Science Revision. Flashcards
Osmosis Definition.
Osmosis is the net movement of water molecules from a high water concentration to a low water concentration through a semi-permeable membrane.
Active Transport Definition.
The movement of particles/substances through a semipermeable membrane against a concentration gradient, using energy released through respiration.
Diffusion Definition.
The movement of particles from an area of high concentration to low concentration.
Photosynthesis Word Equation.
Carbon Dioxide + Water -> Glucose + Oxygen.
Natural Selection.
There is variation in characteristics within a population. If these characteristics allow a species to survive, those with the genes will reproduce and pass them on. Over time, a new species is created.
Who introduced the concept of Natural Selection?
Charles Darwin.
Large intestine function.
Absorb water.
Small intestine function.
Absorb nutrients, break down food and get rid of unecessary waste.
Liver function.
Produces bile - triangular shape on diagrams.
Gall bladder function.
Stores bile produced by the liver.
Oesophagus function.
Allows passage of food from the mouth and throat to the stomach.
Is this a plant or animal cell?
Plant cell.
Is this an animal or plant cell?
Animal cell.
What do plant cells have that animal cells don’t? (3)
Vacuoles, cell walls, chloroplasts.
Mitochondria function.
Release energy for the cell via aerobic respiration.
Nucleus function.
Controls the cells activities and contains the genetic material.
Cytoplasm function.
Jellylike substance where chemical reactions of the cell occur.
Cell membrane function.
Controls what enters/exits the cell.
Ribosomes function.
Site of protein synthesis - where proteins are made.
Cell wall function.
To support and strengthen the cell.
NOT FOR PROTECTION.
Vacuole function.
Keeps the cell rigid and provides support.
Chloroplasts function.
Contains chlorophyll where photosynthesis occurs.
Battery symbol.
Converts chemical energy into electrical potential energy.
Cell symbol.
Converts chemical energy into electrical potential energy.
Diode symbol.
Regulation of the flow of electricity, and to maintain constant voltage.
Voltmeter symbol.
Measures voltage/potential difference.
Thermistor symbol.
A resistor with a resistance dependent on temperature.
Resistor symbol.
A fixed resistor, so the resistance doesn’t change.
Variable resistor.
Increases the resistance in a circuit, and reduces the current.
Light Emitting Diode (LED).
An LED works in a circuit by emitting light when electrical current passes through it in the correct direction.
Lamp symbol.
Emits light.
Fuse.
The fuse breaks the circuit if a fault in an appliance causes too much current to flow.
Ammeter.
Measures the amount of current in a circuit.
Light Dependent Resistor (LDR) symbol.
Used to detect light levels.
Potential Difference Definition.
Potential difference (voltage) is a measure of energy, per unit of charge, transferred between two points in a circuit.
How is Potential Difference Calculated?
V = I * R, (Voltage = Current * Resistance)
Which type of circuit is categorised by having one loop.
Series circuit.
Which type of circuit is categorized by having several loops/branches.
Parallel circuit.
What is current measured in?
Amperes/ Amps/ A.
What is voltage measured in?
Volts/ V.
How is resistance calculated?
R = V/I - Resistance = Voltage / Current.
How is charge split in a series circuit?
Charge is split across components and is equal to the voltage of the supply.
If two identical components are connected in series, the supply voltage divides EQUALLY between them.
How is charge split in a parallel circuit?
The total current supplied is split between the components on different loops/branches.
If a component breaks in a series circuit, will the rest of the circuits continue to work?
No.
If a component breaks in a parallel circuit, will the rest of the components continue to work?
If a component in a parallel circuit breaks, the current will still be able to travel along the other unbroken branches. Therefore, the current on the other branches will still be able to work.
What is the equation linking speed, distance and time?
Speed = Distance / Time.
Rearrange the speed, distance, time equation so distance is the subject of the formula?
Distance = Speed * Time.