Alcamo's Ch 6
Card Set Information
Alcamo's Ch 6
Alcamo's Microbiology Ch 6
What is the term that refers to all biochemical reactions taking place in an organism?
Anabolism does what?
Builds larger organic compounds (carbs & proteins) fr simpler monomers
___ hydrolyzes polymers into simpler molecules.
Anabolic reactions form bonds which require energy. Energy-requiring processes are known as ____.
Catabolic reactions break bonds releasing energy making the ____ reactions.
___ are proteins that increase probability of chemical reactions while themselves remaining unchanged.
What are 4 important characteristics of enzymes?
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?
Each enzyme has an ____ ____ which is a pocket or cleft where a reaction takes place.
When a ___ binds to an enzyme's ___ ___ a chem reaction occurs to form one or more ____.
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?
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 ____.
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 ___ & ___.
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.
The products of reactions within a metabolic pathway are known as ____.
Metabolic pathways can be which of the following?
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?
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?
What compound is known as cellular energy currency?
ATP os formed on the __ __ of bacterial & archaeal cells and in the ____ in eukaryotes.
T or F; ATP molecules cannot be stored.
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 ___.
The molecular weight of a substance expressed in grams in known as a what?
Define a calorie.
Amt of heat required to raise 1g of H₂O 1⁰C
A mole of glucose contains about ____ calories of energy.
Virtually all cells make ATP by harvesting energy fr exergonic metabolic pathways in a process known as ___ ___.
If cells consume oxygen making ATP then they practice ____ respiration.
The process of making ATP w/o the presence of oxygen is known as ___ respiration
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?
Citric Acid Cycle
T or F: Glycolysis can occur with or without oxygen.
In the first part of glycolysis 2 ATP are ___ & in the 2nd part 4 ATP are ___.
What is the net gain of glycolysis?
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 ___.
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
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⁺
Out fr the Krebs cycle, what enters the ETC?
NADH + H⁺
Where does oxidative phosphorylation take place?
What are the reactants for oxidative phosphorylation?
What are the products of oxidative phosphorylation?
What 3 pathways are aerobic?
Oxidative phosphorylation occurs during ___ respiration.
anaerobic & aerobic
Anaerobic & Aerobic
Oxidative phosphorylation occurs where?
Electron Transport Chain
What are the products of anaerobic oxidative phosphorylation?
ATP, Nitrate, H₂S, Methane
Name 4 bacteria where fermentation takes place.
What are the 2 pathways involved with fermentation?
Where do the pathways in fermentation take place?
In the cytosol
What are the reactants for the fermentation pathway?
What are the products of the fermentation pathway?
What are the 2 reactions in photosnthesis?
Energy fixing (light) reactions
Carbon fixing reactions (Calvin cycle)
The energy fixing reactions of photosynthesis take place in the ___ ___ where as the Calvin cycle goes on in the ___.
The reactants for the energy fixing reactions are ___, ___ ___ & ___.
The products of the energy fixing or light reactions are ___ & ___.
What are the 4 reactants of the Calvin cycle?
What are the products of the Calvin cycle?
Glycolysis is the splitting of 1 ___ into 2 ___ molecules.
B/f entering the Kreb's cycle enzymes do what?
Remove a C fr each pyruvate molecule
Combine the carbon with coenzyme A (CoA) to form acetyl-CoA
The Krebs cycle is like a constantly turning wheel doing what?
Picking up pyruvate molecules from glycolysis
Spitting out carbon dioxide, ATP, NADH, and FADH2
The ETC is composed of electron carriers called ___ which are made of ___.
___ accepts the electron pr at the end of the chain, acquires 2 protons & becomes ___.
As the electrons move down the chain they use ___, which is harnessed to ___ ___ out of the cell in a process called ___.
Protons outside the membrane of the ETC create a ___ ___.
ATP synthase harnesses the energy fr the flowing protons to what?
Phosphorylate ADP into ATP
__ __ are those compounds that provide high energy electrons. 3 examples are ___, ___ & ___.
Carbohydrates, lipids, proteins
Compounds that accept low energy electrons, after their energy has been used are called what?
What is the electron donor in aerobic, anaerobic & fermentation pathways?
The electron acceptors in aerobic pathways is what?
What are the electron acceptors in anaerobic pathways?
What is the product of aerobic pathways?
What are the products of anaerobic pathways?
Organic compounds used as electrons donors include what compounds?
Reactions in cyanobacteria utilize which chlorophyll?
Reactions in sulfur bacteria utilize which chlorophyll?
Bacteriochlorophyll a & b
Reactions in archaebacteria utilize which chlorophyll?
Photosynthesis in eukaryotes utilize which types of chlorophyll?
Chlorophyll a & b
Organisms that are autotrophs ___ their own food & use what as their carbon source?
Organisms that are heterotrophs obtain ___ food taking in preformed ___ ___.
What are 3 types of heterotrophs?
Where do saprobes get organic nutrients from?
Non-living sources (dead things)
Parasites obtain nutrients from ___ ___.
Pathogens are ___-___ organisms.
In anaerobic resp, anaerobes use molecules ___ ___ ___ as the final electron receptor in the ETC.
Other than oxygen
T or F: Anaerobic resp produces less ATP than aerobic resp.
Fermentation is used when ___ & other ___ ___ ___ are unavailable.
Alternative electron acceptors
What gets converted to lactic acid to reform NAD+ coenzymes so glycolysis can produce ATP fr glucose?
What is an example of eukaryotes performing fermentation?
Yeast used to ferment alcoholic beverages
In photosynthesis, ___ energy is converted to ___ energy to be stored as an organic compound.
Photosynthesis in prokaryotes is carried out in the ___ ___ & in eukaryotes in organelles called ___.
What is it in chlorophyll a that absorbs light energy?