Photosynthesis and Ecosystem Dynamics

The video covers cellular energetics, focusing on photosynthesis and cellular respiration. It reviews key concepts from AP Biology Unit 3, including enzyme function and energy requirements of living systems. An experiment with radish seeds illustrates the effects of light and water on plant biomass. The video also discusses animal metabolism, energy flow in ecosystems, and the global carbon cycle, highlighting human impact on carbon dioxide levels and climate change.

Which of the following is NOT one of the four big ideas emphasized in AP Biology?

• Energetics

• Systems Interaction

• Evolution

• Photosynthesis

What is the primary source of energy for photosynthesis?

• Sunlight

• Oxygen

• Carbon Dioxide

• Water

In the radish seed experiment, what were the independent variables?

• Biomass and Light

• Water and Biomass

• Temperature and Light

• Light and Water

Why did the radish seeds in the dark lose biomass?

• They used stored energy for growth

• They performed photosynthesis

• They did not receive water

• They absorbed too much light

What do animals rely on for cellular respiration since they cannot perform photosynthesis?

• Stored starch

• Chloroplasts

• Direct sunlight

• Consumed food

How do animals primarily gain weight?

• By consuming more calories than they burn

• By performing photosynthesis

• By absorbing sunlight

• By breathing in more oxygen

What is the term for the total amount of photosynthesis occurring in an ecosystem?

• Net Primary Productivity

• Gross Primary Productivity

• Photosynthetic Rate

• Ecosystem Efficiency

What is the primary cause of the increase in atmospheric carbon dioxide?

• Natural seasonal fluctuations

• Increased photosynthesis

• Decreased respiration

• Human activities like burning fossil fuels

What is the Keeling Curve used to measure?

• Oxygen production

• Carbon dioxide levels in the atmosphere

• Global temperature changes

• Photosynthesis rates

What is a significant effect of increased carbon dioxide levels on the planet?

• Decreased sea levels

• Increased plant growth

• Global warming

• Reduced storm intensity