Year 8 science flash cards
What is an enzyme?
A biological catalyst that breaks down large molecules into smaller ones.
What type of enzyme breaks down carbohydrates?
Carbohydrase
What is an example of a carbohydrase?
Amylase
What type of enzyme breaks down protein?
Protease
What type of enzyme breaks down lipids?
Lipase
What are the two methods of digestion?
Mechanical and chemical
What is the name of the muscular movements of the digestive tract?
Peristalsis
What are different types of nutrients?
Proteins
Carbs
Fibre
Water
Lipids
Vitamins
Minerals
What do proteins needed for?
Muscle growth and produce protein such as enzyme in the body
What are carbs?
Carbs are needed for energy and storage
What is lipids needed for?
Provide energy, provide cushioning around vita organs, form part of cell membranes.
What are the processes of digestion of food?
Mouth; mixes food and saliva and breaks food particles down into smaller chunks
Oesophagus; brings the food down to the stomach.
Stomach; muscular contractions mix food with acid and pepsin which breaks food into smaller pieces and starts the process of protein digestion
Small intestine; juices from the pancreas, containing enzymes, mix with the food and chemically break it down into small, absorbable molecules which are absorbed across the wall of the small intestine.
Large intestine; this where water is absorbed leaving indigestible material behind and this collects in the rectum and is excreted through the anus.
What factors affect the function of enzymes?
Amount of substrate available.
Presence of toxins
The amount of enzymes available.
Temperature
Ph of the surroundings
Suface area of food particles
what is the name of the structure across which digested food molecules are absorbed?
Villi
Sometimes can be referred to as a brush boarder
What makes the wall of the small intestine a good exchange surface?
Large surface area {due to villi and micro villi}
Good blood supply
It has thin cells to provide a short diffusion distance
What is kinetic energy?
`energy that is associated with moving objects
What is thermal energy?
Energy that is associated with heat
What is gravitational potential energy?
Energy that is associated with hight ina gravitational field.
What is sound energy?
associated with vibrations that travel through a medium
What is elastic energy ?
Energy stored in stretchy object
What is the law of conservation of energy?
Energy can’t be created or destroyed. It is converted from one form to another.
What is the purpose of distillation?
Separates two liquids with different boiling points.
What is the purpose of filtration?
To separate a undissolved solute from a solvent.
What is a solvent?
A substance that is capable of dissolving other substances
What is a solute?
A substance that is capable of dissolving in a solvent
What is the purpose of chromatography?
To Separate coloured pigments in a dye.
What is the purpose of evaporation?
Separate a dissolved solute from a solvent by evaporating it away
what is salt produced with hydrochloric acid?
metal chloride
what salt is produced with sulfuric acid?
metal sulphate
what is salt is produced with nitric acid?
metal nitrate
what is adaptation?
The process by which oranism’s fitted to charcteristics to help survival in its environment through natural selection.
what do animals fight for ?
territory, mates, food, water
what is interdependance?
it is the relationship between two different species.
what is hibernation?
Hibernation is a deep sleep that helps animals survive in the winter time and save energy without eating much food.
what is migration?
migration happens for different reasons. Many migrate to breed or to find food.
how many chromosomes do humans have?
46 chromosomes
what is a force?
it is a push or a pull that has the ability to change it shape, speed or direction.
what is the law of moments?
anticlockwise moments = clockwise moments
what is speed?
Distance travelled per unit time
what is pressure?
The force per unit area
what does the group number tell us?
the amount of electrons of the outer shell of the atom
what does the period tell us?
the number electron shells in the atom
what is the mass number?
the number of protons and neutrons in the nucleus of the atom
what is the atomic number?
the number of protons in an atom
