Chapter 7 - McGraw Hill Microbiology

Nutrients

Substances acquired from the environment and used in cellular activities such as metabolism and growth.

Essential Nutrients

Any substance, weather in elemental or molecular form, that must be provided to an organism

Macronutrients

Substances that are required in relatively large quantities such as Carbon, Hydrogen and oxygen.

Micronutrients

Substances required in very small quantities, such as manganese, zinc and nickel.
aka- trace elements

Trace Elements

Micronutrients required for cellular processes. Involved in enzyme function and maintenance of protein structures.

Heterotroph

An organism that uses carbon from an organic form.

Autotroph

An organism that uses inorganic CO2 as its carbon source. It can fix carbon to create organic compounds

Growth Factor

An organic compound that cannnot be synthesized by the organism, which must be provided as a nutrient.

Phototroph

An organism that synthesizes energy from light

Chemotroph

An organism that synthesizes energy from other organic or inorganic materials.

Photoautotroph

An organism that synthesizes energy from light and fixes carbon from CO2
Ex Photosynthetic organisms (Algea, plants, cyanobacteria)

Chemoautotroph

An organism that synthesizes energy from organic or inorganic materials and fixes carbon from CO2

Chemoorgoautotroph

An organism that synthesizes energy from only organic materials and fixes carbon from CO2
Ex: Mathanogens

Lithoautotroph

An organism that synthesizes energy from inorganic carbon and fixes carbon from CO2

Methanogen

An organism that derives energy from organic compounds and fixes carbon from CO2. Created methane gas

Chemoheterotroph

An organism that derives energy and receives carbon through the conversion of nutrients from other organisms
Ex: Protozoa, fungi, many bacteria, animals

Aerobic Respiration

Cellular metabolic processes that take place in the presence of elemental oxygen

Saprobe

An organism that derives energy and receives carbon through the conversion of nutrients from DEAD organisms.
Ex: Fungi, Bacteria

Parasite

An organism that derives energy and receives carbon through the conversion of nutrients from a LIVE host organism.
Ex: Bacteria, fingi, protozoa, animals

Pathogen

an organism that causes disease

troph-

Root work meaning Food
ex: Trophozite

-phile

Root work meaning to Love
ex: extremeophile

-obe

Root word meaning to Live
Ex: microbe (live small)

hetero-

Root word meaning other
Ex: Heterotroph (requires other organisms)

auto-

root word meaning self
Ex: Autotroph (creates it's own energy)

sapro-

root word meaning rotton
Ex: Saparobe (lives on dead organic matter)

halo-

root word meaning salt
Ex: Halophile

thermo-

root word meaning heat
Ex: thermophile

psychro-

root word meaning cold
Ex: Psychrophile

Aero-

root word meaning air (oxygen)
Ex: Aerobe

Diffusion

atoms or molecules moving in a gradient from an area of higher concentration to lower concentration. Utilizes a fundamental property of random motion.

Osmosis

Diffusion of water through a selectively permeable membrane

Isotonic

A solution that matches the concetration of water inside and outside the cell are equal. The rate of diffusion is equal into and out of the cell.

Hypotonic

A solution where the extracellular water concentration is higher than inside the cell. The net diffusion is into the cell.

Hypertonic

A solution where the extracellular water concentration is lower than inside the cell. The net diffusion is out of the cell.

Facilitated Diffusion

Utilizes membrane transport proteins that allow for the diffusion of molecules into and out of the cell.

Protein/Enzyme Specificity

Proteins and Enzyme Active Sites that will interact with specifically shaped molecules.
These could be Substrate or inhibitors

Transport Protein Saturation

The maximum rate a carrier protein can transport an atom or molecule.

Transport Protein Binding Competition

When multiple molecules can bind to a specific carrier protein. Either the molecule with a higher bonding affinity or concentration will be transported at a greater rate.

Active Transport

Energy-requiring process that moves material across a cell membrane against a concentration difference

Group Translocation

Merges the transport and conversion of a substance (nutrient) so that it is immediately useful inside the cell.

Endocytosis

The process where large molecules, particles, liquids or even other cells are enclosed by the cell membrane forming a vacuole.

Phagocytosis

A type of endocytosis in which a cell engulfs large particles or whole cells

Pinocytosis

A type of endocytosis in which the cell ingests extracellular fluids like oils or solutions.

Maximum Temperature

highest temperature that permits a microbe's growth and metabolism

Minimum Temperature

lowest temperature that permits a microbe's growth and metabolism

Optimum Temperature

The templerature that permits a microbes optimal growth and metabolism.

Mesophile

an organism that grows best in moderate temperature, neither too hot nor too cold, with an optimum growth range from 20 to 45 °C

Psychrophile

An organism that grows best at about 15°C and does not grow above 20°C; a cold-loving microbe.

Thermophile

An organism that grows best above 45C with a growth range of 45 to 80.

Hyperthermophile

An organism that thrives in extremely hit environments - from 60C upwards.

Aerobe

An organism that uses elemental ozygen in metabolism and has the ability to detoxify it's bi-products

Anaerobe

A microbe that lacks the metabolic enzyme systems for using elemental oxygen in metabolism.

Obligate Aerobe

An organism that requires elemental oxygen for metabolism.

Obligate Anaerobe

An organism that cannot grow in the presence of elemental oxygen

Facultative Anaerobe

A microbe that does not require oxygen for it's metabolism and is cabable of growth in the absence of it.

Microaerophile

A microbe that does not grow at normal atmospheric concentrations of oxygen, but requires a small amount for metabolism.

Aerotolerant Anaerobes

Microbes that do not utiliae oxygen but can survive and grow to a limited extent in it's presence.

Acidophile

An organism that lives (grows and replicates) best at low pH (acidic) environments

Alkalinophile

An organism that lives (grows and replicates) best at high pH (basic) environments

osmophile

Organisms that lives (grows and replicates) best in habitats of high solute concentration

Halophile

Organisms that live (grow and replicates) in high concentrations of salt.

Barophile

Organisms that live (grow and replicates) in high hydrostatic pressure

Mutualism

A symbiotic relationship where both organisms benefit

Commensalism

A symbiotic relationship between two organisms in which one organism benefits and the other is unaffected

Parasitism

A symbiotic (close living) relationship in which one organism benefits at the expense of the other

Antagonism

A non-symbiotic (free living) relationship where some organisms inhibit or destroy other organisms.

Synergism

A non-symbiotic (free living) relationship where some organisms cooperate and share nutrients

Symbiotic Associations

Multiple organisms living closely where at least one of the organisms requires the relationship to survive.

Biofilm

A group of microorganisms that adhere to the surface and create a polymeric substance that covers the cells. One or many cells can be part of a biofilm, where characteristics or the cells can change from when they are free living.

Quorum Sensing

The ability of bacteria to sense the presence of other bacteria via secreted chemical signals. The chemical signals can adjust bacterial functions.

Binary fission

A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size

Generation Time

The time it takes for a specific cell to divide into 2 cells.
Also known as Dividing Time

Exponential Growth

Growth pattern in which the individuals in a population reproduce at a constant rate. In bacteria each cell doubles

Growth Curve

graph of the number of organisms in growing population over time.
Divided into: Lag, log, stationary and death phases

Turbidity

A measure of how much light can pass through a solution.
Can be used to measure the density of cell in a solution.

Direct Cell Counts

Total number of cells (living and dead)
Counting can be done by:
Cytometer (a specific microscopic slide)
Coulter counter (a electronic scanning counter)