Metabolism Flashcards
What appetite related hormones are released in the digestive system to suppress appetite? Other than suppressing hunger, what are their functions?
Cholecystokinin is released in the duodenum in response to chyme entering. It’s function is to stimulate bile and pancreatic enzymes as well as stimulation of the vagus nerve to suppress appetite.
Peptide YY is released before chyme enters the ileum. It is primarily responsible for suppressing hunger.
When we eat food, it is used as a source of energy; we call this source of energy a calorie. However, the amount of energy depends on the nutrient consumed. List the about of energy we should expect from each of the organic molecules/nutrients.
Carbohydrates provide 4 calories/gram consumed
Fats provide 9 calories/gram consumed
Proteins provide 4 calories/gram consumed
Carbohydrates are stored in the liver and muscle tissue in the form of glycogen. Glycogen must be broken down into a simple form (glucose) in order for them to be metabolized. What process takes place in order for glucose to be used as energy?
Carbohydrates are oxidized in 3 ways.
1. Glycolysis (by-product of pyruvic acid)
2. Anaerobic fermentation - the process of oxidizing glucose that does not require oxygen (by-product of lactic acid)
3. Aerobic respiration - the process of oxidizing glucose that requires oxygen (by-product of carbon dioxide and water).
These processes take place in the order listed above. Therefore, a short bout of exercise (e.g., 40 yard dash that last 47 seconds) relies on glycolysis and anaerobic fermentation. A activity that lasts longer than (e.g., a 5k run) relies on aerobic respiration to oxidize glucose.
Basal Metabolic Rate (BMR) measures the amount of energy needed to maintain life. List a few of these functions related to BMR.
Brain function, heart rate, respiration rate, GI function, etc.
Explain the difference between high-density lipoproteins (HDL) and low-density lipoproteins (LDL); include why one is considered better to have in the body than the other.
HDLs and LDLs are present in the body because of the existence of cholesterol in the blood. HDL are considered good because they have a better ability to transport cholesterol to the liver for filtration. LDL are considered “bad” in the blood because they do not transport cholesterol as easily. LDL, therefore, do not remove the cholesterol from the blood causing it to deposit in the arteries of the vascular system. These deposits lead to cardiovascular disease known as arteriosclerosis.
Name the sources that contribute to HDL and LDL.
HDL - flaxseed, sunflower seeds, cashews, peanuts, almonds, and exercise
LDL - saturated fatty foods, cigarette smoking, coffee, and stress
