BIOL 101L midterm Flashcards
(127 cards)
process of science
a way of gathering and testing information used by many people
a hypothesis must be…
testable
an experiment should be..
repeatable
objective observations
those that can be verified- repeated and consistently interpreted by different observers
subjective observation
they are observer specific and may not be interpreted in the same way by everyone
hypothesis
a tentative explanation of cause and effect based on underlying observed phenomena
independent. variable
the variable being changed
dependent variable
the variable being measured
control
where all the factors are the same as the test group, except the factor being tested is left in its normal, unmanipulated state
protocol
the description of steps in a scientific investigation
prokaryotic cells
lacks a nucleus and other membrane-bound organelles. Contains a nucleoid region contains DNA. prokaryotic contain ribosomes and various internal membranes
Prokaryotes
the term applied to organisms with prokaryotic organization. Found only in bacteria and archaea. generally unicellular. Some prokaryotes such as bacteria, have a cell wall and can use flagella for motility.
eukaryotic cells
have a distinct nucleus thats surrounded by a nuclear membrane. has membrane bound organelles.
when looking at a eukaryotic cell through a light microscope which organelles are easily identifiable?
nucleus, chloroplasts, cell wall, and other large plastids
which organisms lack membrane- bound organelles
prokaryotes
what role do bacteria play in the soil
they play an important role in nitrogen fixation
what is nitrogen fixation
converting nitrogen from the atmosphere into a form that can be used by plants
what is bacterias role as decomposers
they break down dead plants and animal and return the organic material to the system to the be used by other organisms.
are bacteria used in the production of foods such as cheese and yogurt
yes
are bacteria responsible for spoiling food and diseases
yes
Photosynthetic bacteria
use light as their energy source in a process similar to photosynthesis in plants; they don’t use water as their source of electrons for their photosynthetic process.
chemosynthetic bacteria
obtain their energy from the oxidation(loss of electrons) of inorganic substances
3 group of bacteria
bacilli, rod shaped; cocci, small sphere; spirilla, corkscrew-shaped
blue-green algae
photosynthetic; unlike other photosynthetic bacteria, but like photosynthetic eukaryotes these algae possess pigment chlorophyll a