The scientific method and characteristics of life Flashcards
the scientific method
the processes of science that will lead to the discovery of new knowledge
8 steps in scientific method
observation hypothesis experiment result data conclusion reporting or publishing development of a theory or principal
hypothesis
a suggested explanation for an observation
experiment
the testing of a hypothesis
what does a good experiment need?
a sufficiently large sample size
result
the record or data collected during the experiment
what should the result be
should be able to be replicated or repeated
data
the information gathered during the experiment
conclusion
what the results say about the hypothesis ie. proven right or wrong
what is writing a report and why do it?
recording all the procedures so that others can repeat the experiment
where can you publish a report
in a scientific journal online
how can a hypothesis become a theory?
if its has been found to be true over time after repeated experimentation
how can a theory become a law or principle?
if it is applied over many years
7 things every experiment should have
- careful planning and design
- should be safe
- a control experiment for comparison
- large sample size
- samples sould be randomly tested
- must be repeatable
- double-blind testing
variable
any condition that changes during an experiment
how many variables allowed to change
generally one variable allowed to change and the others held constant
3 examples of safety features of an experiment
wear safety googles
wash hands after
read safety information on bottle of chemicals
why is a control important
to compare the experimental results with
replicates
repeats of an experiment and results
double blind testing
neither the person being tested or the person administering the drug knows who’s receiving the real or the placebo
purpose of double blind testing
eliminates bias
6 limitation of scientific method
the extent of our knowledge the basis of investigation our ability to interpret results changes in the natural world accidental discoveries ethical issues
explain how the basis of investigation is a limitation
poorly designed experiments, poor results
explain how changes in the natural world is a limitation
many hypotheses must be continuously altered
1 accidental discovery
penicillin by sir alexander flemming
1 ethical issue
the use of stem cells from human embryos
biology
the study of life
metabolism
the sum of all the chemical reactions in an organism
metabolic reaction
chemical reaction in a cell
anabolic reactions
the use of simple molecules to make more complex molecules
energy required
eg. photosynthesis
catabolic reactions
the breakdown of complex molecules into simpler ones
energy is released
eg. respiration
the continuity of life
living things arise from other living things
5 characteristics of life
organisation nutrition excretion response reproduction
organisation
cell, tissue, organ, organ system, organism, population
unicellular
one cell eg. ameoba
nutrition
the way in which organisms obtain and use their food
autotrophs
make their own food
heterotrophs
cannot make their own food, must obtain from the environment
excretion
the removal from the body of waste products made in the body
response
reacting to stimuli in their environment
sexual reproduction
fusion of a male sperm cell and a female egg cell to form a zygote which can grow into an individual
asexual reproduction
involves cell division and offspring identical to the parent
