UTA Microbiology Exam 3 Questions With
Complete Solutions
Nutrients - .....ANSWER... ✔✔ acquired from the
environment and used for cellular activities
Essential Nutrient - .....ANSWER... ✔✔ any substance
that must be provided to an organism, they cannot
produce it themselves
What are some examples of essential nutrients? -
.....ANSWER... ✔✔ carbon, hydrogen, oxygen,
nitrogen, phosphorus, sulfur
Macronutrients - .....ANSWER... ✔✔ -required in
relatively large quantities
-play principal roles in cell structure and metabolism
Micronutrients - .....ANSWER... ✔✔ -present in smaller
amounts
-involved in enzyme function and maintenance of protein
structure
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Inorganic Nutrients - .....ANSWER... ✔✔ -simple
molecule that does not contain hydrogen and carbon
-metals and their salts
Organic Nutrients - .....ANSWER... ✔✔ -contain
carbon and hydrogen atoms, usually a product of living
things
-carbohydrates, proteins, vitamins, lipids, nucleic acids
Carbon Sources - .....ANSWER... ✔✔ heterotroph and
autotroph
heterotroph - .....ANSWER... ✔✔ -organism that must
obtain its carbon in organic form
-dependent on either life forms
-could eat: proteins, carbs, lipids, nucleic acids
autotroph - .....ANSWER... ✔✔ -organism that uses
inorganic CO2 as its carbon source
-makes its own "self feeder"
-not dependent on other living things
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Pseudomonas aeruginosa - .....ANSWER... ✔✔ -gram-
negative rod bacteria ubiquitous in the environ
-ability to use multiple carbon sources
-opportunistic pathogen
Nitrogen Sources - .....ANSWER... ✔✔ -Indispensable
to DNA, RNA, and ATP
- Nitrogen must be converted to NH3 before it enters
the cell
Oxygen Sources - .....ANSWER... ✔✔ -major
component of carbohydrates, lipids nucleic acids, and
proteins
-also found in inorganic compounds like inorganic salts
Hydrogen Sources - .....ANSWER... ✔✔ -found in
water, salts and naturally occurring gases
What is the role of hydrogen in cells? - .....ANSWER...
✔✔ 1. maintain pH
2. forms hydrogen bonds between molecules
3. serves as a source of free energy in oxidation-
reduction reactions of respiration
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Phosphorus Sources - .....ANSWER... ✔✔ -found in
rocks and oceanic mineral deposits
-main inorganic source is phosphate
-key component in nucleic acids and ATP
Sulfur Sources - .....ANSWER... ✔✔ -in rocks and
sediments in the environment
-essential in forming disulfide bridges that help
determine the shape and structural stability of protein
Growth factor - .....ANSWER... ✔✔ same thing as
essential nutrient
Phototroph - .....ANSWER... ✔✔ microbes that
photosynthesize
sunlight
-cyanobacterium
Chemotroph - .....ANSWER... ✔✔ microbes that gain
energy from chemical compounds
-E. Coli