Science 6 Flashcards
What is the primary function of red blood cells in the human body?
The primary function of red blood cells is to transport oxygen from the lungs to the body’s tissues and to carry carbon dioxide back to the lungs to be exhaled.
Define ‘inertia’.
Inertia is the resistance of any physical object to any change in its velocity, including changes to the object’s speed or direction of motion.
What is a light year and what does it measure?
A light year is a unit of astronomical distance equivalent to the distance that light travels in one year, which is approximately 5.88 trillion miles (9.46 trillion kilometers).
How is sound produced and transmitted?
Sound is produced by vibrating objects and is transmitted through a medium (like air, water, or solids) as a wave of pressure variations.
What is the difference between a comet, an asteroid, and a meteor?
A comet is a small, icy celestial body that, when passing close to the Sun, heats up and begins to release gases. An asteroid is a small rocky body orbiting the Sun, mostly found in the asteroid belt between Mars and Jupiter. A meteor is the flash of light (a “shooting star”) that we see in the sky when a small piece of space debris burns up as it enters the Earth’s atmosphere.
Describe the water cycle.
The water cycle describes the continuous movement of water on, above, and below the surface of the Earth, including processes like evaporation, condensation, precipitation, and runoff.
What is Newton’s Third Law of Motion?
Newton’s Third Law of Motion states that for every action, there is an equal and opposite reaction.
What causes tides in the Earth’s oceans?
Tides in Earth’s oceans are caused primarily by the gravitational pull of the moon and, to a lesser extent, the sun.
Name the three layers of the Earth.
The three layers of the Earth are the crust, the mantle, and the core.
What is genetic engineering?
Genetic engineering is the direct manipulation of an organism’s genes using biotechnology, including the editing or altering of DNA sequences.
Explain the basic principle of a lever.
A lever is a simple machine that consists of a rigid bar resting on a pivot point (fulcrum); it works by applying force on one end to lift or move an object at the other end.
What is the pH scale used to measure?
The pH scale measures how acidic or basic a substance is, on a scale of 0 to 14. A pH of 7 is neutral, below 7 is acidic, and above 7 is basic or alkaline.
Describe the process of nuclear fission.
Nuclear fission is a process in which the nucleus of an atom splits into smaller parts, releasing a large amount of energy.
What are antibodies and what is their function in the immune system?
Antibodies are proteins produced by the immune system to help fight infections. They identify and neutralize foreign objects like bacteria and viruses.
Explain the concept of osmosis.
Osmosis is the movement of water molecules through a semi-permeable membrane from a region of lower solute concentration to a region of higher solute concentration.
