Anabolic reactions form bonds which require energy. Energy-requiring processes are known as ____.
Endergonic
Catabolic reactions break bonds releasing energy making the ____ reactions.
Exergonic
___ are proteins that increase probability of chemical reactions while themselves remaining unchanged.
Enzymes
What are 4 important characteristics of enzymes?
Reusable
Highly specific
Have an active site
Required in minute amts
What is meant by enzymes are reusable?
Once a reaction has occurred, enzyme is released to participate in another reaction
An enzyme that functions in 1 type of reaction will not usually participate in another making enzymes what?
Highly Specific
Each enzyme has an ____ ____ which is a pocket or cleft where a reaction takes place.
Active site
When a ___ binds to an enzyme's ___ ___ a chem reaction occurs to form one or more ____.
Substrate
Active site
Products
Why are enzymes only required in minute amts?
B/c they can be used thousands of time to catalyze the same reaction
The 3-D shape of an enzymes active site recognizes & holds a substrate in a what?
Enzyme-substrate complex
What happens to the substrate in an enzyme during hydrolysis?
Chem bonds are stretched or weakened causing them to break
In a synthesis reaction, what occurs at the enzyme-substrate complex?
Electron shells of substrates are forced to overlap where chem bond will form
What is activation energy and how do enzymes effect it?
Energy needed to start a reaction.
Enzyme lower it
The enzyme in human tears & saliva the hydrolyzes the bond between NAG & NAM in cell walls of Gram-pos bacterial cells is called ____.
Lysozyme
What are cofactors?
Small, nonprotein substances that participate in catalytic reactions
A small nonprotein organic molecule is referred to as a ____. 2 important ones are ___ & ___.
Coenzymes
NAD⁺ & FAD
What is the term given to a sequence of chem reactions where each reaction is catalyzed by a different enzyme & the product of one reaction is the substrate for the next.
Metabolic pathway
The products of reactions within a metabolic pathway are known as ____.
Intermediates
Metabolic pathways can be which of the following?
Catabolic
Anabolic
Either
Neither
Catabolic or anabolic
Why does temperature have an effect on an enzyme's action?
B/c enzymes are proteins and higher temps denature proteins
What are 3 ways we can inhibit the activity of enzymes?
Increase temp
Decrease pH
Apply chemicals such as alcohols or phenols
How does pathway modulation inhibit an enzyme?
Competitive or noncompetitive inhibition
Explain noncompetitive inhibition of an enzyme.
Final end product of a pathway binds to a nonactive site altering the shape of the active site so the substrate can no longer bind
Enzyme inhibition that is caused by blocking the active site so a substrate can not bind is known as what?
Competitive
What compound is known as cellular energy currency?
ATP
ATP os formed on the __ __ of bacterial & archaeal cells and in the ____ in eukaryotes.
Cell membrane
mitochondria
T or F; ATP molecules cannot be stored.
True
What are 3 characteristics that make ATP unstable?
3 phosphate grps have neg charge on O₂ atom
Like charges repel
Phos grps packed tightly together repelling each other
What is the result of breaking high energy bonds in ATP?
ADP + a phosphate grp
How much ATP does a typical bacterial cell require to satisfy its energy needs?
3 million ATP/sec
If we add a phosphate grp to a molecule we accomplish a process known as ___.
Phosphorylation
The molecular weight of a substance expressed in grams in known as a what?
Mole
Define a calorie.
Amt of heat required to raise 1g of H₂O 1⁰C
A mole of glucose contains about ____ calories of energy.
686,000
Virtually all cells make ATP by harvesting energy fr exergonic metabolic pathways in a process known as ___ ___.
Cellular Respiration
If cells consume oxygen making ATP then they practice ____ respiration.
Aerobic
The process of making ATP w/o the presence of oxygen is known as ___ respiration
Anaerobic
What is the chem equation for aerobic resp in obligate aerobes.
C₆H₁₂O₆ + 6 O₂ + 38 ADP + 38 P → 6 CO₂ + 6 H₂O + 38 ATP
What are the 3 stages of cellular respiration?
Glycolysis
Citric Acid Cycle
Oxidative Phosphorylation
T or F: Glycolysis can occur with or without oxygen.
True
In the first part of glycolysis 2 ATP are ___ & in the 2nd part 4 ATP are ___.
Hydrolyzed
Synthsized
What is the net gain of glycolysis?
2 ATP
2 NADH + H⁺
2 pyruvate molecules
The formation of ATP resulting fr the transfer of phosphate fr substrate to ADP is known as what?
Substrate Level Phosphorylation
What happens when a substance is reduced?
It goes through a process of gaining e⁻ prs
Why is the citric acid cycle called a cycle?
B/c the end product formed is used as 1 substrate to initiate the pathway
All reactions on the citric acid cycle are ___ by ___.
Catalyzed by enzymes
What is the pyruvate molecule's purpose in the citric acid cycle?
It starts the cycle going around again
The process of removing e⁻ prs fr a substance is known as ___.
Oxidation
Before pyruvate enters the Kreb's cycle, what happens to it?
Enzyme oxidizes a C atom fr each pyruvate molecule & releases them as CO₂ molecules
At the beginning of the Kreb's Cycle ____ atoms of pyruvate combine w/coenzyme A to form ___ __.
2 C atoms
Acetyl CoA
What happens to the last e⁻ fr pyruvate at the beginning of the Krebs cycle?
They are transferred along w/2 p⁺ to NAD⁺ to form NADH
For each molecule of C₆H₁₂O₆ what is produced by the Krebs cycle?
6 NADH + H⁺
2 FADH₂
2 ATP
4 CO₂
Out fr the Krebs cycle, what enters the ETC?
NADH + H⁺
FADH₂
Where does oxidative phosphorylation take place?
Cell membrane
What are the reactants for oxidative phosphorylation?
NADH
FADH
O₂
What are the products of oxidative phosphorylation?