Glossary's Flashcards
REMEMBER
Antibiotic
A medicine that weakens or destroys microbes such as bacteria and fungi; antibiotics have no effect on viruses
Bacteria
Microscopic organisms forming one of the six kingdoms of living things; some types of bacteria are pathogens
Cell
the smallest functional unit of life; every cell in the body needs to obtain nutrients and energy, and get rid of wastes, to stay alive
Commensalism
A type of symbiotic relationship in which one organism benefits and the other organism neither benefits nor is harmed
Mutualism
A type of symbiotic relationship in which both organisms benefit
Parasitism
A type of symbiotic relationship in which one organism benefits and the other organism is harmed
Archaea
Microscopic organisms forming one of the six kingdoms of living things
Electron Microscope
A type of microscope that uses beams of electrons instead of light; electron microscopes are much more powerful than traditional light microscopes – for example, giving us detailed images of the inner structure of cells
Fungus
One of the six kingdoms of living things, including mushrooms, moulds and yeasts
Genetic Material:
The material within a cell that determines how it functions
Genetics
The features of an organism that are inherited from its parents
Hormone
A substance produced by the body to control a particular function, such as hunger, sleep or growth
Immune System
The body system that defends the body against infections
Infection
The presence of a pathogen inside the body
Inflammation
The process in which an infected area of the body becomes red, swollen and hot
Metabolism
The chemical reactions that take place in cells to keep them alive
Metabolic Disease
A medical condition that disrupts the conversion of food into energy within cells
Anus
The opening at the end of the digestive tract through which wastes are expelled as faeces
Bowels
Another name for the large intestine
Diet
The types of food that a person or animal usually eats
Digestion
The process of breaking down complex foods into simple nutrients that the body can absorb
Digestive System
The body system that breaks down food and absorbs the nutrients it contains; includes the mouth, stomach, liver, intestines and other organs
Digestive Tract
The series of tubes and cavities that food passes through as it is broken down
DNA
The chemical that makes up the genetic material in most organisms; deoxyribonucleic acid
Faeces
Solid waste that remains after food is digested, expelled out of the body through the anus
Gall Bladder
A small pouch-like organ between the liver and the small intestine, where bile is stored
Gut Microbiome
The community of microbes living in the intestines; this is the largest part of the body’s total microbiome
Large Intestine
The part of the digestive tract between the small intestine and the anus; its main function is to absorb water from digested food and provide a home for bacteria that break down complex carbohydrates
Liver
A large organ located next to the stomach that has many important functions; produces bile and releases it into the small intestine to help digest fats
Microbe
A living thing that can only be seen with the help of a microscope
Microbiology
The scientific study of microbes
Microbiome
A population of microbes living in a particular environment, such as on and inside a person’s body
Micrometre
A unit of length, one millionth of a metre; 1,000,000 micrometres (μm) are equal to 1 metre (m)
Micro-organism
A living thing that can only be seen with the help of a microscope
Nutrient
A substance that the body needs to be healthy, usually obtained from food; some nutrients are provided by “friendly” microbes living in the gut
Oesophagus
A long muscular tube, the part of the digestive tract that connects the throat to the stomach
Organ
A part of the body that performs a particular role, such as the heart, liver or brain
Organism
A living thing; something that is made up of one or more cells, and typically can grow, reproduce, take in nutrients, get rid of wastes and respond to its environment
Pancreas
An organ behind the stomach that produces enzymes to help break down food in the small intestine
Parasite
An organism that benefits from another organism (its host) while causing it harm
Pathogen
A microscopic organism that can cause disease
Prebiotic
A substance that passes undigested through the stomach and small intestine but is broken down in the large intestine and provides fuel for the friendly bacteria living there
Probiotics
Live bacteria that are thought to help promote health by reducing the number of harmful bacteria in our guts
Protists
One of the six kingdoms of living things
Protozoa
Single-celled organisms belonging to the kingdom of protists, including amoebas
Resilient
Able to recover quickly from damage or difficulties
Regulate:
To control
Scientific notation
A way of writing very large or very small numbers using powers; for example, 6500 would be written as 6.5 x 10^3
Secretion
The production and release of a substance from an organ of the body, such as saliva from the saliva glands
SI Unit
A unit of measurement that has been agreed on as part of the International System of Units, allowing scientists from around the world to communicate easily with each other; examples include the metre (m), the kilogram (kg) and the second (s)
Small Intestine
The section of the digestive tract between the stomach and the large intestine; its main functions are to continue breaking down food and absorb the nutrients released
Sterile
Free from bacteria and other microbes
Stomach
The part of the digestive tract between the oesophagus and the small intestine; a bag of muscle that churns and mashes food, and releases gastric juices to help break it down
Symbiotic relationship
A long-term interaction between organisms of different species in which one of the organisms benefits from the other; the second organism may also benefit (mutualism), may be harmed (parasitism) or may be unaffected (commensalism)
Virus
A type of microscopic pathogen that can only multiply by invading a living cell
Algae
Plant like organism that mainly live in aquatic environments. Main characteristics are their cells have membrane-bound nuclei (we call them eukaryotic) and they contain chlorophyll and carry out photosynthesis.
Centimetre (cm)
0.01m. There are 100 centimetres in 1 metre.
Chemical Preservatives
Salt, sugar and vinegar are common household substances used to preserve foods. Other unnatural additives can be used, but are becoming less common.
Decomposer
Microbes that break down the carbohydrates, proteins and fats of dead organisms. They recycle matter in the environment.
Drying Food
A preservation technique used on meat, fish, vegetables and fruit. It removes one of the necessities of microbes – water.
Fermentation
The process where yeasts feed on the sugars in fruits or vegetables, changing the sugars into alcohol and carbon dioxide. Used in the making of bread and fermented drinks such as beer, wine, cider and ginger beer.
Freezing
Storing food and drinks at temperatures between -10°C and -18°C.
Heat sterilisation
Heating under pressure at 120°C for 15 minutes. Used for canned and bottled food to slow down decay.
Irradiating
In terms of food, the use of radiation to kill harmful microbes or pests.
Lactobacillus
A bacterium used in making yoghurt, usually 2μm in length
Millimetre (mm)
0.001m. There are 1,000 millimetres in 1 metre.
Nanometre (nm)
0.000000001m. There are 1,000,000,000 centimetres in 1 metre.
Paramecium
A protozoa found in freshwater that has a length of 250 μm
Pasteurisation
Heating to 72°C for 15 seconds. Used for milk.
Refrigeration
Cooling food and drinks to 4°C to slow decomposition.
Variola
The virus that causes smallpox. Typical length of 0.3 μm
Yeast
A fungus which can be used to make bread rise or for fermentation in drinks, typically 10μm in length.
Adaptive Immune System
The part of the immune system that develops as the body learns to identify and target particular types of pathogen; it includes both specialized cells and substances (antibodies) that provide the body with a third line of defence against infection
Antibody
A substance produced by the immune system that circulates in the blood and is specialized to attack only one type of pathogen
Autopsy
The medial examination of a dead body
Blood Vessel
A tube that blood flows through within the circulatory system; there are three types: arteries, veins and capillaries
Cell Membrane
A thin layer that surrounds a cell, forming a barrier with the world outside but allowing some substances to pass in and out
Cytokine
A type of substance released by some cells within the immune system to signal other cells to respond to an infection
Dendritic Cell
A specialized type of cell that plays an important role in boosting the defences of the immune system
Dependent Variable
Something that is measured in an investigation, to see how it is affected by the independent variable
Diffusion
The movement of molecules from areas of high concentration to areas of low concentration
Ebola
A deadly infectious disease caused by the Ebola virus
Emerging Infectious Disease
An infectious disease that has appeared in a population only recently
Enzyme
A substance produced by the body to speed up a chemical reaction; for example, helping with chemical digestion
Eukaryote
A cell that has a nucleus, or a multicellular organism made up of this type of cell; animals, plants, fungi and protists are eukaryotes
Fever
A prolonged increase in core body temperature that helps fight an infection by making it too hot for pathogens to survive
First Line of Defence
The physical barriers that keep pathogens out of the body, including skin and mucus
Germ Theory
The theory that living germs can cause disease
Hypothesis
A proposed explanation used as the basis for an investigation
Immunity
Protection from infection
Immunologist
A scientist who studies the workings of the immune systems of humans or other animals
Incubation period
The time period from when someone is infected by a pathogen to when they start showing symptoms of a disease
Independent Variable
Something that is changed in an investigation to see what effect it has on the dependent variable
Infectious Disease
A medical condition caused by the presence of a pathogen within the body and that can be passed from one organism to another
Innate Immune System
The part of the immune system that we are born with and which provides non-specific (general) defence against all types of pathogens
Ligand
A molecule that binds to a receptor, triggering an immune response; a ligand matches a certain receptor like a key fitting a certain lock
Lysosome Sac
An organelle containing enzymes that break down unwanted materials
Macrophage
A type of large phagocyte that can stay in one place in the body or circulate in the blood as a white blood cell
Malaria
An infectious disease caused by protozoa, transmitted by mosquitoes in tropical regions
Membrane
A thin sheet that forms a barrier; molecules may be able to move through a membrane by diffusion
Model
A representation of something that is made out of physical objects or programmed in a computer; it is often much larger or smaller than the thing it represents
Mucu
A slimy fluid released by the lining of the airways to protect them
Non-Specific Defences
Elements of the innate immune system that are not specialized to fight specific types of pathogens; they include the first line of defence (skin and mucus) and the second line of defence (fever, inflammation and phagocytes)
Nucleus
A structure within a eukaryotic cell that contains genetic material
Organelle
A structure within a cell that has a specialized function, such as the nucleus
Permeability
The property of allowing liquids or gases to pass through (a material or membrane)
Phagocyte
A type of cell that is specialized to attack and destroy pathogens
Phagocytosis
The process by which a phagocyte surrounds a pathogen and destroys it
Protein
A chemical compound containing carbon, hydrogen, oxygen and nitrogen that performs a specific role in an organism
Receptor
A molecule on the outer surface of a phagocyte that allows it to attach to a ligand, e.g. on a virus; a ligand matches a certain receptor like a key fitting a certain lock
Second Line of Defence
The system of bodily responses that defend the body against pathogens once they have entered the body, including fever, inflammation and phagocytes
Stratum Corneum
The outermost layer of skin
Superspreader
A person infected with a pathogen who passes it on to an unusually large number of people
Third Line of Defence
The adaptive immune system that targets specific pathogens once they’ve entered the body, using specialized cells and antibodies
Vaccine
A substance that boosts a person’s immunity to a certain pathogen
White Blood Cell
A type of cell found in the blood that helps to protect the body from infection
Eradicate
To get rid of
Herd Immunity
The protection against an infectious disease that arises when a large proportion of a population is immune to it (for example, through vaccination); even individuals who are not immune are less likely to be exposed to infection
Innate immunity
Defences against infection that we are born with and which provide general protection against all types of pathogens
Memory Cell
A cell produced by the body following infection or vaccination that helps it defend itself against the same type of pathogen in the future
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