science ext

cell

the smallest unit of all living organisms

microorganism

organisms that can only be seen with a microscope

enzymes

biological catalysts that increases the rate of reaction

viruses

infectious microscopic agents

fermentation

metabolic process in which microorganisms such as bacteria, yeast, or fungi convert sugar and other organic compounds into various products, typically in the absence of oxygen

dysbiosis

refers to an imbalance in the gut microbiome where harmful bacteria may out number the beneficial ones

decomposers

organisms that feed on and break down dead plants or animal matter

soap

a salt of fatty acids that lifts/removes the small particles from surfaces

antiseptics

chemicals such as alcohol/weak hydrogen peroxide that kills microbes or prevent them from carrying out life processes

disinfectants

usually stronger chemicals such as bleach or quad as it kills microbes or prevents them from carrying out life processes

antibiotics

chemical substances that are taken orally or applied topically to kill or inhibit the life processes of bacteria

passive immunity

results when antibiotics are transferred to a person who has never been exposed to the pathogen

active immunity

the actions of your immune system in response to an infection by a pathogen

vaccination

stimulates an active immune response, allowing the person to produce antibodies wihtout developing the disease

herd immunity

occurs when a large proportion of the community become immune to the disease, making the spread of a disease from person to person unlikely

denaturing

when the enzyme’s structure breaks down, and the active site loses its shape

temperature

the average measure of kinetic energy of the particles in a substance

heat

the total kinetic and potential energy of the particles in a substance

conduction

transfer of heat energy through materials or between objects that are in direct contact, via the transfer of kinetic energy from vibrating molecules to neighbouring molecules, without the movement of object itself

convection

transfer of heat energy through the movement of fluid as particles are free to move.

radiation

transfer of heat erngy without particles of matter instead transferred through eolelctromagnetic waves

specific heat capacity

the amount of heat energy required to change the temperature of 1 kg of substance by 1 degree celsius of the substance

latent heat

the amount of heat energy required to change the state of 1 kg of substance

electromagnetic waves

they are produced by disturbance in electric and magnetic fields

refraction

The changing of speed and bending of wave as it passes through a medium into another with a different optical medium

total internal reflection

occurs when the angle of incidence is greater than the critical angle, adn the light is reflected back into the more dense medium. TIR can occur when the light ray is travelling from a more optically dense medium to a less optically dense medium 

critical angle

The angle of incidence which causes an angle of refraction of 90 deg. for a critical angle to exist, the light ray must go from a more optically dense medium to a less optically dense medium

diffraction

the bending/spreading out of a wave after passing through a corner or a gap

photon

a packet of light energy

nuclear fission

the splitting of a large atomic nucleus into smaller nuclei to release large amounts of energy

nuclear fusion

reaction in which two or more atomic nuclei combine to form a larger nucleus

oxidant

the species that is reduced and so causes the oxidation of another species

reductant

the species that is oxidised and so causes reduction of another species

incomplete combustion reaction

A carbon-containing fuel burning in insufficient oxygen to produce a mixture of products including CO, C, and H₂O

combustion reaction

A chemical reaction where a substance reacts with oxygen gas, releasing energy in the form of heat and light. When a carbon-containing fuel burns in sufficient oxygen, CO₂ and H₂O are produced.

aerobic respiration in bacteria

glucose + oxygen —> water + carbon dioxide + ATP

anaerobic respiration in bacteria

glucose —> lactic acid + ATP

anaerobic respiration in fungi

glucose —> ethanol + carbon dioxide +ATP

measles

Highly contagious, hence why to contain the spread of measles, it is estimated that 95% of the population must be vaccinated for herd immunity

meningitis

Is fast-acting, and can be lethal as it causes sepsis