partial diploid in prokaryotes?
Yes
Formation of partial diploid in eukaryotes?
No
Mitochondria in prokaryotes?
No
Mitochondria in eukaryotes?
Yes
Endoplasmic reticulum in prokaryotes?
No
Endoplasmic reticulum in eukaryotes?
Yes
Golgi apparatus in prokaryotes?
No
Golgi apparatus in eukaryotes?
Yes
Photosynthetic apparatus in prokaryotes?
Chlorosomes
Photosynthetic apparatus in eukaryotes?
Chloroplasts
Flagella in prokaryotes?
Single protein, simple structure
Flagella in eukaryotes?
Complex structure with microtubules
Spores in prokaryotes?
Endospores
Spores in eukaryotes?
Endo- and exospores
