Test One study guide Flashcards
(18 cards)
Define anabolism and give examples of reactions or pathways that are anabolic.
Anabolism is building tissues of energy storage molecules (requires energy input) - endergonic: gaining energy.
Define catabolism and give examples of reactions or pathways that are catabolic.
Catabolism is the breakdown of molecular substances to provide energy. Energy released from CHO, fats, and proteins -> H2O + CO2
What does it mean to say reactions are “coupled” and why is this important?
“Coupled” reactions to capture energy and deliver it to another system or structure. In the body, coupled reactions conserve a large portion of the chemical energy stored within the micronutrients.
Why are enzymes important to the metabolic processes?
Because they increase the rate of reactions. They are proteins that are biological catalysts. They aid in the process of digestion.
What role does ATP play in the body and why are we concerned with it’s formation?
ATP is the body’s substance for almost all biological work. It’s the primary energy molecule. We are concerned with the formation because the body can only store small amounts of ATP, therefore once we use it, it is important that we make more!
Describe the systems the body has to replenish the supply of ATP. Rank them in regard to how fast and how much they replenish.
1: phosphogenic reactions- a reservoir of energy. Very fast 60:40ratio
2: Glycolysis (2ATP anaerobic) breakdown of macronutrients.
3: Post glycolytic processing (28ATP)
4: B-oxidation (continuous)
Explain glycolysis, differentiate between the aerobic and anaerobic portions.
Glycolysis: metabolic breakdown of glucose. Anabolic: doesn’t require O2, happens in cytoplasm, produces 2 ATP per glucose, glucose-> pyruvate.
Aerobic: requires O2, happens in mitochondria, produces 30-32 ATP per glucose, pyruvate-> CO2 + H2O
Pyruvate is the end product of anaerobic glycolysis. What are the possible fates of pyruvate and the physical conditions that may determine that fate?
Fates: can be metabolized for energy in the mitochondria via Krebs cycle (anaerobic glycolysis)
- converted to lactate in order to maintain NAD/NADH ratio. - converted back into glucose (only during recovery) - converted into oxaloacetate.
What is the importance of lactate to the process of glycolysis? Fates of lactate once it has been formed.
Lactate is an indirect regulator of glycolysis. It is the enzyme of control. Possible fates: can be oxidized for energy. - can be transported to another muscle for oxidization. - transported to the liver for glyconeogenesis: cori cycle.
What is meant by the term “lactate threshold”?
Is the exercise intensity at which lactate starts to accumulate in the bloodstream.
Explain the Cori Cycle. Why is it important during exercise or recovery?
Cori cycle: lactate is transported from the muscle to the liver via bloodstream. Lactate is then oxidized to pyruvate in liver. Pyruvate is converted to glucose via glyconeogenesis. It is important by producing ATP during muscle recovery.
Describe the Krebs cycle and the ETC.
Krebs cycle: a series of reactions that allow pyruvate to be “burned” for maximum energy yield.
ETC: a group of enzymes and substances embedded within the mitochondrial membrane that produces ATP by combining H and O2
How do the Krebs cycle and ETC work together to produce ATP?
NADH,H and FADH2 are made in the Krebs cycle and then they go to the ETP where ATP is made. GTP is also made in this cycle and is used for energy in the mitochondria.
What are the products of Krebs cycle and how much ATP can be produced by them?
NADH,H - 2.5ATP
FADH2 - 1.5ATP
1 GTP = 1ATP
Describe lipolysis. Where are the lipids stored in the body?
Is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and 3 fatty acids. Lipids as fatty acids are stored in fat cells. Triglycerides are stored in blood.
Describe the process of beta-oxidation. What are the products of this reaction and how are they turned into ATP?
FA chains are broken down into two carbon units with the help of co-enzyme A. - Each CoA, when metabolized, will produce 10ATP - 1NADH,H and FADH are produced from B-oxidation.
What are the conditions that cause proteins to be broken down for energy? What happens to amine that must be removed? What happens to the carbon skeletons?
Conditions: excess dietary protein is consumed. - during long, intense exercise. - when overtrained. - when CHO is limited.
-> AA must have nitrogen removed
->Carbon skeletons: ketogenic aa form acetyl groups.
Glucogenic aa can be converted into pyruvate.
What energy storage substances must be replenished during recovery from a long, or high intensity, training session?
Replenish these energy storage substances after exercise:
- glycogen storage
- triglyceride storage
- amino acid and protein synthesis
