Chapter 5 Flashcards
What is obesity?
Obesity has been called America’s #1 disease. As of 2020, almost 40% of U.S. adults are obese.
What is the Body Mass Index (BMI) for a healthy individual?
BMI 19-24
What is the BMI range for overweight individuals?
BMI 25-29
At what BMI is a person considered obese?
BMI 30+
What causes obesity?
Obesity occurs over years due to energy imbalance: taking in much more energy than expended.
What does a lowercase ‘calorie’ denote?
The amount of energy required to raise the temperature of 1 g of water by 1 °C.
What do capital ‘Calories’ represent?
Equal to 1000 calories, or 1 kilocalorie (kcal).
What are macromolecules?
Building blocks or subunits found in food, used to make new molecules and as sources of energy.
What is NEAT?
Nonexercise activity thermogenesis, which includes daily activities like yard work, shopping, and walking the dog.
How do NEAT levels affect fat gain?
People who increase their NEAT gain the lowest amount of fat.
What is the relationship between sitting time and calorie burning?
Obese individuals sat 2.25 hours longer; by sitting less, lean people burned +350 Calories per day.
What is cellular respiration?
A series of reactions that converts stored food energy into ATP.
What are the three major stages of cellular respiration?
- Glycolysis * Kreb’s / Citric acid cycle * Electron transport chain
Where does glycolysis occur?
In the cytoplasm.
Does glycolysis require oxygen?
No, glycolysis does not require oxygen.
What is produced in glycolysis?
2 pyruvate and a little bit of ATP.
What happens during the Kreb’s cycle?
Extracts energy from food, CO2 is released, and NAD+ picks up electrons.
Where does the electron transport chain occur?
In the inner membranes of the mitochondria.
What is the role of oxygen in the electron transport chain?
Oxygen accepts electrons and combines with hydrogen atoms to produce water.
What happens when oxygen consumption exceeds oxygen intake?
Aerobic respiration stops, and fermentation occurs.
What are the products of fermentation?
- Lactic acid (in bacteria and humans) * Alcohol (in yeast)
What is the purpose of fermentation?
To regenerate NAD+.
How is glucose broken down in the absence of oxygen?
Through anaerobic fermentation processes.
How do animals store extra energy?
- As glycogen in muscle and liver cells (short-term) * As triglycerides in fat cells (long-term)
