Unit 1
A disturbance removes most producers in an ecosystem. Predict the first major impact on energy flow. (CED Page #44)
Energy entering the food web decreases, reducing energy available to all higher trophic levels.
Explain why biodiversity increases ecosystem resilience. (CED Page #60)
More species means more functional redundancy, so ecosystems can better withstand disturbances.
Why do populations in early succession grow quickly? (CED Page #72)
Abundant resources and low competition allow rapid population increase.
What drives plate tectonic movement? (CED Page #88)
Convection currents in Earth’s mantle.
Why are renewable energy sources considered sustainable? (CED Page #128)
They replenish naturally on human timescales.
Explain why energy transfer between trophic levels is inefficient. (CED Page #46)
Energy is lost as heat through respiration and metabolic processes.
How do ecosystem services directly support human populations?(CED Page #61)
They provide resources like food, water purification, pollination, and climate regulation.
What characterizes r-selected species? (CED Page #73)
High reproduction rate, low parental care, and rapid maturity.
How does the atmosphere regulate Earth’s temperature? (CED Page #91)
It traps heat through greenhouse gases.
Why does burning fossil fuels increase atmospheric CO₂? (CED Page #132)
Combustion releases stored carbon into the atmosphere.
How does nitrogen become available to plants? (CED Page #48)
Through nitrogen fixation and nitrification by bacteria converting atmospheric nitrogen into usable forms.
Why do islands closer to mainland generally have higher species diversity?(CED Page #62)
Higher immigration rates from nearby mainland populations.
What happens when a population exceeds carrying capacity? (CED Page #76)
Increased competition leads to higher death rates and population decline.
Why does deforestation increase flooding risk?(CED Page #93)
Reduced infiltration and increased surface runoff.
What is one major risk of nuclear energy?(CED Page #133)
Radioactive waste storage and potential accidents.
Explain why primary productivity is higher in tropical regions than in tundra ecosystems. (CED Page #51)
Tropical regions have more sunlight, warmer temperatures, and longer growing seasons.
Describe the difference between primary and secondary succession.(CED Page #66)
Primary succession starts with no soil; secondary succession occurs where soil already exists.
Explain exponential population growth in human systems. (CED Page #77)
Growth increases rapidly when resources are abundant and limiting factors are minimal.
What role does soil play in ecosystems? (CED Page #90)
It stores nutrients and supports plant growth.
Why is energy efficiency important in power systems? (CED Page #136)
It reduces waste heat and resource consumption.
A food web has 50,000 kcal at producer level. Calculate energy available to secondary consumers. (CED Page #53)
50000 x 10% x 10% = 500 kcal
A habitat loses 90 species out of 300. What is percent loss? (CED Page #63)
90/300 x 100 = 30% loss
A population grows from 2,000 to 2,600. Find percent growth. (CED Page #77)
(2600-2000 / 2000) x 100 = 30% growth
A region receives 180 cm precipitation. 65 cm becomes runoff. What remains? (CED Page #93)
180-65 = 115 cm
A system uses 3,000 J of energy at 30% efficiency. How much is useful output?(CED Page#141)
3000 x 30% = 900 J