Combustion
This gas in the air is needed for a fire to keep burning.
What is oxygen?
This process releases energy from food inside living cells.
What is respiration?
This property allows metals to conduct electricity, making them useful for electrical wires.
What is electrical conductivity?
This force pulls objects towards the centre of the Earth.
What is gravity?
This molecule carries the genetic instructions that determine an organism's characteristics.
What is DNA?
These are the two main products formed when a hydrocarbon burns completely in plenty of oxygen.
What are carbon dioxide and water?
This sugar is broken down during aerobic respiration to release energy.
What is glucose?
This metal is commonly used to make drinks cans because it is lightweight and resistant to corrosion.
What is aluminium?
This force acts between two surfaces that rub against each other and slows moving objects down.
What is friction?
These structures in the nucleus contain genes made of DNA.
What are chromosomes?
This type of combustion happens when there is not enough oxygen, producing carbon monoxide or soot instead of only carbon dioxide.
What is incomplete combustion?
These are the three products made during aerobic respiration.
What are carbon dioxide, water, and energy?
This mixture of a metal with one or more other elements is often stronger and harder than the pure metal.
What is an alloy?
This happens to an object when the forces acting on it are balanced.
What is moving at a constant speed (or remaining at rest)?
This scientist proposed the theory of evolution by natural selection after studying living organisms and fossils.
Who is Charles Darwin?
These three things make up the "fire triangle" and are all needed for combustion to occur.
What are heat, fuel, and oxygen?
This type of respiration happens when there is not enough oxygen available, producing lactic acid in human muscles.
What is anaerobic respiration?
Stainless steel is commonly used for cutlery because it has these two important properties.
What are strength and resistance to corrosion (doesn't rust)?
This quantity is calculated by dividing the distance travelled by the time taken.
What is speed?
This process explains how organisms with helpful inherited characteristics are more likely to survive, reproduce, and pass on their genes.
What is natural selection?
A Bunsen burner with the air hole open produces this type of flame because more oxygen is available for combustion.
What is a blue (roaring) flame?
During exercise, this condition occurs when muscles do not receive enough oxygen, causing lactic acid to build up and increasing the need for extra oxygen afterwards.
What is oxygen debt?
Engineers choose different metals for different jobs because they compare properties such as strength, density, conductivity, and this ability to be shaped without breaking.
What is malleability?
A car accelerates because the forward driving force is greater than the opposing forces. The overall force causing this change in motion is called this.
What is the resultant (or net) force?
Over many generations, this can happen to a population as advantageous alleles become more common, making the population better adapted to its environment.
What is evolution?