Microbiology and Ecosystem Concepts

This video tutorial by Mrs. Geiss reviews key eighth-grade science topics in preparation for the EOG. It covers properties of matter, energy concepts, the hydrosphere, Earth's history, biotechnology, health and disease, and ecosystems. Each section provides a detailed overview of the subject matter, including atoms, chemical reactions, energy conservation, water cycles, fossils, DNA, and ecosystem dynamics. The tutorial emphasizes understanding and applying scientific principles to real-world scenarios, preparing students for their upcoming exams.

What is the smallest unit of an element that retains the properties of that element?

• Molecule

• Atom

• Compound

• Mixture

Which of the following is a chemical change indicator?

• Freezing

• Color change

• Boiling

• Melting

What is the main difference between renewable and non-renewable energy sources?

• Non-renewable energy can be replenished quickly

• Renewable energy is more expensive

• Non-renewable energy causes no pollution

• Renewable energy can be replenished naturally

Which process in the water cycle involves water vapor turning into liquid water?

• Precipitation

• Evaporation

• Condensation

• Transpiration

What is the primary role of algae in marine ecosystems?

• They are top predators

• They are secondary consumers

• They are primary producers

• They decompose organic matter

What does the law of superposition state about rock layers?

• Older rocks are found above younger rocks

• Younger rocks are found above older rocks

• All rock layers are the same age

• Rock layers are formed by volcanic activity

Which of the following is an example of a homologous structure?

• Wings of a bat and a butterfly

• Leaves of a tree and a cactus

• Fins of a fish and a whale

• Legs of a human and a dog

What is the primary function of DNA in living organisms?

• To provide energy

• To store genetic information

• To protect against diseases

• To transport nutrients

Which of the following is a non-living microbe capable of replicating inside a host?

• Bacteria

• Protozoa

• Virus

• Fungi

What is the role of decomposers in an ecosystem?

• They produce energy from sunlight

• They consume other organisms

• They break down dead material

• They compete for resources