Exploring Photosynthesis Concepts in AP Biology

The video covers the second half of the AP Biology Unit 3 review, focusing on cellular energy, photosynthesis, and cellular respiration. It begins with an overview of cellular energy, emphasizing the need for a constant energy input to combat entropy. The video explains energy coupling, highlighting exergonic and endergonic reactions powered by ATP. It then delves into photosynthesis, detailing the light-dependent reactions and the Calvin cycle. The video concludes with a lab experiment on photosynthesis using spinach leaf discs, demonstrating the relationship between light intensity and photosynthesis rate.

What does the second law of thermodynamics state about the universe?

• The universe tends toward increasing entropy.

• The universe remains constant in terms of entropy.

• The universe tends toward decreasing entropy.

• The universe eliminates entropy over time.

What is the primary role of ATP in cellular processes?

• To decrease energy within the cell

• To store energy for long-term use

• To transfer energy for cellular functions

• To create energy from sunlight

What is the significance of ATP hydrolysis in cellular processes?

• It transfers electrons directly to the Calvin cycle.

• It absorbs energy from the surroundings.

• It releases energy to power various cellular activities.

• It builds large molecules from smaller ones.

Which organisms are capable of photosynthesis?

• Only plants

• Plants, some bacteria, and all fungi

• Plants, algae, and some bacteria

• All bacteria and plants

What is the main pigment involved in absorbing light for photosynthesis?

• Carotenoid

• Chlorophyll

• Phycocyanin

• Xanthophyll

What are the main products of the light-dependent reactions in photosynthesis?

• Glucose and oxygen

• Oxygen and carbon dioxide

• ADP and NADP+

• ATP and NADPH

What replaces the electrons in photosystem II during the light-dependent reactions?

• Glucose

• Water

• Carbon dioxide

• Oxygen

Which type of light is best for growing plants, according to the absorption spectrum?

• Only infrared light

• Blue and red light

• Green and yellow light

• Only ultraviolet light

What is the primary function of the Calvin cycle?

• To release oxygen as a by-product

• To fix carbon into sugars

• To produce ATP and NADPH

• To convert light energy to chemical energy

How do light intensity and the presence of carbon sources like bicarbonate affect photosynthesis rates?

• Higher light intensity and bicarbonate presence decrease rates.

• Higher light intensity and bicarbonate presence increase rates.

• Light intensity has no effect; only bicarbonate presence increases rates.

• Both factors have no significant effect on photosynthesis rates.