Quiz I Bio Lab 1 Flashcards
Draw and label out all parts of a microscope
Bacteria are ________
what are the characteristics?
prokaryotes
no nucleus
no organelles
single-celled
cell wall
very diverse
bacterial shapes -> look at slides and familiarize yourself with the microscopic photos
coccus
bacillus
sprillum
gram positive and gram negative
purple and pink/red respectively
cyanobacteria - photosynthetic prokaryotes
familiarize yourself with the images
nostoc and oscillitoia
autotrophs
producers that are able to make their own food by photosynthesis or chemosynthesis
photosynthesis
producing organic compounds using light energy
chemosynthesis
producing organic compounds by deriving energy from inorganic compounds
heterotrophs
consumers that must acquire energy from other organisms
saprotrophs
consumers that acquire nourishment from dead or decaying animals
compound light microscope
used to view extremely small objects or bacteria invisible to the naked eye
stereomicroscope
used to view larger objects that may be visible to the human eye
levels of magnification
40 = low 100 = medium 400 = high
field of view
the area of the slide seen through the microscope
taxonomy
the science that describes, names, and classifies organisms, both living and extinct, based on shared characteristics
scientific name
genus + species
homo (genus) sapiens (species)
scientific name for human
taxonomic levels
Domain kingdom phylum class order family genus species
domain
most inclusive level, newest level
three domains
archaea, bacteria, eukarya
what organisms do the domains archaea and bacteria include?
prokaryotic organisms
prokaryotic organism
very small cells that lack a nucleus and other membrane bound organelles
what organisms does the domain eukarya include?
eukaryotic organisms
eukaryotic organisms
cells with a nucleus and membrane bound organelles
how do the domains archaea and bacteria differ?
cell wall structure, membrane lipids, the way they synthesize proteins
what are some features in a bacteria cell?
plasma membrane, cytoplasm, ribosomes, DNA, cell walls, flagella, pili, capsule
ubiquitous
found virtually everywhere
binary fission
the process by which bacteria divide, simpler form of cell division
spherical bacteria
coccus
rod-shaped bacteria
bacillus
curved form of bacteria
spirillum
strep
when cocci and baccili stick together after cell division, these are chains or colonies that are formed
staph
spherical bacteria that also form colonies in clumps, these colonies are referred to as staph
gram staining
used to identify medically important bacteria
gram positive bacteria
retains crystal violet stain after treatment with iodine to set the stain and rinsed with alcohol
gram negative bacteria
loses the crystal violet stain when the alcohol is applied
heat-fixing
a method of killing bacteria and sticking them to the specific microscopic slide
cyanobacteria
chemically and physically similar to other bacteria, lack a true nucleus and membrane-bound organelles and divide by binary fission - autotrophs, lack chloroplasts but have chlorophyll and other pigments with which they perform photosynthesis
oscillatoria
a genus of filamentous cyanobacteria with over forty different species, named for its oscillating movement in water - reproduces by binary fission and fragmentation with the fragments growing into new longer filaments
nostoc
a genus of over ten species, made of round cells linked together like a string of beads
heterocysts
nostoc cells that fix atmospheric nitrogen into NH4 or into NO3- that can be used in building biomolecules such as proteins and DNA
nitrogen fixation
allows nostoc to survive in environments low in nitrogen, as nostoc disintegrate, they add nitrogen compounds to soil and water that are then available to other organisms
define autotrophs? Give four examples.
producers that are able to make their own food by photosynthesis or chemosynthesis - plants, algae, some bacteria, phytoplankton
define heterotrophs? give four examples
consumers that must acquire energy from other organisms - animals, fungi, most protozoa most bacteria
name the two types of microscopes that will be used in biology 102 labs
compound light microscope and stereomicroscope
where do you place a slide on a microscope?
the stage
define taxonomy
the science that describes, names, and classifies organisms, both living and extinct, based on shared characteristics
how are prokaryotic and eukaryotic cells different from each other?
prokaryotic are small and lack a nucleus along with other membrane bound organelles while eukaryotic tend to be much bigger and possess a nucleus along with membrane bound organelles
round bacterial cells in chains are called _______
strep
how long is iodine left on the slide during gram staining?
1 minute
what does the ubiquity of bacterial and fungal spores mean?
they are found virtually everywhere
where are the members of the genus oscillatoria found?
freshwater marine environment, wet soil
how can you control the amount of light coming through the microscope?
by adjusting the iris diaphragm
which level of taxonomy contains the largest number of species?
domain
what is the scientific name of humans?
homo sapiens
which bacterial shape is unicellular?
coccus
by what process do bacterial cells divide?
binary fission
what is meant by gram-negative bacteria?
when the crystal violet stain is lossed following the application of alcohol, the bacteria is gram-negative. this denotes resistance to antibiotics and a thin cell wall
which step in the gram stain technique removes the crystal violet stain from gram-negative bacteria
rinsing the slide with alcohol
which stain or solution was added to the smear after the crystal violet stain was rinsed with water?
iodine
name two factors that might affect the number of bacterial and fungi colonies growing on your culture plate
temperature and moisture
name two factors that might cause unexpected (contamination) bacterial or fungal growth on your culture plate
composition of the water used opening the plate and exposing into atmosphere prior to adding sample
