1. The sun is the source of energy in food through photosynthesis.
2. Leaves turn red in fall due to chlorophyll breakdown.
3. The Calvin cycle is the light-independent step in the stroma.
4. Original energy for photosynthesis is from sunlight.
5. Cellular respiration is modeled by C6H12O6 + 6O2 → 6H2O + 6CO2 + Energy.
6. Lactic acid fermentation: Pyruvic acid + NADH → Lactic acid + NAD+.
7. Citric acid forms in Krebs cycle by acetyl-CoA and oxaloacetic acid.
8. Sugar provides energy for glycolysis.
9. Carbon dioxide is released in the Krebs cycle.
10. Carbon dioxide is a reactant in cellular respiration.
11. Six O2 molecules are required for cellular respiration.
12. Endotherms can't insulate and control temperature involuntarily.
13. Shivering uses ATP to raise body temperature.
14. Gram staining visualizes bacterial antibiotic resistance.
15. Most protists respire with oxygen.
1. **Original Source of Energy in Food:**
The original source of energy in the food we eat is the sun. Through the process of photosynthesis, plants harness solar energy and convert it into chemical energy stored in sugars, which then becomes a source of energy for organisms in the food chain.
2. **Why Leaves are Red in Fall:**
Leaves turn red in the fall because chlorophyll, the green pigment responsible for photosynthesis, breaks down. As sunlight decreases, chlorophyll is no longer actively produced, and other pigments like anthocyanins become more prominent, giving leaves their red color.
3. **True Statement about the Calvin Cycle:**
The correct statement is that the Calvin cycle is the light-independent step of photosynthesis and occurs in the stroma, not the thylakoid membrane.
4. **Original Energy for Photosynthesis:**
The original energy for photosynthesis comes from light. Light energy is absorbed by chlorophyll in the chloroplasts of plant cells and is utilized to convert carbon dioxide and water into glucose.
5. **Equation Modeling Cellular Respiration:**
The equation that best models cellular respiration is: C6H12O6 + 6O2 → 6H2O + 6CO2 + Energy. This represents the breakdown of glucose in the presence of oxygen to produce carbon dioxide, water, and energy.
6. **Lactic Acid Fermentation Equation:**
Lactic acid fermentation can be modeled by the equation: Pyruvic acid + NADH → Lactic acid + NAD+. This process occurs in the absence of oxygen and helps regenerate NAD+ for glycolysis.
7. **Formation of Citric Acid in Krebs Cycle:**
Citric acid is formed in the Krebs cycle when acetyl-CoA joins with a large molecule called oxaloacetic acid.
8. **Macromolecule Providing Energy for Glycolysis:**
The macromolecule providing the energy that starts glycolysis is sugar (glucose).
9. **Release of Carbon Dioxide in Cellular Respiration:**
Carbon dioxide is released during the Krebs cycle in cellular respiration.
10. **Reactant in Cellular Respiration:**
Carbon dioxide is a reactant in cellular respiration.
11. **O2 Molecules Required for Cellular Respiration:**
Six O2 molecules are required for two glucose molecules to undergo cellular respiration.
12. **True Statement about Thermoregulation:**
The correct statement is that endotherms cannot insulate their bodies and can only control their body temperature involuntarily.
13. **ATP Utilization to Raise Body Temperature:**
Shivering is an activity that uses ATP to raise body temperature.
14. **Use of Gram Staining in Bacterial Response:**
Gram staining can be used to visualize bacterial antibiotic resistance, providing insights into their response to environments.
15. **Protists' Respiration with Oxygen:**
The correct statement is that most protists only respire with oxygen.