lab #2 flashcards

symbiotic

close, long-term relationship where two different species live together and interact

eukaryotic

cells that have a nucleus surrounded by a membrane containing their dna

peptidoglycan

a large protein-carbohydrate polymer consisting of interlocking chains of identical monomers

binary fission

when one cell duplicated and divides into two cells identical to the parent cell

kingdom monera

refers to the fact that most of its members are single-celled organisms

domain

the highest most broad category of biological classification

cyanobacteria

group of photosynthetic bacteria, often called blue-green algae, that make their own food using sunlight and release oxygen

mordant

a substance used to set or fix dyes, helping the stain stick strongly to the cells

magnification

the process of enlarging the apparent size of an object

resolution

the ability to distinguish between two closely spaced objects or details

objective lens

the lens closest to the specimen, which initially magnifies the image

ocular lens

the lens at the top that you look through, which further magnifies the image

stage

the platform where the specimen slide is placed for viewing

light source

provides illumination that passes through the specimen

diaphragm

controls the amount of light passing through the specimen

focus

the process of adjusting the lens system to create a clear image

coarse adjustment knob

used for large, initial focusing adjustments, typically under low power

fine adjustment knob

used for small, precise focusing adjustments, especially under high power

compound microscope

allows us to see objects that are too difficult or small to see with the naked eye

objective lenses objectives

scanning: 4x, low-power: 10x, high-power: 40x, oil-immersion: 100x

stereo microscope

used to view relatively large objects, somewhat visible at the naked eye

ocular lenses for stereo

10x magnification

objective lens for stereo

2x or 4x (depending)

total magnification

ocular lens magnification x objective lens magnification (blank x 10)

resolving power

ability to distinguish two objects close together or two points/lines in an object under the microscope

working distance

distance between the specimen and the objective lens, decreases as magnification increases

field of view

circle of light or visible area when looking through eyepiece, decreases as magnification increases; eq: (diameter of FOV x 4) / (objective mag)

depth of field

the vertical distance with which structures are in sharp focus, decreases as magnification increases

taxonomy

science of classifying organisms according to their degree of similarity (DKPCOFGS)

scientific name

consists of both the genus and species name of an organism; genus is always capitalized + italisized

archaea

relatively rare organisms; thrive in extremely harsh environments; genetic material more closely related to eukaryotes than bacteria

bacteria (prokaryotes)

unicellular, some colonial; contain a cell wall exterior to cell membrane; some move with flagella

prokaryotes

lack a true nucleus + other membrane bound organelles

bacteria shapes

bacilus: rod, coccus: spheres, spirilum: spiral

sapotrophs

nutrients obtained from decaying or dead organisms

bacteria reproduction

asexually (binary fission like mitosis), sexually (conjugation by exchanging genetic material through a tube)

antibiotics

chemicals derived from certain organisms used to inhibit growth of microorganisms + prevent/treat infectious disease

antiseptics

substances used to control the growth of disease-causing microorganisms on living tissues

disinfectants

control bacterial growth on inanimate objects

zone of inhibition

circular area around the spot of the antibiotic in which the bacteria colonies do not grow; can be used to measure the susceptibility of the bacteria towards the antibiotic; the large the ZOI diameter, the better the antibiotic

gram negative bacteria (cell wall)

more complex cell wall, less peptidoglycan, appears pink

gram positive bacteria (cell wall)

cell walls rich in peptidoglycan, appear blue after staining