10.1 photosynthesis uses light to make carbohydrates

Question 1

Photosynthesis

Answer 1

Process where sunlight is harnessed to convert carbon dioxide (CO2) and water (H2O) into glucose (C6H12O6) and oxygen (O2).

Question 2

Autotrophs vs. Heterotrophs

Answer 2

Autotrophs: Organisms capable of photosynthesis, such as plants, algae, and cyanobacteria. Heterotrophs: Organisms unable to photosynthesize, relying on consuming other organisms for food, e.g., animals, fungi, and most bacteria.

Question 3

Redox Process

Answer 3

Oxygen atoms in water (H2O) are reduced to oxygen gas (O2), while carbon atoms in carbon dioxide (CO2) are oxidized to form carbohydrate molecules (sugars).

Question 4

Non-oxygenic Photosynthesis

Answer 4

Some organisms perform photosynthesis without producing oxygen. Purple sulfur bacteria utilize hydrogen sulfide (H2S), while green sulfur bacteria use sulfide ions, hydrogen, and ferrous iron as electron donors.

Question 5

Two Photosynthesis Pathways

Answer 5

-Light Reaction: Takes place in the thylakoid membrane, converting light energy into chemical energy in the form of adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH).
-Carbon-fixation Reaction: Occurs in the stroma of chloroplasts, utilizing ATP, NADPH, and carbon dioxide (CO2) to synthesize carbohydrates (e.g., glucose).