HBIO 320 EXAM 2 - BIOENERGENICS EXAM QUESTIONS
AND ANSWERS WITH COMPLETE SOLUTIONS GRADED
How is NAD+ reformed after NADH is formed in glycolysis?
1. NADH (+H) is shuttled into mitochondria for ETC, forms NAD+ which is shuttled back
to sarcoplasm
2. Pyruvate can accept hydrogen and form lactate (driven by lactate dehydrogenase)
What is metabolism?
Totality of cellular reactions including anabolic (+) and catabolic (-) reactions
Bioenergetics
Metabolic processes converting nutrients (food) into energy
What are enzymes? What do they do?
- Proteins that regulate speed of reaction
- Lower the activation energy of the reaction, but reaction must already want to happen
(must be possible)
What is a kinase?
Adds a phosphate group
What is a phosphatase?
Removes a phosphate group
What is a dehydrogenase
Removes a hydrogen
What is an oxidase?
, Catalyzes a redox reaction
What is an isomerase?
Rearranges molecules
What is Vmax of an enzyme?
- Maximal rate of enzymatic activity
- All enzymes are saturated and rate of rxn does not increase when more substrate is
added
What is Km of an enzyme?
- Substrate concentration where one-half maximal activity is achieved
- Low Km = enzyme is good and effective at using substrate
What are the two physiological conditions that influence the activity of enzymes?
- pH and Temperature
- Homeostaticly regulated conditions, keep enzymes working and prevents denaturing
What is glycogen?
- Polysaccharide found in animal tissue
- Made of glucose, linked via glycogen synthase
- Storage unit
- Muscle glycogen = only usable by muscle
- Liver glycogen = release glucose for all tissues
Why do we store more fat than carbohydrates?
- Higher ratio of carbon to oxygen compared to carbs
- more compact = more fats stored than glycogen
How is fat stored in the body?
AND ANSWERS WITH COMPLETE SOLUTIONS GRADED
How is NAD+ reformed after NADH is formed in glycolysis?
1. NADH (+H) is shuttled into mitochondria for ETC, forms NAD+ which is shuttled back
to sarcoplasm
2. Pyruvate can accept hydrogen and form lactate (driven by lactate dehydrogenase)
What is metabolism?
Totality of cellular reactions including anabolic (+) and catabolic (-) reactions
Bioenergetics
Metabolic processes converting nutrients (food) into energy
What are enzymes? What do they do?
- Proteins that regulate speed of reaction
- Lower the activation energy of the reaction, but reaction must already want to happen
(must be possible)
What is a kinase?
Adds a phosphate group
What is a phosphatase?
Removes a phosphate group
What is a dehydrogenase
Removes a hydrogen
What is an oxidase?
, Catalyzes a redox reaction
What is an isomerase?
Rearranges molecules
What is Vmax of an enzyme?
- Maximal rate of enzymatic activity
- All enzymes are saturated and rate of rxn does not increase when more substrate is
added
What is Km of an enzyme?
- Substrate concentration where one-half maximal activity is achieved
- Low Km = enzyme is good and effective at using substrate
What are the two physiological conditions that influence the activity of enzymes?
- pH and Temperature
- Homeostaticly regulated conditions, keep enzymes working and prevents denaturing
What is glycogen?
- Polysaccharide found in animal tissue
- Made of glucose, linked via glycogen synthase
- Storage unit
- Muscle glycogen = only usable by muscle
- Liver glycogen = release glucose for all tissues
Why do we store more fat than carbohydrates?
- Higher ratio of carbon to oxygen compared to carbs
- more compact = more fats stored than glycogen
How is fat stored in the body?
