Question

vi. cellular respiration (1.6)
a. basics
the main purpose of cellular respiration is to make ______.
aerobic respiration requires ______.
anaerobic respiration occurs when no ______ is present.
b. fermentation
alcoholic fermentation produces co₂ and ______.
lactic acid fermentation occurs in ______ cells during exercise.
c. mitochondria
the mitochondria perform ______ respiration.
d. cellular respiration reaction

Explanation:

(for A, B, C sections):

A. Basics

• Step 1: Recall cellular respiration’s goal. Cellular respiration breaks down glucose to generate ATP (energy for cells).
• Step 2: Aerobic respiration uses oxygen (aerobic = “with air”).
• Step 3: Anaerobic respiration is “without air,” so it occurs when oxygen is absent.

B. Fermentation

• Step 1: Alcoholic fermentation (e.g., in yeast) converts pyruvate to $\ce{CO_{2}}$ and ethanol.
• Step 2: Lactic acid fermentation (e.g., in muscle cells during intense exercise) produces lactic acid when oxygen is limited.

C. Mitochondria

• Step 1: Mitochondria are the site of aerobic respiration (Krebs cycle, electron transport chain), which requires oxygen.

Answer:

s:
A. Basics

1. The main purpose of cellular respiration is to make $\boldsymbol{ATP}$ (adenosine triphosphate).
2. Aerobic respiration requires $\boldsymbol{oxygen}$.
3. Anaerobic respiration occurs when no $\boldsymbol{oxygen}$ is present.

B. Fermentation

1. Alcoholic fermentation produces $\ce{CO_{2}}$ and $\boldsymbol{ethanol}$ (or alcohol).
2. Lactic acid fermentation occurs in $\boldsymbol{muscle}$ cells during exercise.

C. Mitochondria
The mitochondria perform $\boldsymbol{aerobic}$ respiration.