Cellular Respiration - BIO103

Comprehensive practice questions covering the mechanics, stages, and outputs of cellular respiration as presented by Dr. Hannah Chu.

How are biological reactions classified based on the lecture notes?

Dehydration and hydrolysis, phosphorylation ($-PO_4$), carboxylation ($-COOH$), and oxidation/reduction.

What is the mnemonic for REDOX reactions provided in the notes?

OIL RIG: Oxidation Is Loss of $e^-$, Reduction Is Gain of $e^-$.

What role does the hydride ion ($H^-$) play in cellular respiration?

It acts as an electron carrier to help pass electrons in redox reactions.

What role does the proton ($H^+$) play in cellular respiration?

It is used to generate electrochemical gradients.

What is the chemical equation for cellular respiration?

$$C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{energy}$$

What is the Gibbs free energy ($\Delta G$) value for cellular respiration?

$$-686\,kcal/mol$$

What are the three major steps of cellular respiration?

1 Glycolysis, 2 Krebs cycle, and 3 oxidative phosphorylation.

Where in the cell does Glycolysis occur?

In the cytoplasm.

Which cellular compartment must arsenic enter to cause inhibition of pyruvate oxidation and the Citric acid cycle?

The mitochondrial matrix.

What is the 'net' ATP yield of Glycolysis?

$$2\,ATP$$

What occurs during pyruvate decarboxylation (the 'shunt' step)?

Two $3C$ pyruvates are converted into two $2C\,Acetyl-CoA$ and $2\,CO_2$, yielding $2\,NADH$.

What is the purpose of the Krebs cycle?

To completely oxidize pyruvate and remove high-energy electrons to generate many electron carriers (NADH and FADH2).

What are the two sub-steps of oxidative phosphorylation?

3a Electron transport chain (ETC) and 3b chemiosmosis.

How many electrons does the electron carrier NAD+ accept?

$2$ high energy electrons (carried by $2H$).

What is the theoretical total net ATP yield of respiration in eukaryotes?

$$30\,ATP$$

What is the role of oxygen ($O_2$) in aerobic respiration?

It is the final acceptor of electrons.

What is the primary goal of fermentation (anaerobic respiration)?

To regenerate $NAD^+$ so that glycolysis can continue to produce some ATP.

What are the products of alcoholic fermentation in yeast?

Ethanol and $CO_2$.

What product is generated by lactic acid fermentation in animal cells?

Lactate (lactic acid).