questions

The formulas for free energy:

·       ΔG is free energy change

·       Formula for free energy change is ΔG = ΔH - TΔS

·       Negative - ΔG: Spontaneous reaction, exergonic

·       Positive + ΔG: Non-spontaneous reaction, endergonic

Cellular respiration and photosynthesis formula:

Photosynthesis occurs in the chloroplasts of plant cells converting light energy from the sun to chemical energy/glucose in the leaves of a tree.

Photosynthesis formula: CO₂ + H₂O + light energy _———> C₆H₁₂O₆ + O₂

(Carbon dioxide + water + light energy = glucose + oxygen)

(substrates/reactants) —→ (products)

Cellular respiration occurs in the mitochondria, converting chemical energy (glucose) to cellular energy (ATP).

  Cellular respiration formula: C₆H₁₂O₆ + O_{2 ———>} CO₂ + H₂O + ATP

glucose + oxygen = Carbon dioxide + water + cellular energy (ATP)

(substrates/reactants) —→ (products)

ATP Synthase - the part that pumps hydrogen protons across the membrane, turning ADP to ATP.

electron transport chain and chemiosmosis are one reaction just the two steps

biochemical pathways:

Glycolysis

• Occurs in cytoplasm, whether or not O₂ is present!!! Breaks glucose into pyruvate.

• Substrates: Glucose and ATP

• Products: 2 Pyruvate, 2 NADH, 2 ATP and H₂O

• Energy Investment: Uses 2 ATP.

• Energy Payoff: Net gain = 2 ATP. Produces 4 ATP, 2 NADH, and 2 pyruvate.

2. Pyruvate Oxidation

• Occurs in mitochondria in eukaryotic cells (only can occur with O₂/oxygen present).

• Converts/oxidizes pyruvate by releasing CO₂ and producing NADH then adding Coenzyme A to make → Acetyl CoA.

  • Substrates: pyruvate and Coenzyme A.

  • Products: CO₂, NADH and Acetyl CoA.

3. Citric Acid Cycle aka Krebs Cycle

• Occurs in mitochondria - completes the breakdown of pyruvate to CO_2. Only can occur with oxygen!

• Process is as follows:

  • Oxaloacetate and acetyl-CoA combine to form Citrate.

  • Decomposing/oxidizing citrate back to oxaloacetate to continue the cycle.

  • As a result, oxidation reactions generate NADH and FADH₂.

• The substrate is Acetyl CoA.

• Products are ATP, CO₂, NADH, and FADH₂.

4. Oxidative Phosphorylation (90% of ATP Production) - all stages

• Electron Transport Chain (ETC):

  • Located in the inner mitochondrial membrane, it can only occur with oxygen.

  • Electrons from NADH reduces Complex I and FADH₂ reduces Complex II move through protein complexes, donating electrons to the Electron Transport Chain (ETC).

  • The final electron acceptor is O₂, forming H₂O.

• Chemiosmosis:

  • H⁺ ions are pumped into the inner membrane during the chain, creating a gradient (proton-motive force).

  • H⁺ flows back to the outer membrane via facilitated diffusion via the protein ATP synthase, generating ATP.

Total ATP yield:

• Glycolysis: ~2 ATP

• Krebs Cycle: ~2 ATP

• Oxidative Phosphorylation: ~26-28 ATP

• Total ATP per glucose: ~32 ATP

6 Enzyme/Electron Carriers of ETC/Chemiosis: in order

1.     NADH dehydrogenase

2.     Succinate dehydrogenase

3.     Q Enzyme -ubiquinone

4.     Cytochrome bc₁ complex

5.     Cytochrome C

6.     Cytochrome c oxidase

·  Cellular Respiration Electron Carriers

·       NADH is produced in glycolysis, pyruvate oxidation and krebs cycle.

·       FADH₂ is produced during the Krebs cycle only, FADH2 serves as an electron carrier that donates electrons to the electron transport chain.

-       1. Answer: photosynthesis

-       What is the gross ATP  of gycolysis = 4

-       Bonus: why wearing darker clothes make you warmer? Because energy is being absorbed.

2 forms of energy: kinetic energy, Potential energy

3 types of energy: chemical, thermal, mechanical

Differences between autotrophs and heterotrophs.

• Autotrophs: Organisms that produce their own food using light or chemical energy (e.g., plants through photosynthesis).

• Heterotrophs: Organisms that obtain food by consuming other organisms (e.g., animals that eat plants or other animals).

Autotrophs (plants, bacteria) produce their own food.

photosynthesis

htereotraphs (animals, humans) cannot produce their own food

repy on autotrophs for energy

1. NADPH is a product of which of the following reactions?

            Light dependant reactions

2. Which isnt part of the Calvin cycle?

            H2O

3. This protein functions by oxidizing H2O

Photosystem 2

4. Of the colors below which has the shortest wavelength?

Indigo, red, green, yellow

5. Competitive inhibitors bind to?

   Active site of the enzyme

6. Which of these would be considered an endergonic reaction?

A reactant is when the products have a higher energy level than the substrates.

7. true or false: Feedback inhibition is when the substrates of a chemical reaction bind to the starting enzyme.

   False

8. Which would not affect the reaction rate of an enzyme?

Amount of enzyme, temp, ph, substrate concentration

9. The stroma is the location of gas exchange in leaves? False

10. Which is not found in the Krebs cycle?

Regeberation of RuBP, o

11. How many protiens pump hydrogem protons out of the matrix? 3

12. Where does the cxalvin cycle take place?

Stroma of the chloroplast

13.Which is not a product of the light-dependent reactions?

NADH

14. CARBON FIXATION HAPPENS

Mitochondria, Calvin cycle, Krebs cycle, chemiosmosis

15. Which color has the highest energy level?

Red, blue, indigo, violet

16. Pigments in plants : chlorophyll a, carotenoid, chlorophyll b, eumelanin

17. Opening of a leaf where gas is exchanged: stromata

Aerobic final electron acceptor: oxygen

Anaerobic – sulfur, iron