Microbiology Unit 2 - Cells

• layer of lipids that separates them from the outside world
• monolayer, bilayer, double membrane

ribosome assembly site

• A non coding sequence in a split gene
• Present in most eukaryotic cells

coding sequence in a split gene

• location in a prokaryotic cell where the prokaryotic DNA is located
• Eubacteria & Archae

• A defining characteristic of a Eukaryote
• Location where the chromosomes are located

Independently replicating pieces of DNA that are passed on to daughter cells that code for at least some essential genes

double membrane surrounding the nucleus

• extensions of the membrane into the cell sometimes forming sacs
• important for photosynthesis

• granules of ferromagnetic iron oxide localized close to the flagella
• allow magneotatic bacteria to migrate down in pond water to anaerobic environment

Made of a protein wall that forms a gas-tight sac

• Eukayotes
• Used for storage of food, maintenance of cell shape, elimination of waste

Eukayotes

small membrane sacs allow the breakdown of components that have been taken in from outside the cell or defective components w/in the cell

sacs of digestive enzymes w/ a low pH

• Barrier that defines the border of the cell
• Phospholipid bilayer

cell wall/cell membrane

• cell pool
• main location of a cells biochemical and biosynthetic activities

• permeable to water and small unchanged molecules
• retains metabolites and ions in the cell

• things move down the concentration gradient across the semi permeable membrane
• Ex: water, oxygen, nitrogen, carbon dioxide

• Use of a protein to make a hole in the membrane that will allow molecules to diffuse down the concentration gradient
• Permeases
• Ex: some amino acids, some sugars

Use of protein and energey to move a compound against the concentration gradient across the membrane

moves certain sugars down the concentration gradient while modifying the sugar in an energy dependant way

responsible for cell shape and protection agains osmotic lysis

movement of water across a concentration gradient

exploding or breaking open

• two layers of lipids
• 50% protein, 50% lipid
• fluid
• allows lipids and proteins to move w/in the phospholipid bilayer

Polymer of sugar residues that coat the bacterium or eykaryote

Whip-like structures that allow for rapid movment of the cell

• long rods that stick out from the surface of the cell
• adhesion

• only in Eukaryotes
• propel the cell in a whip-like movement

9 microtubules on the outside and 2 on the inside

movement of an organism towards or away from a chemical

movement to or from light

movement to or from oxygen

movement in a desired direction

actin, microtubules, and intermediate filaments making up the shape of most Eukaryotes

• power house of the cell
• where respiration occurs in Eukaryotes

• part of the nuclear envelope
• location at which membrane proteins can be insterted into the eukaryotic membrane and proteins are secreted out

site of photosynthesis in plant cells

membrane sacs allow for localization of different sets of enzymes that allow spec modifications of the protein

• microtubule organization center of the cell
• 9+0 array

protein sacs that form organelles in bacteria

two

grape like clusters

chains

groups of four cells

groups of eight cells

• Stains with a net + charge
• The cytoplasm of the cell is - charged so the dyes are attracted to the interior of the cell by electrical charge

• negative charged
• same charge as bacteria so not attracted to bacteria
• useful for visualizing the bacteria

allows you to visualize two populations or structures at the same time so you can distinguish them from each other

chemical that fixes a dye in or on cells by forming insoluable compound and promoting retention of the dye

process where subset of cells are destained - dye is washed out

• divides most Eubacteria into either + or -
• important in clincial micro

thick peptidoglycan wall

thin peptidoglycan wall

stain which shows the Mycobacterium and Norcardia

• staining of very heat resistant spores
• Malachite green, steam, water, saphranin

• Similar structure in all Eubacteria
• Archae have pseudo-pep. that has simiiar components but different structure

long suger molecule that is sometimes membrane anchored (lipo-)

• Gram - wall
• Cytoplasmic membrane of the cell

• Gram - wall
• Space between two membranes of the cel
• 1. Peptidoglycan (about 1 layer thick)
• 2. Peri-plasmic proteins
• 3. Brauns lipoprotein -anchors outer membrane to the peptidoglycan

• Gram + wall
• allow the cell to interact with external environment

• Only in Gram - bacteria
• layer containing LPS and Porins

proteins that form larger pores in the outer membrane through which small macromolecules can pass

• lipopolysachharide
• Lipid A - extrememly toxic to animals and can cause septic shock

species specific polysaccharides

• single layer of lipids membrane
• essential to get nutrients across the layer of lipids

• type of sugar attached to peptidoglycan
• very long and allow for the addition of many mycolic acid molecules

• G+ bacteria specific
• No metabolic activity
• Most heat-resistance form of dormancy known

area b/t two membranes that contains the peptidoglycan

dense layer of protein that protects the endospore from toxic chemicals

loose lipid-protein; unknown function

formation of endospores

• External spores
• Several species of Archae form them

Activiation, Germination, Outgrowth

• Formed by some bacteria and some eukaryotes
• Thick walled cells that form when nutrients are exhausted
• Generally resistant to chemicals, drying, and mechanical stress -- not heat resistant