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73 Cards in this Set
- Front
- Back
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metric units commonly used in biology
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meter, liter, kilogram and degree Celsius; based on units of 10
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deci; centi; milli; micro; nano; pico
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10 to the -1, -2, -3, -6, -9, -12
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deka, hecto, kilo, mega, giga
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10 to the + 1, 2, 3, 6, 9
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meter
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basic unit of length; units of area are squared
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volume
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space occupied by another object; units are cubed
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pipette
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used measure small volumes; drawn using a bulb
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graduated cylinder
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used to measure larger volumes;
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meniscus
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is curved due to surface tension and adhesion of water to the sides of the cylinder; always read at eye level
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mass is not always synonymous with weight...
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mass measures an objects potential to interact with gravity; weight is the force exerted by gravity on an object
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a weightless object
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is outer space has the same mass as it has on earth
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density
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= mass per unit volume; g/L
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temperature
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measure of the kinetic energy of molecules; the amount of heat in a system
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Celsius equals
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=5/9 (32+Fahrenheit)
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Fahrenheit equals
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=9/5 (Celsius-32)
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statistics
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offer a way to organize, summarize, and describe data; usually from a large population of values; allows us to make decision with having complete data
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mean
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arithmetic average of a group of measurements; high and low values tend to cxn themselves out, low chance of error
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median
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middle value of a group of measurements;
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significant figures
x and / + - |
x and / - round answer to lowest digit of all #s
+ and - - round answer to lowest decimal place |
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range
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difference between extreme measurements; smallest and largest
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standard deviation
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indicates how measurements vary about the mean; the mean +or- 1 SD includes 68% of the measurements, the mean +or- 2 SD includes 95% of the measurements
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sum of squared deviations
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calculating the mean, measure the deviation of each sample from the mean, square each deviation and the sum the deviations
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variance
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= sum of square deviations / N-1
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SD
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= square root of variance
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light microscope
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a coordinated system of lenses arranged to produce an enlarged, focusable image of a specimen; it magnifies a specimen
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resolution
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the ability to distinguish two points as separate points; better the resolution, the sharper the image appears
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contrast
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the amount of difference between the lightest and darkest parts of an image; dyes are often used
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a light microscope has two/three systems
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an illuminating system, an imaging system, and sometimes a viewing and recording system
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illuminating system
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which concentrates light on the specimen, usually consists of a light source, condenser lens and iris diaphragm
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light source
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a lightbulb located at base of microscope; illuminates the specimen by passing the light through a thin, transparent part of specimen
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condenser lens
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located immediately below the specimen; focuses light from the light source onto the specimen
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condenser iris diaphragm
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a knurled ring or lever that can be opened and closed to regulate the amount of light reaching the specimen
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open vs closed condenser iris diaphragm
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open - image is bright; closed - image is dimmed
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caring for microscope
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carry upright with hand under base and around arm; clean ocular and obj. lens w/lens paper; start on lowest power obj.; never allow lens to touch slide on obj. adjs.; on high power only use fine adj. to focus; clean lens again, wrap cord and return
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imaging system
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improves resolution and magnifies the image; consists of obj and ocular lenses and body tube
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objectives
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are 3 or 4 lenses mounted on a revolving nosepiece; a series of several lenses that magnify, improve resolution and correct aberrations in the image
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4 level magnification of objectives
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low magnification (4x); medium (10x); high (40x); oil immersion (100x) ; power of each is on side of lens
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oil immersion
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requires special instructions; to study bacteria
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ocular (eyepiece)
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the lens that you look through; monocular and binocular; magnification of 10x
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body tube
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a metal casing through which light passes to oculars
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stage
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secures the glass slide with stage clips on which the specimen is mounted
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viewing and recording system
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if present; converts radiation to a viewable and/or permanent image; camera or video;
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focus adjustments
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coarse for low/med power adj; and fine for high power adj
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how to use a light microscope
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place specimen on stage; rotate to low power and center specimen; use coarse to adj and center again; rotate to high and use fine to adj; if you lose, retrace steps and focus on centering specimen
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magnification of image
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= magnification of objective lens x magnification of ocular lens
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most light microscopes 2 things
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parfocal and parcentered
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parfocal
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the image will remain nearly focused after the 40x obj lens is moved into place
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parcentered
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the image will remain centered in the field of view after the 40x obj lens is in place
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field of view
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area that you can see through the ocular and obj; measured in micrometers
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ocular micrometer
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a small glass disk with thin lines numbered and etched in a row
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stage micrometers
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a glass slide having precisely spaced lines etched at known intervals
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depth of field
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thickness of the objects in sharp foucs
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micrometers
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used to calibrate microscopes and measure the size of specimens
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prepare a wet mount of bio specimen
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place drop of water on clean slide; place clean coverslip at 45 degree angle on edge; slowing lower coverslip on slide so no bubbles are trapped; begin obs at low power
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dissecting microscope
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(stereoscopic); use light source above specimen; mag 4x to 50x
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adv/disadv compound microscope
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can produce high magnification, excellent resolution; has small working distance and limited to thin specimen so light can pass thru; 2D
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working distance
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distance between obj lens and specimen
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adv/disadv dissecting microscope
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used to view objects that are opaque or too large to see with a compd; provides larger working distance; image is reflected in mirror; always bino; 3D image; lower res and mag than cmp
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cells
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basic unit of living organisms; perform all processes we call life
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cytology
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study of cellular structure and function; tools - light and electron microscope; cell chemistry
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prokaryotes
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bacteria and cyanobacteria; >5000 species; no nucleus, no organelles; reproduce asexually; they have mechanisms for genetic recombination
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Prokaryotes do have
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nucleoid region, ribosomes, plasma membrane, cytoplasm, cell wal, (@1500 have flagella
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organelles
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organized structures of macromolecules having a specialized function and are suspended in cytoplsam
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flagella
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used for movement; in prok
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pili
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(hairlike outgrowths); used to attach some types of bacteria to surfaces or to exchange genetic material w/other bacteria; in prok
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ribosomes
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small particles involved in protein synthesis
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nucleoid region
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concentrations or DNA
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cytoplasm
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enclosed by plasma membrane; enclosed within are ribosomes and nucleoid region
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levels of a bacterial cell; inner to outer
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cytoplasm; plasma membrane, cell wall, gelatinous capsule
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cyanobacteria
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largest prok; blue-green algae; contain chlorophyll and pigments for photosynthesis
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thylakoids
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photosynthetic membranes hold pigments in cyanobacteria
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mucilaginous sheath
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surround cyanobacteria; have ability to photosynthesis
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bacteria
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do not contain chlorophyll;
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Lactobacillus
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a bacterium adapted to live on milk sugar; used in diets to preserve milk
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