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Bio CH 1
Sci Method, living things and classification
Question | Answer |
---|---|
Series of procedures that scientists use to solve scientific problems | scientific method |
hypothesis | an educated guess or a prediction that can be tested |
how do you test a hypothesis? | perform an experiment |
control | the standard to which the outcome of a test is compared |
variable | something in an experiment that can change |
independent variable | the variable that the experimenter manipulates/changes |
dependent variable | the variable that is measured by the experimenter. this variable responds to the manipulated variable. |
theory | an explanation of things or events based on scientific knowledge that is the result of many observations and experiments. This is not a guess or an opinion. |
SI (International System) units | the standard system of measurement scientists use to communicate and understand each others research and results. |
length | millimeter, centimeter, meter, kilometer |
volume | milliter, liter |
mass | gram, kilogram, tonne |
organism | any living thing |
cell | the smallest unit of life |
homeostasis | keeping the "home" stable. An organisms ability to keep the proper conditions inside no matter what is going on outside the organism. |
traits of all living things | organized into cells, respond to their environment, use energy, grow and develop, and reproduce |
raw materials | space to live, food and water |
spontaneous generation | the idea that living things come from nonliving things. ex: worms come from rain clouds. |
biogenesis | the theory that living things come from other living things. ex: mice give birth to mice. |
Louis Pasteur | a scientist in the 1800s that disproved spontaneous generation by doing an experiment with a swan-neck flask |
how old is earth | about 4.6 billion years old |
how old is life | about 3.5 billion years old |
what do scientists believe the first life form on Earth is? | single celled organisms (bacteria) |
where do scientists believe life originated? | in water/oceans |
phylogeny | evolutionary history of an organism or how it has changed over time |
binomial nomenclature | two-word naming system that is used to name various species- it consists of the genus and species of an organism |
who invented binomial nomenclature | Linnaeus |
which two categories are used in a scientific name? | genus and species |
Two-word scientific names are used for _____ reasons | help avoid mistakes, organisms with similar evolutionary histories are classified together, give descriptive information about the species, allow information about organisms to be organized easily and efficiently |
dichotomous key | detailed list of identifying characteristics that can be used to help identify and name a species. The list is arranged in steps with two descriptive statements at each step. |
cladogram | a graphic that shows evolutionary relationships between organisms |
derived characteristic/ derived character | trait |
outgroup | the organism on a cladogram that does not have any of the traits |
ingroup | any organisms that have some of the traits |
species | a group of organisms that can make fertile offspring |
hybrid | an animal, like a liger, that is made when two different species mate |
Redi | a scientist in the 1600s that disproved spontaneous generation with an experiment with flies and meat |
Needham | a scientist in the 1600s that said spontaneous generation happens with bacteria - his experiment was with broth |
Spallanzani | a scientist in the 1700s that disproved Needham's experiment by boiling the broth longer. His experiment supported biogenesis. |