Understanding Primary Productivity

Mr. Smeeds covers primary productivity, explaining how solar energy is transformed by organisms. The video details the measurement of productivity, using kilocalories per meter squared per year, and introduces concepts like gross and net primary productivity. It discusses ecological efficiency, noting that only a small percentage of sunlight is converted into biomass. The video highlights trends in productivity, linking higher productivity to greater biodiversity, and examines factors affecting productivity in different biomes. Practice questions are provided to reinforce learning.

What is the primary unit used to measure primary productivity?

• Joules per second

• Calories per gram

• Watts per square meter

• Kilocalories per meter squared per year

How does higher primary productivity affect biodiversity in an ecosystem?

• It only affects plant species

• It decreases biodiversity

• It has no effect on biodiversity

• It increases biodiversity

What does net primary productivity represent?

• Total energy lost to the environment

• Energy used for cellular respiration

• Energy stored as biomass after respiration

• Total sunlight captured by plants

Which of the following is true about gross primary productivity?

• It is the energy available to consumers

• It is the energy lost during respiration

• It is the energy stored as biomass

• It is the total energy captured by plants

What percentage of sunlight is typically captured by plants for photosynthesis?

• 1%

• 50%

• 25%

• 10%

What is the relationship between ecological efficiency and net primary productivity?

• Ecological efficiency is the energy lost during respiration

• Ecological efficiency is the total energy captured by plants

• Ecological efficiency determines the amount of energy stored as biomass

• Ecological efficiency is unrelated to net primary productivity

Which factor does NOT contribute to high net primary productivity in a biome?

• Warm temperatures

• High nutrient availability

• High water availability

• Low temperature

Which biome is likely to have the highest primary productivity?

• Open ocean

• Desert

• Tundra

• Tropical rainforest

Why does the open ocean have low primary productivity?

• Abundance of nutrients

• Lack of sunlight

• Deficiency of nutrients

• Excessive plant growth

Which of the following biomes is characterized by low nutrient availability?

• Swamps and marshes

• Coral reefs

• Tropical rainforests

• Deserts