Lecture Notes Review: Light, Diet and Growth, Chemical Reactions, and Magnetism

Flashcards covering light science (rainbows and colours), space (galaxies and asteroids), human biology (nutrients, health, and movement), and basic chemistry and magnetism concepts.

Dispersion

The process of splitting white light into its different colours.

Prism

A solid shape, such as a triangular glass block, used to cause the dispersion of white light.

Spectrum

The range of seven colours seen in white light: red, orange, yellow, green, blue, indigo, and violet.

Primary colours of light

Red, green, and blue, which are the three colours from which all other colours of light can be made.

Cyan

The colour of light produced when blue and green light overlap.

Magenta

The colour of light produced when red and blue light overlap.

Non-luminous

A term describing an object that does not emit its own light, such as a flower seen by reflected light.

Transmit

When light passes through a transparent material, such as a coloured filter.

Galaxy

A system made from stellar dust, gas, stars, and solar systems held together by gravity.

Spiral galaxy

The specific shape of the Milky Way galaxy.

Universe

A term used to describe all of space and everything in it.

Stellar dust

The dust particles found in space that contribute to the mass of a galaxy.

Speed of light

The speed at which light travels, estimated at $300\,000\,km/s$.

Asteroids

Objects made from rock that orbit the Sun, ranging in size from $2\,m$ to nearly $1000\,km$ across.

Asteroid belt

The region of the Solar System between the orbits of Mars and Jupiter where most asteroids are found.

Ceres

The largest known asteroid, discovered in the year $1801$, which has a diameter of $975\,km$.

Starch

A type of carbohydrate used as fuel for respiration after the body breaks it down into glucose.

Protein

A nutrient found in foods like chicken and beans that is essential for making new cells for growth and repair.

Vitamin A

A nutrient needed to help the eyes work well, particularly for vision in dark conditions.

Scurvy

An illness characterized by weak, bleeding gums, caused by a lack of Vitamin C.

Vitamin D

A nutrient needed for strong bones and teeth, often made in the skin when sunlight falls on it.

Rickets

An illness in children caused by a lack of Vitamin D that prevents bones from growing normally.

Anaemia

An illness that causes tiredness due to a lack of iron, resulting in low haemoglobin levels.

Balanced diet

A diet that provides all the different kinds of nutrients and the right amount of energy for an individual.

Fibre

A substance mostly made of cellulose that helps the digestive system stay healthy and prevents constipation.

Embryo

A little ball of cells produced from the division of a single cell during the early stages of human growth.

Development

The process of changes that occur as an organism grows, such as the formation of tissues and organs.

Nicotine

An addictive substance in tobacco smoke that narrows blood vessels and increases heart disease risk.

Tar

A dark, sticky mixture of substances in tobacco smoke containing chemicals that cause cancer.

Carbon monoxide

A poisonous gas in tobacco smoke that prevents haemoglobin from transporting oxygen.

Particulates

Tiny particles in tobacco smoke that get trapped inside the lungs and damage the alveoli walls.

Exoskeleton

A skeleton on the outside of the body, found in insects and other arthropods.

Joint

A place in the skeleton where two bones meet and movement takes place.

Hinge joints

Joints that allow bones to move back and forth in one direction, such as the elbow.

Ball-and-socket joints

Joints that allow bones to move in a complete circle, such as at the shoulder.

Tendons

Tough cords that attach muscles to bones.

Biceps

The muscle that contracts to pull on the radius and bend the arm at the elbow.

Triceps

The muscle that contracts to pull on the ulna and straighten the arm at the elbow.

Antagonistic muscles

A pair of muscles that work together so that when one contracts, the other relaxes to move a joint.

Exothermic reaction

A chemical reaction, such as combustion, in which thermal energy is given out to the environment.

Fuel

A substance, like charcoal or natural gas, that contains a store of chemical energy released during burning.

Oxidation reaction

Any reaction in which a substance combines with oxygen to form an oxide.

Endothermic reaction

A chemical reaction that absorbs thermal energy from its surroundings, causing a temperature drop.

Endothermic process

A physical change, such as ice melting or a substance dissolving, that absorbs thermal energy.

Inert

A term describing unreactive metals, such as gold.

Rust

An orange-brown solid called iron oxide formed when iron reacts with oxygen and water.

Galvanised iron

Iron covered with a layer of zinc to prevent oxygen from reaching the metal and causing rust.

Salt

A type of chemical product, such as magnesium chloride, formed when a metal reacts with an acid.

Magnetic field

The area around a magnet where effects like attraction or repulsion can be detected.

Magnetic north

The point close to Earth's geographic North Pole toward which a compass needle points.

Electromagnet

A magnet made by wrapping a wire coil around a magnetic core and passing an electric current through it.

Soft iron

Iron that is easily magnetised and demagnetised, frequently used as a core for electromagnets.

Factors affecting electromagnet strength

The number of turns in the coil, the material of the core, and the amount of electric current.