End of term test, semester 2 Flashcards
definition of electricity
a form of energy resulting from the existence of charged particles.
charge definition
fundamental property of materials.
are atoms neutral, positively charged or negatively charged
neutral.
can electrons be transferred? yes/no
yes.
number of protons=
number of electrons.
what are the two types of electricity?
static and current.
what is static electricity?
the build up of electric charge on a surface.
what is current?
a electrical current is formed whenever charge flows from one spot to another.
what are the laws of charges?
- alike charges repel.
- unlike charges attract.
eg. N/N, S/S - repel
N/S - attract
what is a magnetic field?
a region around a magnetic material or a moving electric charge within which the force of magnetism acts.
what is the law of poles?
- alike poles repel
- unlike poles attract
what are circuit components?
different parts of circuits.
what are circuit diagrams?
circuit diagram is a simplified and shorthand version of a real circuit.
what is voltage?
voltage is a measure of the amount of energy.
measured with a voltmeter.
what are conductors?
Metals are conductors. Electrical currents pass through them.
what are insulators?
some materials have such a high have a high resistance that they block electric current completely.
what is a series circuit?
in a series all the components of the circuit are connected up one after another to form a single loop.
what is a parallel circuit?
a parallel circuit has a number of branches, each branch having its own component.
what is electromagnetism?
Magnetism produced by an electric current and electric current produced by a changing magnetic field.
what is magnetism?
around a permanent magnet is an invisible force filed called a magnetic field.
what is a electric motor?
two magnets experiencing a force when place within each others fields.
what is a generator?
a generator uses electromagnetism to create electricity.
what is bacteria?
bacteria are microscopic, unicellular organisms.
what is a disease?
anything that causes our body to stop working properly.
what is a pathogen?
an organism that causes disease.
example of pathogens.
- viruses
- bacteria
- fungi
what is a disease caused by a virus, bacteria and fungi?
virus- rabies
bacteria- whooping cough
fungi- athletes foot
transmission definiton
the passing of disease from infected individuals to unaffected individuals.
methods of transmission
- droplet transmission
- transmission through water
- transmission through vectors
- transmission by contact
entry points of pathogens in the body
eyes, nose, mouth, skin, genitals, ears, cuts
what are the three lines of defence?
- producing antitoxins
- engulfing microbes
- releasing antibodies
producing antibodies
chemicals that are designed to neutralise the effects of the toxin and kill them off are released.
engulfing microbes
some cells eat the microbes and the break them down once they are inside the cell.
releasing antibodies
the antibody attaches itself to the specific site and then destroys it.
why are vaccines so important?
vaccines help out the body to develop immunity.
what is a vaccine?
a chemical that causes your body to react as if it had encounter a pathogen.
