UMICH BIOCHEM 212 EXAM 3 STUDYGUIDE QUESTIONS AND CORRECT
ANSWERS
Question:
1. what is the ultimate source of energy on our planet
Answer:
The sun
Question:
2. How do plants an animals depend on each other for energy
Answer:
plants release o2 in to the atmosphere for animals to take in for cellular respiration which
produce co2 which is them taken back by the plants to complete photosynthesis
Question:
3. what are the energy requirements for life
Answer:
1. energy must be released from food gradually 2. energy must be stored in readily accessible
forms 3. release of energy from storage must be finely controlled so that it is available exactly
when and where its needed 4. just enough energy must be released to maintain body
temperature 5. energy in a form other than heat must be available to drive chemical reactions
that are not favorable at body temperatures
Question:
4. what are the roles of the four stages of catabolism
Answer:
stage one: digestion of macro-molecules into subunits stage two: breakdown of subunits into an
oxidized form (acetyl-SCoA) stage three: acetyl-scoa oxidized to produce co2 and reduced
enzymes stage four: oxidative phosphorylation to produce ATP and H2O
Question:
5. What is the difference between endergonic and exergonic reactions
Answer:
endergonic: positive delta G, reactions require energy to occur, are nonspontaneous Exergonic:
negative delta G, reactions give off energy, occur spontaneously
Question:
6. why are endergonic reactions coupled to exergonic reactions four principles of metabolic
pathways
Answer:
endergonic reactions do not have enough energy to proceed with the reactions so being coupled
with an exergonic reaction gives the needed energy to go through with a reaction pathway has a
committed step 3. all metabolic pathways are regulated (prevents build up of metabolites and
waste of energy) 4. metabolic pathways in eukaryotic cells occur in specific cellular locations
,(glycolysis: cytosol, TCA: Mitochondrial matrix, electron transport chain: inner mitochondrial
membrane)
Question:
7. what are the three types of metabolic pathways
Answer:
1. Linear sequence: pathway follows a linear progression of reactions 2. cyclic sequence:
pathway regenerates initial substrate in last reaction 3. spiral sequence: one enzyme or group of
enzymes breakdown a polymer one monomer at a time
Question:
8. what molecules are considered high energy
Answer:
acetyl-CoA, NADH, FADH2, ATP
Question:
9. What are the oxidized and reduced forms of FAD and NAD
Answer:
NAD+/NADH, FAD/FADH2
Question:
10. what roles do vitamins play in energy production
Answer:
the provide coenzymes, coenzymes are required for catalysis
Question:
11. why is ATP used as the energy currency in the cell
Answer:
1. ATP hydrolysis produces a medium amount of energy 2. stable at ph 7 3. requires an enzyme
for hydrolysis (others automatically breakdown in water) 4. easy bond to cleave 5. precursor for
other high energy molecules 6. universal energy that works in all cells
Question:
12. what is a coupled reaction and why do we need them ence between mono-, di- and
polysaccharides
Answer:
When an endergonic and exergonic reaction combine and we need them because some body
processes aren't exergonic on their own. so a coupled reaction will achieve a total free energy
change that is negative smaller sugar, disaccharide: a carbohydrate that is composed of two
monosaccharides, polysaccharide: complex carbohydrate which is a polymer of a
monosaccharide
Question:
13. what is the difference between an aldose and a ketose
, Answer:
Aldose: a hemiacetal hydroxyl group that contains a aldehyde, ketose: a hemiacetal hydroxyl
group that contains a ketone group
Question:
14. name the three different types of carbohydrate isomers
Answer:
1. D and L isomers (D form is most prevalent form in nature) 2. diastereomers 3. Anomers
Question:
15. given a pair of isomers can you identify the type of isomer that defines the pair
Answer:
Question:
16. what is the difference between a reducing sugar and a non-reducing sugar
Answer:
a reducing sugar has a carbohydrate with an anomeric carbon as part of a hemiacetal group. a
reducing sugar can cause other chemicals to be reduced
Question:
17. what is the purpose of the glucose oxidase test
Answer:
to measure the amount of glucose in blood or urine
Question:
18. what is a glycosidic bond and fined in terms of alpha/beta linkages
Answer:
ride and -OR group. alpha linkage: a hydroxyl group that is in the alpha position, beta linkage:
hydroxyl group is in the beta position
Question:
19. what three disaccharides are formed from the monosaccharides glucose, fructose and
galactose
Answer:
alpha D- glucose + alpha D-glucose = Maltose, beta D-glucose+ beta D-galactose = lactose,
alpha D-glucose + beta D-fructose = sucrose
Question:
20. what are the glycosidic linkages that are formed in the three disaccharides
Answer:
Maltose: alpha 1,4 linkage , lactose: beta 1,4 linkage, Sucrose: alpha 1, beta 2 linkage
Question:
21. which artificial sweetener resembles sucrose
ANSWERS
Question:
1. what is the ultimate source of energy on our planet
Answer:
The sun
Question:
2. How do plants an animals depend on each other for energy
Answer:
plants release o2 in to the atmosphere for animals to take in for cellular respiration which
produce co2 which is them taken back by the plants to complete photosynthesis
Question:
3. what are the energy requirements for life
Answer:
1. energy must be released from food gradually 2. energy must be stored in readily accessible
forms 3. release of energy from storage must be finely controlled so that it is available exactly
when and where its needed 4. just enough energy must be released to maintain body
temperature 5. energy in a form other than heat must be available to drive chemical reactions
that are not favorable at body temperatures
Question:
4. what are the roles of the four stages of catabolism
Answer:
stage one: digestion of macro-molecules into subunits stage two: breakdown of subunits into an
oxidized form (acetyl-SCoA) stage three: acetyl-scoa oxidized to produce co2 and reduced
enzymes stage four: oxidative phosphorylation to produce ATP and H2O
Question:
5. What is the difference between endergonic and exergonic reactions
Answer:
endergonic: positive delta G, reactions require energy to occur, are nonspontaneous Exergonic:
negative delta G, reactions give off energy, occur spontaneously
Question:
6. why are endergonic reactions coupled to exergonic reactions four principles of metabolic
pathways
Answer:
endergonic reactions do not have enough energy to proceed with the reactions so being coupled
with an exergonic reaction gives the needed energy to go through with a reaction pathway has a
committed step 3. all metabolic pathways are regulated (prevents build up of metabolites and
waste of energy) 4. metabolic pathways in eukaryotic cells occur in specific cellular locations
,(glycolysis: cytosol, TCA: Mitochondrial matrix, electron transport chain: inner mitochondrial
membrane)
Question:
7. what are the three types of metabolic pathways
Answer:
1. Linear sequence: pathway follows a linear progression of reactions 2. cyclic sequence:
pathway regenerates initial substrate in last reaction 3. spiral sequence: one enzyme or group of
enzymes breakdown a polymer one monomer at a time
Question:
8. what molecules are considered high energy
Answer:
acetyl-CoA, NADH, FADH2, ATP
Question:
9. What are the oxidized and reduced forms of FAD and NAD
Answer:
NAD+/NADH, FAD/FADH2
Question:
10. what roles do vitamins play in energy production
Answer:
the provide coenzymes, coenzymes are required for catalysis
Question:
11. why is ATP used as the energy currency in the cell
Answer:
1. ATP hydrolysis produces a medium amount of energy 2. stable at ph 7 3. requires an enzyme
for hydrolysis (others automatically breakdown in water) 4. easy bond to cleave 5. precursor for
other high energy molecules 6. universal energy that works in all cells
Question:
12. what is a coupled reaction and why do we need them ence between mono-, di- and
polysaccharides
Answer:
When an endergonic and exergonic reaction combine and we need them because some body
processes aren't exergonic on their own. so a coupled reaction will achieve a total free energy
change that is negative smaller sugar, disaccharide: a carbohydrate that is composed of two
monosaccharides, polysaccharide: complex carbohydrate which is a polymer of a
monosaccharide
Question:
13. what is the difference between an aldose and a ketose
, Answer:
Aldose: a hemiacetal hydroxyl group that contains a aldehyde, ketose: a hemiacetal hydroxyl
group that contains a ketone group
Question:
14. name the three different types of carbohydrate isomers
Answer:
1. D and L isomers (D form is most prevalent form in nature) 2. diastereomers 3. Anomers
Question:
15. given a pair of isomers can you identify the type of isomer that defines the pair
Answer:
Question:
16. what is the difference between a reducing sugar and a non-reducing sugar
Answer:
a reducing sugar has a carbohydrate with an anomeric carbon as part of a hemiacetal group. a
reducing sugar can cause other chemicals to be reduced
Question:
17. what is the purpose of the glucose oxidase test
Answer:
to measure the amount of glucose in blood or urine
Question:
18. what is a glycosidic bond and fined in terms of alpha/beta linkages
Answer:
ride and -OR group. alpha linkage: a hydroxyl group that is in the alpha position, beta linkage:
hydroxyl group is in the beta position
Question:
19. what three disaccharides are formed from the monosaccharides glucose, fructose and
galactose
Answer:
alpha D- glucose + alpha D-glucose = Maltose, beta D-glucose+ beta D-galactose = lactose,
alpha D-glucose + beta D-fructose = sucrose
Question:
20. what are the glycosidic linkages that are formed in the three disaccharides
Answer:
Maltose: alpha 1,4 linkage , lactose: beta 1,4 linkage, Sucrose: alpha 1, beta 2 linkage
Question:
21. which artificial sweetener resembles sucrose
