QUIZ 2 (BIOMOLECULES + PROKARYOTIC CELLS)

bacteria shapes:

- cocci (round) - bacilli (rod-shaped) - spirilla (spiral-shaped)

parts of bacteria cell

- granular bodies - ribosomes - cytoplasm - cell membrane - cell wall

carboxyl group (carboxylic acid)

A functional group present in organic acids and consisting of a single carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group.

amino group

A functional group that consists of a nitrogen atom bonded to two hydrogen atoms

Biomolecules

Organic molecules; they all contain five or more carbonj

cultures of bacteria

a clump of bacteria species

to view basic shapes of cells use:

a compound microscope with an oil immersion lens 100 to view basic morphology of bacteria cells, subcellular organelles will not be visible even at 100x

pure cultures

a single isolated bacteria species

photosynthetic

able to produce their own food

nitrogenous bases

adenine, thymine, cytosine, guanine, A-T, C-G

Negative lugol's test

amber/dark brown color

monomer (basic unit ) of protein

amino acid

polymer (chain of basic units)

amino acids form PEPTIDE BONDS to form proteins

TEM (transmission electron microscope)

approximately 1000x greater than a compound light microscope, use a TEM to observe the SUBCELLULAR structure of bacteria

in order to keep cultures pure: (free from contamination by bacteria present around us in air, water, soil, etc)

bacteria are grown on culture media (liquid or solid) that contains the nutrients necessary for bacterial growth

cells are categorized:

based on wether their organelles are membrane bound or free floating within cell's cytoplasm

CnH2nOn

carbohydrate general equation (ex C6H12O6)

4 classes of biomolecules:

carbohydrates, lipids, proteins, nucleic acids

carbohydrates

carbon, hydrogen, oxygen

proteins

carbon, hydrogen, oxygen, AND nitrogen

discrete colonies

colonies of bacteria that are produeced from the replication of a single bacterium, utse a steak plate or spread plate

bacterial cell walls contain

comprised layers of amino sugars called peptidoglycan

Lipids

contain same elements as carbohydrates (carbon, hydrogen, and oxygen), LONG carbon-hydrogen tails

gram positive

deep purple color of gram's stain

Nucleic acids

dna and rna are strands of nucleotides

primary stain

first stain applied in gram staining

hydrolysis

gaining of water

all monosaccharides, some disaccharides

have a free aldehyde or ketone group; functional groups/carbonyl groups, usually sweet smell, called reducing sugars but are not all

proline has an amino group bound in a ring, other amino acids:

have a free/unbound amino group

opposite to polar

hydrophilic (water lowing)

extremely non polar

hydrophobic (water hating)

Positive lugol's test

iodine atom reacts with bonds in long chains, blue black color

sudan iv is a

lipid dye and will form spherical droplets in the soolution

triglyceride

lipid found in our blood

condensation

loss of water

Quantitative test

measure something, numbers (ex number of, size of)

Positive benedict's test

medium concentration - green yellow high concentration - reddish orange

simplest unit (monomer) of carbohydrates

monosaccharide (ex glucose and fructose)

prokaryotic

most basic cellular form and have no membrane-bound organelles, no dna or nucleus, (ex bacteria, e coli, salmonella)

some disaccharides, all polysaccharides

no free reactive group (starch, cellulose, glycogen, chitin)

monomers of nucleic acids

nucleotides

Qualitative test

observation (ex color, present/absent)

bacteria that photsynthesize:

observe that the cell membrane folds forming an internal membrane system where the chlorophyll resides

structure of nucleic acids

phosphate group, pentose sugar (5 carbon), nitrogenous bases

they are: what type of biomolecule:

polysaccharides, carbohydrates

subculturing

pure cultures are produced by transferring one medium plate to another

positive biuret's test

purple (color fades after awhile)

positive ninhydrin test

purple, only proline is yellow

Not all carbohydrates are:

reducing sugars, some are starches which is tested separately

nucleoid

region of bacteria where genetic info is stored (DNA), may appear as a lighter fibrous area near the center of the cell

most organisms are heterotrophic:

require external sources for food

lipid structure

saturated (no double bond) - stacks, not fluid unsaturated (a few double bonds) fluid and does not stack, in our bodies and is good for us

polysaccharides

several monosaccharides linked together (ex cellulose (plant fiber); glycogen (stored form of glucose); chitin (cytoskeleton of insects))

Lugol's test

test for carbohydrates (NOT REDUCING SUGARS (starch)), permanently stains,o only add a few drops and hold up to light,

Benedict's Reagent

test for carbohydrates (ONLY REDUCING SUGARS), requires heat to react and is only test that does

sudan iv

test for lipids indicator, add water with this test, if lipids present, they will not mix with water and separate out, lipids WILL mix with the red sudan iv

Ninhydrin test

test for proteins (INDIVIDUAL AMINO ACIDS)

Biuret's test

test for proteins, instantaneous, reacts with peptide bonds, has no "c" for carbohydrates

20 different amino acids but:

the R (side chain) is different and unique for each one

unlikes plants whose chlorophyll is stored in chloroplasts, in cyanobacteria:

the chlorophyll is found dispersed throughout the cytoplasm within photosynthetic THYLAKOID MEMBRANES

counterstain

the second stain applied if a gram negative stain does not penetrate the protective layer

flagella

thread like organelles used for locomotion present on bacteria cells

disaccharide

two monosaccharides linked together (ex sucrose (table sugar); lactose (milk))

cyanobacteria are

unique to their shape and do not conform to the three basic structural shapes in bacteria, they are arranged in linear filaments

cyanobacteria

unique type of photosynthetic prokaryote that contains chlorophyll lla, the same cholorophyll found in algae and plants (eukaryotes) rather than the regular bacteriochlorophyll common to most photosynthetic prokaryotes

gram's stain

used to classify bacteria into 2 groups: gram positive or gram negative, the ability to contain the stain is dependent on the structure of the cell wall

some cells have a slime layer (capsule), of polysaccharides surrounding the bacterium:

when present, it functions as a layer of protection of some bacteria that help to keep the cells hydrated and shield the bacterium and attack by the host organism's immune system

mesosome

whorls of membranous material that extend inward from the cell membrane, these are hypothesized that they play a role in cell division and possible energy production of the cell

gram negative

will lose the color when washed with a decolorizing agent such as alcohol or acetone

liquid growth medium, broth, can be made solid:

with the addition of agar, a complex carbohydrate