Science Flashcards
Length
Standard unit = metre
instrument ruler
Volume
Amount of space it takes up
unit = metres cubed
instruments & methods - regular shape eg. cube is lengthXwidthXheight
Mass
The amount of matter in the object
standard unit kg
instrument = mass balance
Area
The amount of space enclosed within its boundary lines
standard unit metre squared
instrument = metre stick or trundle wheel
Rectangle formula
Length x width
Circle Formula
πr2 (Pi times the radius squared)
Triangle Formula
Half the base times the perpendicular height
Time
Unit = seconds
instrument = clocks
stopwatch or timer
Temperature
Unit = degrees Celsius
instrument = thermometer
Materials keywords
Solid, Liquid, Gas, Boiling Point, Melting Point, Freezing Point, Boiling, Melting, Condensation, Evaporation, Sublimation
Matter definition
Anything that occupies space and has mass
3 states of matter
Solid,
Liquid,
Gas
Matter is made of particles called?
Atoms
Particle Theory - Solids
Particles held together tightly don’t move,
Fixed pattern,
same shape,
tightly packed,
definite shape,
definite volume,
does not flow,
difficult to compress
Particle Theory - Liquid
No fixed pattern,
small spaces between them,
can slide over each other,
no definite shape,
definite volume,
difficult to compress,
flow easily
Particle Theory - Gas
Spreads out,
no pattern,
lots of space between,
no definite shape,
no definite volume,
easy to compress,
defuses to fill all available space
The Scientific Method
Find the question or problem,
Research information,
Hypothesis prediction,
Experiment to test the hypothesis,
Analise data,
Conclusion and communicate results
The individual parts of a cell are known as
Cell organelles
Structure of animal cells are
Cell membrane
Cytoplasm
Nucleus
Mitochondrion
Ribosome
Cell membrane
Allows substances in or out of the cell
Protects the cell
mostly made of fat
doesn’t allow everything through it
generally allows small substances through eg. water not large eg. protein
Cytoplasm
Watery fluid that organelles float in
mostly water with salts, glucose and other food materials in it
Nucleus
Contains genes that control the cell
Carries chromosomes which are made up of genes that control the working of the cell
Genes are made of
DNA
Mitochondrion
Where energy is released in respiration
“power-house of the cell”
where food reacts with oxygen to release energy
This process is called respiration
Ribosome
where proteins are made
eg. hormone insulin; enzyme amylase; collagen for the skin
Organelles only found in Plant Cells
Cell Wall
Vacuole
Chloroplast
Cell Wall
Support and protection
cellulose - a very strong substance giving great support and protection - fibre in food is cellulose
vacuole
storage of food and water
a space within the cytoplasm where the cell can store substances
Chloroplasts
Photosynthesis
the organelles in plants that contain the green chemical called chlorophyll.
Chlorophyll
traps light energy to be used in photosynthesis
Photosynthesis is
the way green plants make their own food using light
photo=light
synthesis=combine
Why do we need a digestive system?
Each cell in our body needs food to carry out its functions
This food is delivered by the bloodstream
Food we eat is mostly in large particles
These large particles need to be broken down to fit in blood and through cell membranes
a System is
a group of organs working together
Digest
to break down large food particles to smaller particles
Why do we need food?
Energy
Growth
Repair
Food is not used in the digestive system - it is used
in the cells
5 steps to provide nutrition for the body
Ingestion
Digestion
Absorption
Assimilation
Egestion
Ingestion
Taking in food - eating
Digestion
Breaking down the food
Absorption
The food passing into the blood system
Assimilation
The food being put to use by the cells eg. energy, growth, repair
Egestion
Passing any unabsorbed food out in the form of faeces (POO!)
Organs of the Digestive System
Mouth (with teeth)
Oesophagus
Stomach
Small intestine
Large intestine (colon)
Salivary glands
Liver
Gall bladder
Pancreas
Mouth (teeth)
Takes in food
Crush food with teeth
Amylase is added to food
Oesophagus
Carry food down to stomach
Stomach
Churn the food
Add acid to food
Small intestine
Further digestion by enzymes
Absorption of digested food into the blood
Large intestine (colon)
Water absorbed into the blood
Waste left prepared for egestion
Salivary glands
Make saliva which contains the enzyme amylase to break starch down into smaller sugars
Liver
Produces liquid Bile which helps digest fat
Regulates the amount of each food in the blood
Gall bladder
Stores Bile from the Liver until it is needed
Pancreas
Makes enzymes to break down food
Amylase
an enzyme that breaks starch down to a sugar, maltose
an Enzyme is
a chemical found in living organisms that speeds up chemical reactions
Peristalsis is
a muscular movement that only occurs in the muscles of the digestive system
used to push the food along
Teeth carry out
mechanical digestion
Incisors
cut and slice food
Canines
grip and tear food
Premolars
chew and grind food
Molars
chew and grind food
Chemical breakdown of food in the digestive system is carried out by
enzymes
The enzyme itself is not used up in the reaction - for this reason, it is known as a
catalyst
any chemical reaction that takes place in a living organism is known as a
biochemical reaction
an enzyme that breaks the maltose into glucose is
maltase
