Metabolism
All the chemical and physical processes involved in maintaining life are referred to as
Carnitine
Shuttles fatty acids from the cytosol into the mitochondria
Acetyl CoA
Ketones are produced from:
Gluconeogenesis
The process whereby the body produces glucose from amino acid and glycerol molecules
Glycolysis
A process involving reactions that convert glucose to pyruvate
Lower BMR
Older males generally have a ______ BMR than younger males
A healthy weight for an individual should not be based exclusively on weight, but on:
Total amount of body fat, location of body fat, and presence or absence of weight-related medical problems
Eating disorders
Refers to a broad category that includes symptoms from both anorexia and bulimia
When the diet contains more energy than is expended, the excess energy:
Is stored as fat in adipose tissue
Underwater weighing assesses body composition based on the principle that:
Lean body tissue is more dense than adipose tissue
The benefits of participating in different types of exercise are:
- Strengthening a variety of muscle groups
- Reducing the chances of injury
- Promoting activities that are more interesting and thus more likely to be continued
Another adaptation that occurs with exercise, besides improvement in fitness is:
Increased bone density
For every pound of weight lost during an athletic event, ________ of water should be consumed during exercise or immediately thereafter.
3 cups
Type 1
Prolonged, low intensity exercise uses mainly ______ muscle fibers.
Proteins:
Supply about 2% to 5%, or at the most 10%, of energy needs for endurance events.
Goal of Glycolysis
Break down carbs to generate energy & Provide building blocks for other compounds
how many 3-carbon compounds are made from a 6-carbon glucose molecule
2
What is the end product of glycolysis?
Pyruvate
Stages of aerobic cellular respiration
1. Glycolysis
2. Transition Reaction
3. Citric Acid Cycle
4. Electron Transport Chain
Anaerobic metabolism occurs when:
Cells do not have a mitochondria
Oxygen is lacking
How is citric acid formed during the citric acid cycle?
Acetyl CoA combines with oxaloacetate
How many NADH + H+ are formed in the citric acid cycle?
3 (oxidation of citrate, alpha ketoglutarate, fumorate)
Why is the citric acid cycle called a cycle?
Series of continuing reactions
What are the end products of the electron transport chain?
Electrons, H+, Oxygen = Water
How does the Cori cycle help muscles continue to work during HIIT?
Lactate generated in muscle transported to liver and converted to glucose, and returned to muscle
How are fatty acids shuttled into the mitochondria for energy production?
Carrier - carnitine
What is the end product of beta-oxidation?
Acetyl-CoA (which enters the citric acid cycle)
NADH + H+ and FADH2
How do fatty acids enter the citric acid cycle?
Cleaved in 2 carbon units to create acetyl CoA, which enters the cycle
What conditions must exist in the body to promote the formation of ketones?
-Incomplete fatty acid oxidation
-Hormonal imbalance
-Inadequate production of glucose (type 1 diabetes, starvation, fasting)
glucogenic amino acids
use carbons to form pyruvate
ketogenic amino acids
use carbons to form acetyl-CoA
In order to use amino acids as a fuel, what must happen to the nitrogen attached to the amino acid?
Deamination - amino group is removed
Where does the nitrogen attached to an amino acid used as fuel end up?
Converted to ammonia by urea cycle and excreted in urea
What part of the amino acid is used in the metabolic pathways?
Carbon skeleton
What is the name of the pathway that converts amino acids to glucose?
Gluconeogenesis
Why can't fat be used to synthesize glucose?
Fatty acids have even number of carbons and are broken down to acetyl CoA
Where does glycolysis take place in a cell?
Cytosol
What factors determine the regulation of glycolysis and citric acid cycle pathways?
ATP and ADP
Enzymes
Hormones
Vitamins
Minerals
How do ATP concentrations regulate metabolism?
High ATP decrease energy production pathways and increase anabolic reactions,
High ADP increase energy production pathways
Energy balance
the relationship between energy intake and energy expenditure
Energy equilibrium
when calories consumed matches the amount of energy expended
Positive energy balance
energy exceeds energy expenditure and results in weight gain
Negative energy balance
energy intake is less than energy expenditure and weight loss occurs
Basal Metabolism (BMR)
- Minimum amount of energy expended to keep body alive
- 60-70% of total energy expenditure
- Heart beat, respiration, other organs
Thermic Effect of Food (TEF)
energy used to digest, absorb, transport, store and metabolize
Thermogenesis
The process of heat production in the body (non-voluntary physical activity)
Direct calorimetry
Measures the change in water temperature to calculate the energy produced by the body
Indirect calorimetry
Measures the expired air while a person exercises
Chain-breaking
separate behaviors that occur together
stimulus control
Altering the environment to minimize the stimuli for eating; for example, removing foods from sight and storing them in kitchen cabinets.
Cognitive restructuring
change frame of mind regarding eating
Contingency management
Prepare for situations that may trigger overeating
Self-monitoring
track food eaten, when, why, how you feel, physical activities, body weight