Chapter 7: Bacterial Growth & Nutrition

02/07/25- Started flashcard set ~X

How is nutrition defined?

Defined as the process by which chemicals are acquired from the environments and used in cellular activities.

What are nutrients?

Materials that are used to construct new cellular components & required in large amounts.

How do macronutrients compare to micronutrients in terms of quantity and roles?

Macronutrients- Elements required in the greatest amounts and play a role in cell structure and metabolism

• C (carbon)

• H (hydrogen)

• O (oxygen)

• S (sulfur)

• P (phosphorus)

• N (nitrogen)

Micronutrients- Elements required for growth in small amounts for enzyme and pigment structures.

• Calcium

• Sodium

• Potassium

• Manganese

• Zinc

• Copper

What are the 2 types of nutrients?

Organic nutrients- contains carbon and hydrogen atoms and are usually the products of living thing.

• Methane (CH4)

• carbohydrates

• lipids

• proteins

• nucleic acids

Inorganic nutrients- atoms or molecules that contains a combination of atoms other than carbon and hydrogen.

• Metals and their salts (magnesium sulfate, ferric nitrate, sodium phosphate)

• gases (oxygen, carbon dioxide)

• water

What kind of nutrient is carbon dioxide considered? (CO₂)

Inorganic

What microbes are associated with carbon sources?

Autotrophs and Heterotrophs

What microbes are associated with energy sources?

Phototrophs and Chemotrophs

What do autotrophs (Most exclusively plants and algae) use for biosynthesis?

Inorganic carbon (CO₂)

What do heterotrophs use for biosynthesis?

Organic carbon

• CHO

• Lipids

• Proteins

• Nucleic acids, etc

Where do phototrophs get their energy?

They convert radiant energy into chemical energy. (mainly by storing solar as reduced carbon compounds). They use a process called photosynthesis.

Where do chemotrophs get their energy?

from Phototrophs. Specifically, they use preformed reduced carbon compounds formed by phototrophs.

Define Photoautotroph

Use sunlight & CO₂ or CO₃^-2

ex. Plants, algae, and many photosynthetic bacteria.

Define Photoheterotrophs

Use sunlight & organic compounds.

Ex. Few cyanobacteria and photosynthetic bacteria.

Define Chemoautotroph

Use inorganic compounds and BOTH energy and carbon sources.

Ex. Unique to very small number of bacterial species.

Energy sources include: H₂, Fe, S, NH⁴⁺, or NO^2-

Define Chemoheterotrophs

Use organic compounds as energy and carbon sources.

Ex. All protozoan, fungi, animals, and most bacteria (All pathogenic)

What are the 2 types of transport through membranes?

• Passive (no ATP exerted)

  • Diffusion

  • Facilitated diffusion

  • Osmosis

• Active (requires ATP)

Facilitated diffusion requires what to move molecules?

Channel proteins

What are the three types of osmotic solutions?

• Isotonic: Environment is equal in concentration to cell’s internal environment.

• HYPOtonic: solute concentration of external environment is lower than cell’s internal environment. Net movement of water INTO cell.

  • Most bacteria live in this condition.

• HYPERtonic: environment is greater in solute concentration than that of cytoplasm (internal environment of cell); movement OUT of cell.