Year 9 Science End of Years

Includes: Bang goes that theory, Heat my house, What are you eating

Evaporation

Slow change from liquid to gas state

Sublimation

Direct change from a solid to a gas state

Freezing

When a liquid turns to the solid state

Freezing point

Temperature at which a liquid turns solid as it cools

Boiling

When a liquid is heated and turns rapidly into a gas

State of matter

Either a solid, liquid or gas

Condensation

When water vapour turns back into liquid water

Change of state

Change between any of the states of matter

Physical change

Change in some physical property of matter

When temperature increases so does the ___ of the particles

Kinetic energy

Melting

When a solid is heated and turns into a liquid

Boiling point

Temperature at which a liquid boils

Aim

What you want to find out

Hypothesis

A prediction based on your scientific knowledge

Method

A description of how to carry out the experiment

Independent variable

The variable that is changed by you in the experiment

Dependent variable

The variable that is measured throughout the experiment and recorded in the results table

Controlled variables

All the variables that are kept constant in an experiment

Results

The observations you make during the experiment

Conclusion

The answer to the aim, it is often a trend seen in a graph or results tabl

lens

focuses light rays onto the back of the retina

Iris

controls the amount of light that enters the eye, coloured part of the eye

Sclera

the supporting wall of the eyeball, white part of the eye

Pupil

hole that allows light to enter the eye

retina

contains cells that are sensitive to light

optic nerve

transmits the image to the brain

cornea

begins the refraction of light rays that enter the eye

blind spot

where the optic nerve attaches to the retina, it does not contain light sensitive cells

day

the time it takes for a planet to do one complete rotation on its axis

lunar eclipse

when the earth passes between the moon and the sun and casts a shadow onto the moon so the moon can't be seen

solar eclipse

the moon passes in front of the sun and casts a shadow onto the earth so that the sun can't be see

Source of light

something that produces light directly

Reflector of light

do not produce light themselves but bounce light rays off their surfaces

Oqaque

No light can pass through this object

Translucent

Some light can pass through this object

Transparent

All light can pass through this object

Transmitted

when light passes through an object

What happens when light energy is absorbed?

it changes into heat energy

What 3 things can happen when light rays hit the surface of an object?

absorption, reflection, refraction

Reflection

Occurs when light rays bounce off an object

Refraction

Occurs when light rays bend as they pass through an object

Medium

The name given to a substance/object that light rays can pass through

Plane mirror

A flat mirror that reflects light

Angle of incidence

The angle between the incident ray and the normal

Angle of reflection

The angle between the reflected ray and the normal

The normal

a line perpendicular to the surface at the point of contact

Ray of incidence

the incoming light ray

Ray of reflection

the reflected light ray

Rules for drawing ray diagrams

Rule all straight lines, draw arrows in the correct direction on both the incidence and reflected ray

Type of mirror that curves inwards

Concave

Type of mirror that curves outwards

Convex

Ingestion

the taking in of food

Digestion

the breakdown of large food molecules into smaller ones

Physical digestion

the mechanical breakdown of large food molecules into smaller ones

Chemical digestion

the break down of food molecules into their building blocks using digestive juices

Absorption

digested food passing from the small intestine into the bloodstream

Egestion

the removal of undigested food from the anus

Teeth

mechanically digests food so that it is small enough to be swallowed

Saliva

moistens food and contains an enzyme which chemically digests starch

Oesphagus

the tube that connects the mouth to the stomach

Stomach

stores food, also chemically and physically digests food

Small intestine

finishes the chemical digestion of food and absorbs the digested food

Appendix

has no function in humans

Large intestine

absorbs water and firms up faeces

Rectum

stores faeces

Anus

ring of muscle through which faeces exits the body

Liver

produces bile, a green liquid that helps to digest lipids

Gall bladder

stores bile before it is released

Pancreas

produces digestive enzymes, which are then secreted into the small intestin

Carbohydrates (building blocks)

simple sugars

Protein (building blocks)

amino acids

Lipids (building blocks)

glycerol and fatty acids

Carbohydrates (use)

energy for other life processes

Protein (use)

building blocks for cell structures

Lipids (use)

energy and for the absorption of fat soluble vitamins

Vitamins (use)

for the proper functioning of many chemical reactions in the body

Minerals (use)

to make some of the structures in the body

Fibre (use)

to bulk up faeces

Water (use)

all chemical reactions inside the body take place in water

Balanced diet

an appropriate amount of all 7 food groups

Protein positive test

turns purple

Starch positive test

turns blue black

Glucose positive test

turns green, then yellow, then orange

Lipids positive test

oil remains on top of filter paper, becomes translucent