WorksheetsMicrobial Metabolism
Total questions: 85
Worksheet time: 43mins
What process converts nutrients into precursor molecules and releases energy stored as ATP?
Anabolism
Catabolism
Photosynthesis
Fermentation
What molecule is produced when energy is stored during catabolism?
ADP
ATP
Glucose
Oxygen
During anabolism, larger building blocks are formed from ________ molecules using energy.
precursor
waste
toxic
complex
Refer to the diagram of microbial metabolism. Which of the following is NOT a result of anabolism?
Macromolecules
Cellular structures
Energy lost as heat
Larger building blocks
Refer to the diagram of microbial metabolism. What are two cellular processes that use energy stored in macromolecules?
Cell growth and cell division
Photosynthesis and fermentation
DNA replication and protein denaturation
Osmosis and diffusion
Metabolism: Although microbial metabolism can cause disease and food spoilage, many pathways are ______ rather than pathogenic.
beneficial
harmful
toxic
infectious
Which of the following facilitate metabolic reactions?
Enzymes
Vitamins
Antibiotics
ATP
KEY CONCEPTS: ATP is used by microbes and other cells to manage ______ needs. (Fill in the blank)
energy
structural
genetic
sensory
KEY CONCEPTS: Catabolic reactions couple with ATP ______.
synthesis
hydrolysis
degradation
oxidation
KEY CONCEPTS: Anabolic reactions couple with ATP ______.
breakdown
synthesis
storage
release
What is the sum of controlled biochemical reactions within cells of an organism called?
Catabolism
Anabolism
Metabolism
Photosynthesis
The ultimate function of metabolism is to ________ the organism.
reproduce
digest
move
respire
Anabolic pathways synthesize large molecules from the smaller products; these pathways are ________ (require more energy than they release).
endergonic
exergonic
catabolic
spontaneous
Refer to the diagram labeled Fig. 8.2. Which process releases energy?
Catabolism
Anabolism
Metabolic Processes Guided by Eight Elementary Statements: Every cell acquires ________.
nutrients
waste products
light energy
toxins
Metabolic Processes Guided by Eight Elementary Statements: Energy is stored in ________ triphosphate (ATP).
adenosine
cytosine
guanine
thymine
Metabolism requires energy from light or ________ of nutrients.
catabolism
photosynthesis
osmosis
anabolism
Metabolic Processes Guided by Eight Elementary Statements: Cells ________ nutrients to form precursor metabolites.
catabolize
synthesize
excrete
absorb
Metabolic Processes Guided by Eight Elementary Statements: Precursor metabolites, energy from ATP, and enzymes are used in ________ reactions.
anabolic
catabolic
hydrolytic
oxidative
Metabolic Processes Guided by Eight Elementary Statements: ________ plus ATP form macromolecules.
Enzymes
Hormones
Vitamins
Minerals
Metabolic Processes Guided by Eight Elementary Statements: Cells grow by assembling ________.
macromolecules
organelles
hormones
vitamins
Metabolic Processes Guided by Eight Elementary Statements: Cells reproduce once they have ________ in size.
doubled
halved
tripled
remained the same
Based on the diagram, which process builds complex molecules from simple molecules?
anabolism
catabolism
Fill in the blank: The transfer of electrons from one molecule (donor) to another (acceptor) is known as __________ and __________ reactions (Redox).
oxidation, reduction
hydrolysis, condensation
phosphorylation, dephosphorylation
synthesis, degradation
Which of the following is an important electron carrier that is reduced from NAD+ to NADH?
Flavine adenine dinucleotide (FAD)
Nicotinamide adenine dinucleotide (NAD+)
Nicotinamide adenine dinucleotide phosphate (NADP+)
Glucose
Fill in the blank: Nicotinamide adenine dinucleotide phosphate (NADP+) is reduced to __________.
NADPH
NADH
ATP
FADH2
Fill in the blank: Flavine adenine dinucleotide (FAD) is reduced to __________.
FADH2
NADH
ATP
CO2
What happens to the electron donor during oxidation?
It gains an electron
It loses an electron
It becomes reduced
It becomes an acceptor
Refer to the diagram of the REDOX reaction. What is the role of the electron acceptor?
To lose an electron
To gain an electron
To become oxidized
To donate an electron
Refer to the diagram of the REDOX reaction. Fill in the blank: The process in which an electron is gained is called ________.
Reduction
Oxidation
Combustion
Neutralization
Refer to the diagram of the REDOX reaction. What does the mnemonic 'OIL RIG' stand for?
Oxidation Is Loss, Reduction Is Gain
Oxidation Is Gain, Reduction Is Loss
Oxygen Is Lost, Reduction Is Gained
Oxidation Increases, Reduction Increases
What is the process called when an organic phosphate is added to a substrate?
Phosphorylation
Hydrolysis
Oxidation
Methylation
Organisms release energy from nutrients; this energy can be concentrated and stored in high-energy phosphate bonds of which molecule?
Glucose
ATP
CO2
Polysaccharide
Which process is responsible for converting glucose to CO2, H2O, and heat?
Bond formation
Glycolysis, Krebs cycle, oxidative phosphorylation
Phosphorylation
Polysaccharide synthesis
In the context of ATP production and energy storage, what are the products of glycolysis, Krebs cycle, and oxidative phosphorylation as shown in the diagram?
CO2, H2O, and heat
Glucose, O2, and ATP
Lactic acid, NADH, and FADH2
Pyruvate, acetyl-CoA, and ADP
What is phosphorylation?
The removal of a phosphate group from a substrate
The addition of an organic phosphate to a substrate
The conversion of ATP to ADP
The breakdown of glucose
Cells phosphorylate ADP to ATP in three ways. Which of the following is NOT one of those ways?
Substrate-level phosphorylation
Oxidative phosphorylation
Photophosphorylation
Hydrolytic phosphorylation
Fill in the blank: Anabolic pathways use some energy of ATP by ______ a phosphate bond.
breaking
forming
sharing
stabilizing
Which of the following is a way that cells phosphorylate ADP to ATP?
Substrate-level phosphorylation
Glycolytic phosphorylation
Hydrolytic phosphorylation
None of the above
What happens when a substrate enters the active site of an enzyme?
The enzyme is destroyed
The substrate is converted to products
The enzyme/substrate complex forms
The substrate enters the active site of the enzyme
What forms when the enzyme changes shape slightly as the substrate binds?
Products
Enzyme/substrate complex
Substrate
Active site
What happens to the substrate in the enzyme/substrate complex?
It leaves the enzyme
It is converted to products
It binds to another enzyme
It is destroyed
What happens after products are formed in the enzyme reaction?
Products leave the active site of the enzyme
Products bind to the enzyme
Enzyme is destroyed
Substrate re-enters the enzyme
Which class of enzyme catalyzes hydrolysis (catabolic) reactions?
Hydrolase
Ligase
Isomerase
Oxidoreductase
Which class of enzyme is responsible for the rearrangement of atoms within a molecule (neither catabolic nor anabolic)?
Isomerase
Ligase
Hydrolase
Oxidoreductase
Which enzyme class joins two or more chemicals together (anabolic)?
Ligase or Polymerase
Hydrolase
Oxidoreductase
Isomerase
Which enzyme class splits a chemical into smaller parts without using water (catabolic)?
Lyase
Hydrolase
Ligase
Oxidoreductase
Which enzyme class transfers electrons or hydrogen atoms from one molecule to another?
Oxidoreductase
Transferase
Hydrolase
Ligase
Which enzyme class moves a functional group from one molecule to another (may be anabolic)?
Transferase
Ligase
Hydrolase
Isomerase
What is a catalyst?
A substance that slows down a chemical reaction
A substance that helps speed up a chemical reaction
A type of protein that stores energy
A molecule that inhibits enzymes
Many protein enzymes are complete in themselves.
True
False
What are apoenzymes?
Protein portions of enzymes that are active without cofactors
Protein portions of enzymes that are inactive if not bound to non-protein cofactors
Non-protein molecules that help enzymes
RNA molecules that act as enzymes
Fill in the blank: Apoenzyme + cofactor(s) = _________.
holoenzyme
apoenzyme
substrate
prosthetic group
Most enzymes are proteins. Some RNA molecules that act as enzymes are called _________
ribozymes
liposomes
lysosomes
chromosomes
What happens when a cofactor or coenzyme binds to an apoenzyme?
The enzyme becomes inactive
The enzyme becomes active
The substrate is destroyed
The enzyme is denatured
What is the main effect of an enzyme on a chemical reaction as shown in the diagram?
It increases the activation energy
It decreases the activation energy
It changes the products formed
It increases the initial energy level
Refer to the diagram titled 'Chemical Reactions using Enzymes'. Complete the reaction equation shown in the diagram: AB → ___ + ___.
A + B
AB2
A2 + B2
A + AB
Refer to the diagram titled 'Chemical Reactions using Enzymes'. Which line on the graph represents the reaction with an enzyme?
The solid line
The dashed line
Refer to the diagram titled 'Chemical Reactions using Enzymes'. True or False: The activation energy required for a reaction is lower when an enzyme is present.
True
False
At what temperature does enzyme activity reach its peak according to the graph?
Around 37°C
Around 20°C
Around 50°C
Around 10°C
At what pH does enzyme activity reach its maximum according to the graph?
Around pH 7
Around pH 3
Around pH 10
Around pH 12
Refer to the graph labeled (c) Substrate concentration. What happens to enzyme activity as substrate concentration increases beyond the saturation point?
It continues to increase
It decreases
It levels off
It drops to zero
Refer to the diagram titled 'Protein Conformation relates to Functionality.' Which of the following best describes the difference between a functional protein and a denatured protein?
A) A functional protein has a specific three-dimensional shape, while a denatured protein has lost its shape.
B) Both functional and denatured proteins have the same shape.
C) A denatured protein is more functional than a functional protein.
D) A functional protein is always linear.
Refer to the diagram titled 'Protein Conformation relates to Functionality.' Fill in the blank: The functionality of a protein is directly related to its _________
conformation (shape)
color
temperature
mass
Which of the following is NOT a factor influencing enzyme activity?
Temperature
pH
Substrate concentration
Light intensity
Fill in the blank: ________ fill the active site of an enzyme and block the substrate.
Competitive inhibitors
Noncompetitive inhibitors
Allosteric activators
Cofactors
Which of the following statements is TRUE about sulfa drugs?
They bind to the active site of an enzyme within the bacterial folic acid synthesis pathway.
They promote bacterial growth.
They help bacteria synthesize DNA, RNA, and proteins.
They are a type of substrate.
The main difference between sulfanilamide and PABA based on their chemical structure is:
Sulfanilamide has an amine group instead of a carboxylic acid group.
Sulfanilamide has a benzene ring while PABA does not.
PABA contains a sulfur atom, but sulfanilamide does not.
PABA has an extra methyl group compared to sulfanilamide.
Refer to the diagram showing normal binding of substrate and action of enzyme inhibitors. In the presence of a competitive inhibitor, what happens to the substrate?
The substrate binds to the active site
The substrate is blocked from binding to the active site
The substrate is converted to product
The enzyme is destroyed
What is the site, other than the active site, used to regulate enzyme activity called?
Substrate site
Allosteric site
Catalytic site
Inhibitor site
Binding an allosteric molecule induces a conformational change that ______ the affinity of the enzyme for its substrate.
reduces
increases
eliminates
stabilizes
Which of the following best describes the key regulation of metabolic pathways involved in both catabolism and anabolism?
Allosteric regulation
Competitive inhibition
Feedback inhibition
Substrate-level phosphorylation
What is feedback inhibition?
The use of a pathway product to regulate its own further production
The use of an enzyme to speed up a reaction
The breakdown of substrates into products
The conversion of energy in a cell
What happens when the end-product binds to the allosteric site of Enzyme 1?
The pathway shuts down due to feedback inhibition.
The enzyme becomes more active and speeds up the pathway.
The substrate is converted directly into the end-product.
The end-product is broken down by Enzyme 1.
Fill in the blank: In feedback inhibition, the _______ acts as an allosteric inhibitor to shut down the pathway.
end-product
substrate
enzyme
cofactor
Which of the following amino acids are regulated by feedback inhibition in the pathway shown in the diagram?
Tyrosine, Phenylalanine, Tryptophan
Glucose, Fructose, Sucrose
Alanine, Glycine, Serine
Lysine, Methionine, Threonine
Feedback inhibition is a mechanism that allows a metabolic pathway to continue producing end-products without any regulation.
True
False
Eukaryotic cells isolate enzymes of different metabolic pathways within _________.
membrane-bounded organelles
cytoplasm
ribosomes
cell wall
Cells use ________ sites on enzymes to control activity of enzymes.
allosteric
active
substrate
binding
Feedback inhibition slows/stops ________ pathways when product is in abundance.
anabolic
catabolic
metabolic
glycolytic
Cells regulate amphibolic pathways by requiring different ________ for each pathway.
coenzymes
hormones
nucleotides
lipids
Fill in the blank: Cells ______ or degrade channel and transport proteins.
synthesize
destroy
absorb
replicate
Fill in the blank: Cells often synthesize enzymes only when ______ is available.
substrate
enzyme
product
cofactor
Fill in the blank: Cells catabolize the more ______-efficient choice if two energy sources are available.
energy
time
cost
space
Fill in the blank: Cells synthesize metabolites they need, cease synthesis if ______ is available.
metabolite
enzyme
protein
hormone
