Y7 4.2 Organisation
Plants
Plants need to go through a process
called photosynthesis to make their food
(glucose).
Lifestyle
Smoking – can cause lung disease and
smoke contains many dangerous chemicals
Drinking alcohol – can cause liver and
kidney problems
Poor diet – can cause obesity, diabetes or
heart disease
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Arteries – blood vessels that
carry blood Away from the
heart. They have thick muscular
walls to withstand high
pressure.
Veins – blood vessels that carry
blood IN to the heart. Veins
have valves. They have thinner
muscular walls since the
pressure isn’t very high.
Capillaries – small blood vessels
that carry blood everywhere in
the body where there aren’t
veins or arteries. They have thin
leaky walls for gas exchange.
Key words:
Cell: Building blocks of life.
Tissue: Group of similar cells working together.
Organ: Group of similar tissues working together.
Organ system: Group of organs working together.
Multicellular: Many types of cells or more than one
cell.
Organism: A living thing, e.g. an animal or plant.
Enzyme: A chemical which has a specific job to do,
e.g. break down fats.
Blood: A liquid made up of white and red blood cells,
and platelets. It carries oxygen and nutrients round
our bodies.
Pathogen: A microscopic cell that causes illness or
disease, e.g. bacteria, virus or fungus.
Lifestyle: The way a person lives, e.g. they drink
alcohol or exercise a lot.
Enzyme
Organ it’s
produced by
What it
breaks down
Amylase
Salivary
glands,
pancreas,
small
intestine
Starch into
sugars
Lipase
Pancreas,
small
intestine
Fats into fatty
acids and
glycerol
Protease
Stomach,
pancreas,
small
intestine
Proteins into
amino acids
Mouth: Uses teeth and saliva
which has enzymes in it to break
food
Oesophagus (food pipe): Muscles
push the food to the stomach
Stomach: Food gets further
digested by enzymes and it is
acidic.
Small intestines: Food and water
gets absorbed into the blood
Large intestine: More water and
minerals are absorbed what is
left over forms faeces (poo)
oesophagus
Density equation
Y7 6.3 particle matter
• Solids have a higher density
than liquids and gases.
• Liquids have a higher density
than gases, but a lower density
than solids.
• Gases have a lower density than
solids and liquid.
Pressure (p) = force (f)/ area (a)
p=f/a
a=f/p
f=pxa
The pressure law states:
"For a fixed mass of gas,
at a constant volume,
the pressure (p) is
directly proportional to
the temperature (T)."
m is in kg
d is in kg/m3
v is in m3
Key words:
Density: How tightly packed particles are in a
certain volume. A high density would have tightly
packed particles.
Particle: A small piece of matter, e.g. neutrons,
protons, electrons, atoms or molecules.
Matter: What everything is made up of.
State of matter: Solids, liquids or gases.
Melt: When solids turn into liquids.
Freeze: When liquids turn into solids.
Evaporating: When a liquid turns into a gas.
Condensation: When a gas turns into a liquid.
Chemical change: When a chemical reaction happens
and forms a new product.
Physical change: When the state of matter
changes, but nothing new is made.
Conservation of mass
This is when the mass started with is
the same as the mass at the end.
Mass can’t disappear or be destroyed.
Physical change
• Reversible change (can be
changed back)
• No new things are made
• E.g. melting, freezing,
evaporating
Chemical change
• Permanent change
• Can’t be changed back
• New things are made
• Energy give of (heat/ light)
• Colour change
• Fizzing
Y7 5.6 Rates of reaction
If the temperature is
increased:
the reactant particles
move more quickly
they have more energy
the particles collide more
often, and more of the
collisions result in a
reaction
the rate of reaction
increases
Key words:
Concentration: How many particles are in a
set volume.
Surface area: The available surface for
particles to collide and react.
Pressure: The same amount of particles with
either lots or not much space available to
move around.
Catalyst: A chemical that helps speed up a
reaction, but doesn’t get used up itself.
Temperature: A measurement of the amount
of heat, measured in Celsius or Fahrenheit.
Rate: How fast something happens.
Reaction: When particles of chemicals
collide and form a new product.
Collision: When particles hit into each other.
Kinetic energy: The energy things have when
they are moving.
Activation energy: The amount of energy
particles need to collide with, for them to
result in a reaction.
Collision theory
For a reaction to happen, particles have to
collide with enough energy (activation energy).
When they react, this is because of a
successful collision between reactant particles.
The higher the concentration, the
faster the reaction. The lower the
concentration, the slower the reaction.
The higher the surface area, the
faster the reaction. The lower the
surface area, the slower the reaction.