MICROBIAL NUTRITION OUTLINE

Nutrition

The process by which chemical substances (nutrients) are acquired from the environment and used in cellular activities.

Essential Nutrients

Elements or molecules that must be provided to an organism because they cannot be synthesized by the organism.

Growth Factors

Essential organic nutrients that must be provided as an organism cannot make them on its own, such as essential amino acids and vitamins.

Macronutrients

Nutrients required in large quantities, such as proteins and carbohydrates.

Micronutrients

Also known as trace elements, these are required in small amounts for protein structure and enzyme function.

Organic Nutrients

Nutrients that contain carbon and hydrogen atoms.

Inorganic Nutrients

Nutrients that do not contain carbon and hydrogen, including metals and their salts.

Heterotroph

An organism that must obtain carbon in an organic form made by other living organisms.

Autotroph

An organism that uses CO2, an inorganic gas as its carbon source, not dependent on other living things.

Chemotroph

An organism that gains energy from chemical compounds.

Phototroph

An organism that gains energy through photosynthesis.

Active Transport

Transport that requires energy to move substances against the concentration gradient.

Passive Transport

Transport that does not require energy, moving substances down their concentration gradient.

Facilitated Diffusion

Passive transport that requires a carrier protein to help move substances across the membrane.

Hypertonic solution

A solution with more solute compared to another solution.

Hypotonic solution

A solution with less solute compared to another solution.

Isotonic solution

A solution with equal solute concentration compared to another solution.

Psychrophiles

Organisms that thrive at optimum temperatures below 15 °C.

Mesophiles

Organisms that thrive at moderate temperatures between 20 °C and 45 °C.

Thermophiles

Organisms that thrive at temperatures above 45 °C.

Aerobe

An organism that utilizes oxygen and can detoxify it.

Anaerobe

An organism that does not utilize oxygen for growth.

Facultative Anaerobe

An organism that can grow with or without oxygen but prefers oxygen.

Neutrophiles

Microorganisms that grow at a pH between 6 and 8.

Halophiles

Organisms that require high concentrations of salt to survive.

Symbiotic Relationship

Close nutritional relationships where organisms are dependent on one another.

Mutualism

A type of symbiotic relationship where both organisms benefit.

Commensalism

A type of symbiotic relationship where one organism benefits and the other is not harmed.

Parasitism

A relationship where the parasite benefits at the expense of the host.

Synergism

When two or more organisms work together to produce a combined effect greater than the sum of their individual effects.

Microbial Growth

Growth that occurs at the cellular level through processes like binary fission and at the population level through increase in biomass.

Binary Fission

The process by which a parent bacterial cell divides to form two daughter cells.