3.6-7: Cellular Respiration Generally

Question 1

Cells harvest _____ energy stored in ___ molecules and use it to generate ___.

Answer 1

• Chemical
• organic
• ATP

Question 2

What is the cellular respiration reaction?

Answer 2

Organic molecules + oxygen —> CO2 + H2O + energy

C6H12O2 + 6O2 —> 6CO2 + 6H20 + ATP + HEAT

Question 3

What is the major source of fuel for animals? What does it break down into?

Answer 3

• Starch

- glucose

Question 4

One atom of hydrogen has 1 ___ and 1 ____. An ion of hydrogen has 1_____.

Answer 4

• proton
• electron
• proton

Question 5

Movement of protons means movement of __.

Answer 5

H+

Question 6

How does the oxidation of glucose aid in ATP synthesis?

Answer 6

• oxidation of glucose transfer electron to a lower energy state, releasing nrg to be used in ATP synthesis

Question 7

During cellular respiration, most electrons will follow this “downhill” exergonic path. What is this path?

Answer 7

Glucose —> NADH (as a transporter) —> ETC —> oxygen (form h2O)
- Please see flash on goodnotes

Question 8

NADH acts as a transporter, meaning?

Answer 8

It moves electrons to where they are supposed to go

- btw its a coenzyme I think

Question 9

What are the steps of breaking down glucose in order to harvest energy? (4)

Answer 9

1. Each electron taken travels with a proton (H+)
2. Dehydrogenases take 2 electrons and 2 protons from glucose (remove 2 hydrogen atoms) (oxidizing agent for glucose)
3. Tranfers 2 electrons and 1 proton to the coenzyme NAD+, which reduces to NADH that stores the energy
   — other proton is released into surrounding solution as H+
4. NADH carries electron to the electron transport chain

Question 10

Which area of the mitochondria is the electron transport chain?

Answer 10

Cristae

Question 11

What is the electron transport chain?

Answer 11

• A sequence of membrane proteins that shuttle electrons down a series of redox reactions

Question 12

What is a redox reaction?

Answer 12

The sum of reducing and oxidizing reactions

Question 13

Why is the electron transport chain important, in terms of energy, and how? (3)

Answer 13

• releases energy used to make ATP
• ETC transfers electrons to O2, the final electron acceptor to make water
• releases energy

Question 14

What are the three stages of cellular respiration?

Answer 14

1. Glycolysis
2. Pyruvate oxidation (prep rxn) and the citric acid cycle (krebs or tricarboxylic acid cycle)
3. Oxidative phosphorylation (ETC and chemiosmosis)

Question 15

Where does glycolysis occur in the cell?

Answer 15

Cytoplasm

Question 16

Glycolysis is the primitive form of what?

Answer 16

• primitive form of cellular respiration before the evolution of eukaryotes (occurs in all cells)