Earth A Q3 2025 FINAL EXAM

What is the impact of deforestation on the environment?

• Increased biodiversity and habitat restoration

• Decreased carbon dioxide levels and improved water cycles

• Loss of habitat, decreased biodiversity, increased carbon dioxide levels, and disruption of water cycles

• Enhanced soil fertility and agricultural productivity

What action could increase the amount of oxygen in the air?

• Planting more trees could increase the amount of oxygen in the air.

• Reducing the use of fossil fuels.

• Increasing industrial emissions.

• Using more plastic products.

Define ecosystem.

• A system of government that regulates the economy.

• A community of living organisms interacting with their physical environment, including both biotic and abiotic components.

• A method of farming that uses advanced technology.

• A type of social network that connects individuals.

What impact do seasonal changes have on Yosemite's flora and fauna?

• Seasonal changes have no impact on flora and fauna.

• Seasonal changes bring variations in temperature and precipitation, affecting both flora and fauna.

• Seasonal changes only affect the fauna, not the flora.

• Seasonal changes lead to a decrease in biodiversity.

What do humans and plants depend on for respiration?

• Humans depend on nitrogen, while plants depend on oxygen.

• Humans depend on carbon dioxide, while plants depend on nitrogen.

• Humans depend on oxygen, while plants depend on carbon dioxide.

• Humans depend on hydrogen, while plants depend on oxygen.

What percentage of Earth's history is made up of the Precambrian time?

• 70%

• 80%

• 88%

• 90%

Define photosynthesis.

• Photosynthesis is the process by which green plants use sunlight to synthesize foods with the help of chlorophyll, converting carbon dioxide and water into glucose and oxygen.

• Photosynthesis is the process by which animals convert food into energy using oxygen.

• Photosynthesis is the method by which plants absorb nutrients from the soil and convert them into energy.

• Photosynthesis is the process of breaking down glucose to release energy in the presence of oxygen.

What is the role of the ozone layer?

• It helps in the formation of clouds.

• It protects life on Earth by absorbing the majority of the sun's harmful ultraviolet radiation.

• It regulates the Earth's temperature.

• It provides oxygen for living organisms.

What role do decomposers play in an ecosystem?

• Decomposers break down dead organic matter, returning nutrients to the soil and supporting plant growth.

• Decomposers produce energy through photosynthesis.

• Decomposers compete with plants for sunlight and nutrients.

• Decomposers are primary producers that create food for herbivores.

What is biodiversity?

• The total number of species in a given area.

• The variety of life in a particular habitat or ecosystem, including the diversity of species, genetic variation, and ecosystem diversity.

• The study of how species interact with each other.

• The process of evolution in different species.