science

Coordination

The process by which the body makes different systems work together so the organism responds appropriately to changes (internal & external).

Nervous system

Uses electrical impulses along nerves, providing fast (instant) messages and short-term effects.

Endocrine system

Uses hormones (chemical messengers) released into the bloodstream, acting slower (seconds-hours) with longer-lasting effects.

Hormones

Chemicals made by endocrine glands (e.g., pancreas, thyroid, adrenal glands) that travel through the bloodstream to target organs/cells.

Insulin

A hormone produced by the pancreas that lowers blood glucose.

Adrenaline

A hormone produced by adrenal glands that prepares the body for 'fight or flight'.

Homeostasis

Maintaining stable internal conditions despite external changes.

Negative feedback

Process where the body responds to a change by reversing it to return to stability.

Temperature regulation

Example of homeostasis where the body detects changes in temperature and counteracts them.

Waves

Transfer energy, not matter.

Longitudinal wave

Particles move back and forth in the same direction as the wave.

Transverse wave

Particles move up and down at right angles to the wave direction.

Frequency (f)

Number of waves per second (Hz).

Wavelength (λ)

Distance between two crests/troughs.

Speed (v)

How fast the wave travels.

Wave speed equation

v = fλ (wave speed = frequency × wavelength).

Sound

Needs particles to travel and cannot travel in a vacuum.

Pitch

Related to frequency of sound.

Loudness

Related to amplitude of sound.

Ultrasound

High-frequency sound waves used in medicine for imaging, breaking kidney stones, and measuring blood flow.

Reflection

Light bounces off surfaces, helping direct light into the eye.

Refraction

Light bends when passing through different materials.

Glasses/Contact lenses

Correct vision by bending light properly.

Laser eye surgery (LASIK)

Reshapes cornea to improve focus.

Cataract surgery

Removes cloudy lens and replaces it with an artificial lens.

Scientific method

Aim → hypothesis → method → results → conclusion.

Variables

Independent = changed; Dependent = measured; Controlled = kept same.

Validity

Testing what you're supposed to test.

Reliability

Consistency (repeat → same result).

Accuracy

Closeness to true value.

Analysing data

Spot trends, patterns, anomalies, then make conclusions.