A1.2 Nucleic Acid SL

What is the primary pigment involved in photosynthesis?

• Chlorophyll
• Carotene
• Xanthophyll
• Phycobilin

Answer explanation

Chlorophyll is the primary pigment involved in photosynthesis, responsible for absorbing light energy. Carotene, xanthophyll, and phycobilin are accessory pigments.

Which process directly uses light energy to split water molecules?

• Photolysis
• Glycolysis
• Calvin cycle
• Chemiosmosis

Answer explanation

Photolysis uses light energy to split water molecules, producing oxygen, protons, and electrons. Glycolysis, the Calvin cycle, and chemiosmosis do not involve splitting water molecules.

Fill in the blank: The waste product of photosynthesis is _____.

Answer explanation

Oxygen is the waste product of photosynthesis, released during the photolysis of water.

What is the main purpose of chromatography in photosynthesis studies?

• To separate and identify pigments
• To measure oxygen production
• To monitor pH levels
• To count bubbles

Answer explanation

Chromatography is used to separate and identify pigments in photosynthesis studies. Measuring oxygen production, monitoring pH levels, and counting bubbles are different experimental techniques.

Which wavelengths of light are most strongly absorbed by chlorophyll?

• Blue and red
• Green and yellow
• Violet and orange
• Infrared and ultraviolet

Answer explanation

Chlorophyll most strongly absorbs blue and red wavelengths of light. Green and yellow are reflected, giving plants their green color.

How is the rate of photosynthesis commonly measured in experiments?

• Counting oxygen bubbles
• Measuring pH changes
• Using a microburette
• Measuring light intensity

Answer explanation

The rate of photosynthesis is commonly measured by counting oxygen bubbles, measuring pH changes, and using a microburette. Measuring light intensity is not a direct measure of photosynthesis rate.

What happens to the oxygen produced during photosynthesis?

• It diffuses out of the leaf through stomata
• It is used to produce glucose
• It remains in the chloroplast
• It is converted to carbon dioxide

Answer explanation

The oxygen produced during photosynthesis diffuses out of the leaf through stomata. It is not used to produce glucose, does not remain in the chloroplast, and is not converted to carbon dioxide.

Which factors are considered limiting factors in photosynthesis?

• Carbon dioxide concentration
• Light intensity
• Temperature
• Oxygen concentration

Answer explanation

Limiting factors in photosynthesis include carbon dioxide concentration, light intensity, and temperature. Oxygen concentration is not typically considered a limiting factor.

What is the function of photosystems in photosynthesis?

• Absorb light and generate excited electrons
• Split water molecules
• Produce glucose
• Transport oxygen

Answer explanation

Photosystems absorb light and generate excited electrons. They do not directly split water molecules, produce glucose, or transport oxygen.

Fill in the blank: The absorption spectrum of chlorophyll shows the wavelengths of light that are _____.

Answer explanation

The absorption spectrum of chlorophyll shows the wavelengths of light that are absorbed.