Machines
What is energy?
The term to describe the ability to do work, cause movement, or create change in a system.
What is the function of the nucleus in an animal cell?
The nucleus controls the activities of the cell and contains the cell’s DNA.
What is a disease?
A disease is a condition that affects the normal functioning of the body or mind and may cause harm to health.
What is an ecosystem?
An ecosystem is a community of living organisms interacting with each other and their physical environment.
What are some physical properties of metals?
Metals are usually shiny, conductive, malleable, ductile, and have high melting points.
What is chemical energy, which is stored in chemical bonds?
The energy stored in food, batteries, fuels, and other substances because of chemical bonds is called this.
What is the difference between prokaryotic and eukaryotic cells?
Eukaryotic cells contain a nucleus and membrane-bound organelles, while prokaryotic cells do not.
What is the difference between communicable and non-communicable diseases?
Communicable diseases can spread from one organism to another, while non-communicable diseases cannot spread between people.
Why is plastic pollution harmful to ecosystems?
Plastic pollution disrupts ecosystems by harming organisms, damaging habitats, and affecting food chains.
What is the difference between metals, non-metals, and metalloids?
Metals are usually shiny, conductive, and malleable, non-metals are poor conductors and often brittle, while metalloids have properties of both metals and non-metals.
What is Work = Force X Distance, showing energy transferred by movement?
This equation is used to calculate the amount of work done when a force moves an object over a distance.
W=Fd
What does amylase do in the digestive system?
Amylase is an enzyme that breaks down starch into simpler sugars.
What is the difference between acute and chronic diseases?
Acute diseases develop quickly and last a short time, while chronic diseases develop slowly and last for a long period.
Why are single-use plastics a major environmental problem?
Single-use plastics are often discarded after one use and can remain in the environment for hundreds of years.
What is the reactivity series?
The reactivity series is a list of metals arranged from most reactive to least reactive.
What is the law of conservation of energy, stating energy only changes form?
Energy can change forms but cannot be created from nothing or completely destroyed.
Why is the circulatory system important during exercise?
The circulatory system delivers more oxygen and nutrients to muscles during exercise and removes waste products more quickly.
What is a vector in disease transmission?
A vector is an organism, such as a mosquito, that carries and spreads pathogens between organisms.
How can plastics enter the human food chain?
Humans may consume plastics indirectly by eating seafood contaminated with microplastics.
Write the word equation for sodium reacting with water.
Sodium + water → sodium hydroxide + hydrogen
Explain why real-world machines can never be 100% efficient.
Some energy is always transferred to the surroundings as unwanted heat or sound energy during operation.
What is the function of the left ventricle?
The left ventricle pumps oxygenated blood around the body at high pressure.
What are risk factors for non-communicable diseases?
Risk factors include unhealthy diet, lack of exercise, smoking, stress, and genetic factors.
Why is scale important in solving ocean plastic pollution?
Large-scale solutions are needed because plastic pollution affects oceans and ecosystems worldwide.
Why are Group 1 metals highly reactive?
Group 1 metals are highly reactive because they only have one outer electron, which is easily lost.