BIOL 3200 Final Exam 2 (Dr. Mehari -
Auburn) Questions with Guaranteed
Pass Solutions 2025-2026 Updated.
Macronutrients - Answer nutrients that are required in large quantities
- major elements in cell macromolecules (C, O, H, N, P, S)
- ions necessary for protein function (Mg^2+, Ca^2+, Fe^2+, K^+)
What are the 6 macronutrients that make up carbs, lipids, nucleic acids, and proteins of the
cell? - Answer carbon, nitrogen, phosphorus, hydrogen, oxygen, and sulfur
What are the 4 macronutrients that are cations and serve as cofactors? - Answer Mg^2+,
Fe^2+, K^+, Ca^2+
Cofactor - Answer a metallic ion or a coenzyme required by an enzyme to perform normal
catalysis
Micronutrients - Answer nutrients that are required in small quantities
- trace elements necessary for enzyme function (Co, Cu, Mn, Zn, Mo, Ni)
What are the 6 micronutrients? - Answer cobalt, copper, manganese, molybdenum, nickel,
and zinc
Heterotrophy - Answer the use of external source of organic carbon compounds for
biosynthesis
- releases CO2
- humans are heterotrophs
Autotrophy - Answer the metabolic reduction fo carbon dioxide to produce organic carbon for
,Organotrophy - Answer also called chemoorganotrophy or chemoheterotrophy; the metabolic
oxidation of organic compounds to yield energy without absorption of light
- most heterotrophs are organotrophs
- convert large amounts of organic carbon source to CO2, which is released into atmosphere
Photoautotrophy - Answer the fixation of single-carbon compounds into organic biomass,
using light as an energy source
Chemolithoautotrophy - Answer metabolism in which single-carbon compounds are fixed into
organic biomass, using energy from chemical reactions without light absorption
- most gain energy by oxidizing inorganic substances
Summary: classifications of microbes on basis of carbon and energy acquisition - Answer
AUTOTROPHS: fix CO2 into complex organic molecules; gain energy through either using light or
oxidizing inorganic compounds
- chemolithoautotroph: produce energy from oxidizing inorganic molecule
- photolithoautotroph: generate energy from light absorption
HETEROTROPHS: break down organic compounds from other organisms to gain energy; can be
divided into two classes based on whether light is involved
- chemoorganoheterotroph: obtain energy and carbon solely from organic compounds
- photoorganotroph: obtain energy from breakdown of organic compounds and through light
absorption
Membrane potential - Answer energy stored as an electrical voltage difference across a
membrane
- for most cell, membrane potential more negative inside than outside
- generated when energy used to pump protons, Na^+, or K^+ outside cell
Electrochemical potential - Answer a type of potential energy formed by the combined
concentration gradient of a molecule and the electrical potential across a membrane
, - energy stored in PMF can be used to move nutrients into cell, drive motors that rotate flagella,
and drive synthesis of ATP
ATP synthase - Answer a protein complex that synthesizes ATP from ADP and inorganic
phosphate using energy derived from the transmembrane proton potential; it is located in the
prokaryotic cell membrane and in the mitochondrial inner membrane
Nitrogen-fixing bacterium - Answer a bacterium that can reduce diatomic nitrogen gas (N2) to
two molecules of ammonium ion (NH4+)
- may be free-living in soil or water
- may form symbiotic relationships with plants/other organisms
Nitrification - Answer the oxidation of reduced nitrogen compounds back to nitrate or nitrite
Passive transport - Answer net movement of molecules across a membrane without energy
expenditure by the cell
- simple and facilitated diffusion
Active transport - Answer an energy-requiring process that moves molecules across a
membrane against their electrochemical gradient
- coupled transport
Facilitated diffusion - Answer a process of passive transport across a membrane that is
facilitated by transport proteins
- higher concentration to lower concentration only
- aquaporin family transports water and small polar molecules (glycerol)
Coupled transport - Answer the movement of a substance against its electrochemical gradient
(from lower to higher concentration, or from opposite charge to like charge) using the energy
provided by the simultaneous movement of a different chemical down its electrochemical
Auburn) Questions with Guaranteed
Pass Solutions 2025-2026 Updated.
Macronutrients - Answer nutrients that are required in large quantities
- major elements in cell macromolecules (C, O, H, N, P, S)
- ions necessary for protein function (Mg^2+, Ca^2+, Fe^2+, K^+)
What are the 6 macronutrients that make up carbs, lipids, nucleic acids, and proteins of the
cell? - Answer carbon, nitrogen, phosphorus, hydrogen, oxygen, and sulfur
What are the 4 macronutrients that are cations and serve as cofactors? - Answer Mg^2+,
Fe^2+, K^+, Ca^2+
Cofactor - Answer a metallic ion or a coenzyme required by an enzyme to perform normal
catalysis
Micronutrients - Answer nutrients that are required in small quantities
- trace elements necessary for enzyme function (Co, Cu, Mn, Zn, Mo, Ni)
What are the 6 micronutrients? - Answer cobalt, copper, manganese, molybdenum, nickel,
and zinc
Heterotrophy - Answer the use of external source of organic carbon compounds for
biosynthesis
- releases CO2
- humans are heterotrophs
Autotrophy - Answer the metabolic reduction fo carbon dioxide to produce organic carbon for
,Organotrophy - Answer also called chemoorganotrophy or chemoheterotrophy; the metabolic
oxidation of organic compounds to yield energy without absorption of light
- most heterotrophs are organotrophs
- convert large amounts of organic carbon source to CO2, which is released into atmosphere
Photoautotrophy - Answer the fixation of single-carbon compounds into organic biomass,
using light as an energy source
Chemolithoautotrophy - Answer metabolism in which single-carbon compounds are fixed into
organic biomass, using energy from chemical reactions without light absorption
- most gain energy by oxidizing inorganic substances
Summary: classifications of microbes on basis of carbon and energy acquisition - Answer
AUTOTROPHS: fix CO2 into complex organic molecules; gain energy through either using light or
oxidizing inorganic compounds
- chemolithoautotroph: produce energy from oxidizing inorganic molecule
- photolithoautotroph: generate energy from light absorption
HETEROTROPHS: break down organic compounds from other organisms to gain energy; can be
divided into two classes based on whether light is involved
- chemoorganoheterotroph: obtain energy and carbon solely from organic compounds
- photoorganotroph: obtain energy from breakdown of organic compounds and through light
absorption
Membrane potential - Answer energy stored as an electrical voltage difference across a
membrane
- for most cell, membrane potential more negative inside than outside
- generated when energy used to pump protons, Na^+, or K^+ outside cell
Electrochemical potential - Answer a type of potential energy formed by the combined
concentration gradient of a molecule and the electrical potential across a membrane
, - energy stored in PMF can be used to move nutrients into cell, drive motors that rotate flagella,
and drive synthesis of ATP
ATP synthase - Answer a protein complex that synthesizes ATP from ADP and inorganic
phosphate using energy derived from the transmembrane proton potential; it is located in the
prokaryotic cell membrane and in the mitochondrial inner membrane
Nitrogen-fixing bacterium - Answer a bacterium that can reduce diatomic nitrogen gas (N2) to
two molecules of ammonium ion (NH4+)
- may be free-living in soil or water
- may form symbiotic relationships with plants/other organisms
Nitrification - Answer the oxidation of reduced nitrogen compounds back to nitrate or nitrite
Passive transport - Answer net movement of molecules across a membrane without energy
expenditure by the cell
- simple and facilitated diffusion
Active transport - Answer an energy-requiring process that moves molecules across a
membrane against their electrochemical gradient
- coupled transport
Facilitated diffusion - Answer a process of passive transport across a membrane that is
facilitated by transport proteins
- higher concentration to lower concentration only
- aquaporin family transports water and small polar molecules (glycerol)
Coupled transport - Answer the movement of a substance against its electrochemical gradient
(from lower to higher concentration, or from opposite charge to like charge) using the energy
provided by the simultaneous movement of a different chemical down its electrochemical
