General Definitions Flashcards
Scientific method
is a process of investigation where problems are identified and their explanations are tested by carrying out experiments
Observation
An unbiased, accurate report of an event.
Hypothesis
An educated guess based on observation
Experiment
An experiment is designed to test a hypothesis.
Data
Consists of measurements, observations/information gathered during an experiment.
Replicate
A repeat of an experiment
Control
A comparison used to provide a standard against which the actual experiment can be judged
Theory
A hypothesis that has been supported by different experiments
Principle/Law
A theory that has shown to be valid after long term testing
Ethics
Refers to whether issues are right or wrong
Continuity of life
Living things that arise from other living things of the same type (Biogenesis)
Metabolism
Sum of all chemical reactions in the body
Characteristics of life
The common features shared by living organisms
Organisation
Living things are composed of cells, tissues,organs and organ systems.
Nutrition
Process by which an organism obtain and uses food.
Excretion
Removal of waste products of metabolism
Response
The reaction of organisms to stimuli in their environment.
Reproduction
The production of new individuals.
Bio molecules
Molecules found in living things are composed of atoms where elements bonded together in different ratios to form biomolecules. Such as Carbohydrates, Lipids, Proteins and Vitamins.
Organic compounds
Carbon atoms bonded together make up most of the chemical compounds in living things.
Monosaccharides
Monosaccharides : Single sugar molecules such as Glucose.
Disaccharides
Disaccharides : 2 sugar molecules bonded together such as Sucrose,Lacotse and Maltose.
Polysaccharides
Polysaccharides : Made up of many sugar molecules bonded together. Eg - Starch, Glycogen and Cellulose
Phospholipid
Fat-like substances where one of the fatty acids is replaced/added a phosphate group.
Anabolic rxn
Convert smaller molecules into larger ones using energy
Catabolic rxn
Complex molecule is broken down to simple molecules. (Releasing energy)
Ecology
The study of the relationships of living organisms with one another and with the environment.
Ecosystem
A community of organisms and their abiotic environment.
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Habitat
Place in the environment where an organism lives.
Population
All the member of the same species living in an area.
Community
Plants and animals sharing the resources of a particular habitat.
Niche
The functional role of an organism in an ecosystem. Eg – How it feeds, what it
eats, who eats it etc.
Abiotic factors
Non living factors
Biotic factors
Living factors
Climactic factors
Refers to weather over a long period of time
Edaphic factors
Refers to the soil that influences an ecosystem eg: pH,type,moisture
Producers
Autotrophs that carry out photosynthesis
Consumers
Organisms that take in food from other organisms
Primary consumer
Organisms which feed directly on producers
Secondary consumers
Carnivores that feed on primary consumers
Tertiary consumers
Carnivores that feed on secondary consumers
Food chain.
The pathway along which energy is transferred in an ecosystem.
Food web
Two or more interlinked food chains
Trophies level
Is feeding stage/energy level in a food chain
Pyramid of numbers
Based on numbers of organisms at each trophic level in a food chain.
Nutrient recycling
The way in which elements (Carbon and Nitrogen) are exchanged between the living and non-living components of an ecosystem.
Nitrogen fixation
Conversion of nitrogen gas into ammonia (NH3), ammonium (NH4+) or nitrate ( NO3−)
Nitrification
The ammonia is converted to nitrites and then to nitrates by nitrifying bacteria.
Denitrification
Conversion of nitrates to nitrogen gas. It is carried out by denitrifying
bacteria in the soil.
Pollution
Any harmful addition to the environment
