Body Growth and Energy Flashcards
What is metabolism?
Metabolism encompasses all chemical reactions in the body that are essential for energy transfer and maintaining life.
What is a calorie?
A calorie is the unit of energy needed to raise the temperature of 1 gram of water by 1 degree Celsius.
How are carbohydrates processed in the body?
Carbohydrates are converted into glucose, which serves as the primary fuel for the body.
What happens to excess glucose in the body?
Excess glucose is stored as glycogen in the liver and muscles.
Which hormones regulate blood glucose levels?
Insulin and glucagon are the two key hormones that regulate blood glucose levels.
What occurs when glycogen stores are depleted?
When glycogen stores are depleted, the body begins to use fats as an energy source.
What is glycolysis?
Glycolysis is the process of breaking down glucose into two pyruvate molecules in the cytoplasm.
What are the two pathways pyruvate can take after glycolysis?
Pyruvate can undergo aerobic metabolism to become acetyl CoA or anaerobic metabolism to be converted into lactate.
What is gluconeogenesis?
Gluconeogenesis is the process of creating new glucose from lactate in the liver, particularly during anaerobic conditions.
What is glycogenolysis?
Glycogenolysis is the breakdown of glycogen into glucose, regulated by glucagon.
How does lipolysis function?
Lipolysis is the breakdown of stored triglycerides into glycerol and three fatty acids, with glycerol entering the glycolysis pathway.
What happens during fatty acid oxidation?
Fatty acids undergo beta oxidation in the mitochondria to form acetyl CoA, which then enters the Krebs cycle.
What is ATP and why is it important?
ATP (adenosine triphosphate) is the primary energy carrier in cells. It links energy intake from food with the work done by the body.
What role does the sodium-potassium pump play in cellular function?
The sodium-potassium pump uses ATP hydrolysis to move sodium out of the cell and potassium into the cell against their concentration gradients.
Describe the mechanism of muscle contraction.
Muscle contraction involves the sliding of actin and myosin filaments, forming crossbridges. ATP is required for the detachment of these filaments, and the process is calcium-dependent.
How do cells grow and repair?
Cells grow and repair through processes such as cell enlargement or proliferation (dividing of cells).
What is the primary fuel source for red blood cells?
Glucose is the only fuel for red blood cells, necessitating a constant supply of glucose in the body.
What happens during anaerobic metabolism when oxygen is not present?
In anaerobic metabolism, pyruvate is converted into lactate, which is then transported to the liver for gluconeogenesis.
What is the process of glycogenesis?
Glycogenesis is the formation of glycogen from glucose, which is regulated by the hormone insulin.
What are ketone bodies, and when are they used?
Ketone bodies are produced during ketogenesis and can be used as an alternative energy source when glucose availability is low.
How is energy released from food?
Energy is released from food by breaking the chemical bonds in food molecules, which is then converted into ATP.
Why can’t ATP be stored for long periods?
ATP cannot be stored for long because it is continuously used for energy, and the body relies on constant production from metabolic processes.
What is the significance of oxidative phosphorylation?
Oxidative phosphorylation is a key process in cellular respiration that produces large amounts of ATP, along with CO2 and H2O as waste products.
What role does the phosphate group play in the sodium-potassium pump?
Hydrolysis of ATP transfers a phosphate group to the Na+/K+ pump, causing a conformational change that allows sodium to be released outside the cell.
What happens to acetyl CoA after its formation?
Acetyl CoA enters the Krebs cycle, where it contributes to energy production, and can also be converted into fats during lipogenesis.
How does the body utilize glycerol from lipolysis?
Glycerol from lipolysis can enter the glycolysis pathway, where it is used for energy production.
In what situation is protein used as a main energy source?
Protein is primarily used as an energy source during extreme starvation when carbohydrate and fat stores are depleted.
What is the end product of anaerobic glycolysis?
The end product of anaerobic glycolysis is lactate, which can be converted back to glucose in the liver.
What triggers glycogenolysis in the body?
Glycogenolysis is triggered by glucagon, which signals the body to break down glycogen into glucose when blood sugar levels are low.
What happens during beta oxidation of fatty acids?
During beta oxidation, fatty acids are broken down in the mitochondria to produce acetyl CoA, which can then enter the Krebs cycle for energy production.
How does calcium influence muscle contraction?
Calcium is essential for muscle contraction as it binds to proteins that initiate the sliding of actin and myosin filaments, facilitating crossbridge formation.
What is the relationship between ATP and ADP?
ATP is broken down to ADP (adenosine diphosphate) and inorganic phosphate (Pi) during energy release, which can be rephosphorylated to regenerate ATP.
