BYU MMBio 221 exam 1 Robison

Obligate halophiles

High osmotic pressure aka lots of salt like the great salt lake

Bacteria cell walls are made of

peptidoglycan (NAG and NAM)

Gram Positive

-unique polysaccharides called teichoic

-thick layer of peptidoglycan

-purple

Acid fast

-mycloic acids

-wax like

-Peptidoglycan and porins

Gram Negative

-LPS called endotoxin

-outer bilayer of membrane composed of phospholipids, channel proteins(porins) and LPS

-thin layer of peptidoglycan

-pink

pili

long hollow tubes

-longer than fimbraea but shorter than flagella

-grappling gooks

-join two bacteria to transfer DNA

Fimbriae

sticky bristle-like

-used to adhere to one another

attachment in biofilms

Mycoplasma

a bacteria that lacks a cell wall entirely

Archaea Cell Walls

-composed of proteins or polysaccharides NOT peptidoglycan

-Gram neg cells have outer protein layer rather than lipid bilayer

-strange shapes

Archaea have

cytoplasmic membranes

-ethers

-branched hydrocarbons

In a hypertonic solution

crenation

in a hypotonic solution

grows and swells

Plasmolysis

when a cell wall is in hypotonic

fungi cell walls are made out of

chitin

Metric units

Meter, cent (100), milla (1000), Micro (move . 6x), nano (move 9x)

periplasmic space

between outer membrane and plasma membrane

-peptidoglycan and periplasm

-proton place

-contains nutrients and substance

Confocal Microscope

Also uses fluorescent dyes

Use UV lasers to illuminate fluorescent chemicals in a single plane that is no thicker than 1.0 μm

Resolution increased by up to 40% because emitted light passes through pinhole aperture

Computer constructs 3-D image from digitized images

are all cells naturally fluorescent?

No some require staining to see on fluorescent microscopes

Fluorescent Microscopes

Direct UV light source at specimen; fluorochromes absorb the UV light and radiate energy back as a longer, visible wavelength

UV light increases resolution and contrast

Two types of Phase Microscopes

Phase-Contrast Microscope

Differential Interference Contrast (DIC) Microscope

Phase Microscopes

Used to examine LIVING organisms or specimens that would be damaged or altered by attaching them to slides or staining them

These microscopes treat one set of light rays differently from another set

Light rays IN PHASE produce BRIGHTER image,

while light rays OUT of PHASE produce DARKER image

Contrast is created because light waves are ½ wavelength out of phase

Dark-Field Microscopes

- Best for observing pale or very thin objects that are LIVING

Only those oblique light rays scattered by specimen enter objective lens

Specimen appears light against dark background

Increases contrast and enables observation of thin and translucent orgs

total magnification equals?

magnification of objective lens X magnification of ocular lens

Oil immersion lens

increases resolution because light does not refract

compound bright field microscope

- Uses a series of lenses for magnification

-Light rays pass through specimen and into objective lens (one of a series)

-Has one or two ocular lenses

-Most have condenser lens to direct light through specimen

Numerical apertures

10X-.30

40X-.75

100X- 1.30

Properties of magnification

refracts light and magnetic fields act as a lens to refract electron beams

Resolution depends on...

1) The wavelength of the electromagnetic radiation 2)the numerical aperture of the lens (1/2)

simple bright field microscope

-Contains a single magnifying lens

-Similar to magnifying glass

-Leeuwenhoek used simple microscope to observe microorganisms

Bright-Field Microscopes:

two types

Simple

Compound

Bright-Field Microscopes are most frequently used on what specimens?

Stained specimens

Light Microscopy types

1. Bright-field microscopes

2. Dark-field microscopes

3. Phase microscopes

4. Fluorescent microscopes

Confocal microscope

Limits of resolution

STM (.01nm - 10nm)

TEM (.078 nm - 100um)

SEM (.4nm - 1mm)

AFM (1nm - 10nm)

light microscope (200nm- 10mm)

human eye (200um - )

Refraction

change in direction of wave propagation due to a chnge in its transmission medium

Negative stain

Uses acidic dye to leave background stained and specimen colorless

Facultative halophiles

They don't require salt concentration but can tolerate it

Neutrophiles

Most bacteria Protozoa and pathogens like neutral ph rang 6.5-7.5

Acidophiles

Really acidic as low as 0 pH

Alkalineophiles

Grow best in basic range up to 11.5 ex cholera

TEM

the cell has to be sliced to very thin sections to let electrons penetrate.

-cannot be used to study living organisms

SEM

whole specimens can be seen

-must be a dead organism

-only external surface though

Thermophiles

Higher temperatures above 45C ex hot springs

Hyperthermophiles

Hottest 80C and above

Mesophiles

Room temperature 20-40C

Psychrophiles

Super cold 15-below 0C

Barophiles

High pressures

Obligate barophiles

Super duper high pressures like deep sea trenches

Microaerophiles

Low oxygen levels

Capnophiles

High CO2 and low oxygen

Glycocalyx

Sticky stuff made of polysaccharides or proteins that surround the outside of a cell

Two major types of Glycocalyx

Capsule and slime layer

Teichoic acids

Greek word for wall

Polyalcohols with gram positive cell walls

Lipopolysaccharide

(3 things)

*Aka endotoxin

*Found only in the outer membrane of gram negative cells

*lipid A is the active component

Peptidoglycan

Cell wall of bacteria

Composed of alternating units of NAG NAM ( N-acetylglucosoamine and N-acetylmuric acid) linked my amino acids

Filament hook rod and rings are associated with:

The bacterial flagellum

Group translocation

Glucose actively enters the cell and is modified simultaneously modified to glucose-6-phosphate

Endosymbiosis theory explains that what two organelles are semiautonomous?

Mitochondria and chloroplasts

Mordant

does not add color itself but binds to a dye making the dye less soluble and more likely to be attached to cellular materials (used in gram stain)

A peritirchously motile bacteria is moving toward attractants, it will

Tumble less

Run more

Hypotonic

Cell gains water and bursts

Cell wall with most Peptidoglycan?

Gram positive

Special stains (2)

Negative (capsule) stain

Flagellar stain

Endospore Stain

uses heat to drive the primary stain malachite green into the endospore and red colored vegetative cells

He classified life by studying RNA.

Says all life =3 domains (eukarya, bacteria, archaea)

Carl Woese

Histological Stains

GMS and HE

Agglutination

Group of microorganisms collect into clumps in response to specific antibodies

Serological

An agglutination test using an antibody to identify a bacterium

Electron microscopes beat light microscopes resolution because

Elections have shorter wavelength than visible light

Fluorescence microscopy uses

*Fluorescein isothiocyanate

*Auramine O

Hydrolases

Hydrolysis of polymers

Allosteric inhibitors of enzymes are also

Noncompetitive inhibitors

Isomerases

rearrange atoms in a molecule

Ligases or polymerases

Join molecules

Oxidoreductases

remove or add electrons

Lyases

split molecules without adding water

apoenzymes

inactive if not bound to non-protein cofactors

cofactors

inorganic ions or organic molecules called coenzymes

Superoxide radicals are detoxified by...

superoxide dismutase

holoenzyme

when an apoenzyme binds to its cofactor

transferases

transfer functional groups

Electron transport chain

H+ in carriers enter a proton gradient that can make ATP by oxidative phosphorylation

Involves cytochrome proteins

Glycolysis

ATP is made by substrate level phosphorylation only

No oxygen used

NADH and pyruvate are produced

Protozoa

categorized by locomotive structures

-flagella made of tubulin

-not rigid corkscrew flagella like prokaryotes

Krebs Cycle

Acetyl-CoA harvested on NADH and FADH2

CO2 is produced

NADH and FADH2

Hydrogen atom carriers

Beta oxidation

Fatty acids in fats are broken down two Carbons at a time

Forms Acetyl-CoA NADH and FADH2

Fungi (mold/ yeast)

-Classified by sexual spore

-Eukaryotic

-Cell walls made of chitin

-obtain food from other organisms

Ex: ringworm, pneumonia, mold, yeast, penicillin DERMATOPHYTOSES

Mold

Fungi that is multicellular reproduce sexual and asexual spores

Yeasts

Fungi that is unicellular

reproduce asexually by budding and spores

Protozoa

Classified by mechanism of motility

Single celled eukaryotes

Sexual and asexual

Use pseudopodia, cilia, and or flagella locomotive

ex.) paramecium, MALARIA, ABEBIASIS, african sleeping sickness, cryptosporidium

Non motile protozoa which cause disease

Plasmodium

Toxoplasma

Cryptosporidium

pseudopodia

Cell extentions that flow in direction of travel

Cilia

Hair propellers

Flagella

Fewer and longer and whiplike than cilia

Algae

-Categorized on basis of pigmentation, storage products, and composition of cell wall

-Uni/multi cellular

-Photosynthetic

-Cell walls

Non pathogenic (except for shellfish poisoning and red tides)

Bacteria

-Prokaryote asexual

-Peptidoglycan cell well moisture

-smaller than eukaryotes

TB, DIPHTHERIA

Virus

Complex replicates inside host and bases its stuff on the host so hard to kill

Can cross a membrane:

H20, small stuff like O2 and lipids

4 transport mechanisms

Diffusion

Facilitated diffusion

Osmosis

Active transport

Diffusion

Movement of a molecule down its concentration gradient