Praxis 5905 Science Questions and
Answers Latest Version Already Passed
What is the process of photosynthesis?
✔✔ Photosynthesis is the process by which plants convert sunlight, water, and carbon dioxide
into glucose and oxygen.
Explain the difference between a physical change and a chemical change.
✔✔ A physical change alters the form or appearance of a substance without changing its
chemical composition, while a chemical change results in the formation of new substances.
What role do mitochondria play in a cell?
✔✔ Mitochondria are the powerhouse of the cell, producing energy through cellular respiration.
Describe the water cycle and its main stages.
✔✔ The water cycle includes evaporation, condensation, precipitation, and collection, which
continuously moves water through the environment.
What is Newton’s first law of motion?
1
,✔✔ An object at rest stays at rest, and an object in motion stays in motion unless acted upon by
an external force.
How does DNA function in living organisms?
✔✔ DNA stores genetic information that guides the development, functioning, and reproduction
of organisms.
What causes seasons on Earth?
✔✔ Seasons are caused by Earth’s tilt on its axis and its orbit around the Sun, leading to varying
sunlight angles and day lengths.
Explain the difference between renewable and nonrenewable energy sources.
✔✔ Renewable energy sources can be replenished naturally, such as solar or wind energy, while
nonrenewable sources like fossil fuels are finite.
What is an ecosystem?
✔✔ An ecosystem is a community of living organisms interacting with each other and their
physical environment.
2
,How do enzymes affect chemical reactions in the body?
✔✔ Enzymes act as catalysts that speed up chemical reactions without being consumed.
What is the difference between a conductor and an insulator?
✔✔ Conductors allow electricity or heat to pass through easily, while insulators resist the flow.
Describe the structure of an atom.
✔✔ An atom consists of a nucleus containing protons and neutrons, with electrons orbiting
around it.
What is the principle of conservation of mass?
✔✔ Mass cannot be created or destroyed in a closed system during chemical reactions.
What causes tides in the ocean?
✔✔ Tides are caused primarily by the gravitational pull of the Moon and Sun on Earth’s oceans.
How does natural selection drive evolution?
3
, ✔✔ Natural selection favors organisms with advantageous traits that increase survival and
reproduction, leading to evolutionary change over time.
What is the difference between velocity and acceleration?
✔✔ Velocity is the speed and direction of an object’s movement; acceleration is the rate of
change of velocity.
Explain how vaccines help protect against disease.
✔✔ Vaccines stimulate the immune system to recognize and fight specific pathogens without
causing the disease.
What is the function of chlorophyll in plants?
✔✔ Chlorophyll absorbs light energy needed for photosynthesis.
Describe the difference between a prokaryotic and eukaryotic cell.
✔✔ Prokaryotic cells lack a nucleus and membrane-bound organelles; eukaryotic cells have
both.
What is the significance of the periodic table?
4
Answers Latest Version Already Passed
What is the process of photosynthesis?
✔✔ Photosynthesis is the process by which plants convert sunlight, water, and carbon dioxide
into glucose and oxygen.
Explain the difference between a physical change and a chemical change.
✔✔ A physical change alters the form or appearance of a substance without changing its
chemical composition, while a chemical change results in the formation of new substances.
What role do mitochondria play in a cell?
✔✔ Mitochondria are the powerhouse of the cell, producing energy through cellular respiration.
Describe the water cycle and its main stages.
✔✔ The water cycle includes evaporation, condensation, precipitation, and collection, which
continuously moves water through the environment.
What is Newton’s first law of motion?
1
,✔✔ An object at rest stays at rest, and an object in motion stays in motion unless acted upon by
an external force.
How does DNA function in living organisms?
✔✔ DNA stores genetic information that guides the development, functioning, and reproduction
of organisms.
What causes seasons on Earth?
✔✔ Seasons are caused by Earth’s tilt on its axis and its orbit around the Sun, leading to varying
sunlight angles and day lengths.
Explain the difference between renewable and nonrenewable energy sources.
✔✔ Renewable energy sources can be replenished naturally, such as solar or wind energy, while
nonrenewable sources like fossil fuels are finite.
What is an ecosystem?
✔✔ An ecosystem is a community of living organisms interacting with each other and their
physical environment.
2
,How do enzymes affect chemical reactions in the body?
✔✔ Enzymes act as catalysts that speed up chemical reactions without being consumed.
What is the difference between a conductor and an insulator?
✔✔ Conductors allow electricity or heat to pass through easily, while insulators resist the flow.
Describe the structure of an atom.
✔✔ An atom consists of a nucleus containing protons and neutrons, with electrons orbiting
around it.
What is the principle of conservation of mass?
✔✔ Mass cannot be created or destroyed in a closed system during chemical reactions.
What causes tides in the ocean?
✔✔ Tides are caused primarily by the gravitational pull of the Moon and Sun on Earth’s oceans.
How does natural selection drive evolution?
3
, ✔✔ Natural selection favors organisms with advantageous traits that increase survival and
reproduction, leading to evolutionary change over time.
What is the difference between velocity and acceleration?
✔✔ Velocity is the speed and direction of an object’s movement; acceleration is the rate of
change of velocity.
Explain how vaccines help protect against disease.
✔✔ Vaccines stimulate the immune system to recognize and fight specific pathogens without
causing the disease.
What is the function of chlorophyll in plants?
✔✔ Chlorophyll absorbs light energy needed for photosynthesis.
Describe the difference between a prokaryotic and eukaryotic cell.
✔✔ Prokaryotic cells lack a nucleus and membrane-bound organelles; eukaryotic cells have
both.
What is the significance of the periodic table?
4
