Micro Quiz 1; Chapters 1-4

microorganisms

minute living things that are too small to be seen with normal vision

pathogenic microbes

microorganisms that cause disease

what are the seven microbe roles?

- decompose wastes and recycle nitrogen from air (for other organisms to then use)

- perform photosynthesis

- part of microbiota (protection, aid in digestion)

- produce industrial chemicals

- produce fermented foods

- produce manufacturing and drug products

- biofuel production

cyanobacteria

Bacteria that can carry out photosynthesis

what are microbes organized into?

domains and kingdoms

what is in domains?

bacteria, archaea, and eukaryo

what is in kingdoms?

prokaryotes (bacteria and archaea), fungi, Protista (protozoa), and eukaryotes (algae and animalia)

Prions

misfolded proteins capable of causing normal proteins to become misfolded, cannot be denatured

what disease represents infectious prions?

mad cow disease

endospores

dormant cells formed by certain species of bacteria; resistant to damage and can survive conditions that kill bacteria

Who came up with scientific nomenclature?

Linnaeus

Bacteriology

study of bacteria

Mycology

study of fungi

Parasitology

study of protozoa and parasitic worms

Immunology

study of immunity

Virology

study of viruses

Microbial genetics

study of microbial inheritance

Molecular Biology

studies the chemical basis of life

Matter

Anything that has mass and takes up volume

elements

atoms that share the same physical and chemical properties

ions

Charged atoms (cation and anion)

ionic bonds

ions of opposite charge

covalent bonds

atoms shared pairs of electrons

inorganic compounds

Compounds that do not contain carbon (H2O,NaCl)

organic compounds

Compounds that contain carbon and hydrogen

what do organic compounds contain

macromolecules (polymers)

dehydration synthesis

Condensation reaction where molecules are connected by loss of a water molecule (monomers combine)

hydrolysis

A chemical process that splits a molecule by adding water (polymers are broken down)

What are the monomers of carbs, lipids, nucleic acids, and proteins?

- monosaccharides

- fatty acids

- nucleotides

- amino acids

carbs

- carbon, hydrogen, oxygen

- provide cells with a ready source of energy

- monosaccharide is small carb

what are the important polymers

starch, glycogen, and cellulose

lipids

- carbon, hydrogen, and oxygen

- non polar, hydrophobic

- key components of cell membranes and have long-term storage

- steroids

saturated vs unsaturated

sat: no double bonds

unsat: one or more double bonds

proteins

-workhorse molecules of the cell

- polypeptide is the single protein strand

- sequence of amino acid determines function

denaturation

when proteins are exposed to hostile environments and lose their shape (and function)

nucleic acids

- macromolecules responsible for inheritance in organisms

- DNA & RNA

DNA vs. RNA

DNA: nucleic acid responsible for inheritance in most organisms

RNA: used as heritable material, used to mediate translation of DNA into protein

Resolution

ability of a lens to distinguish between two points

limit of resolution/resolving power

measurement of how far apart 2 points must be to see them as seperate

ex: a microscope with a resolving power of 0.4 um can distinguish between two points >0.4 um

true or false: shorter wavelengths of light provide better resolution

true

NA (numerical aperture)

measure of how much light a lens can capture

- larger NA means better resolution

Brightfield Light Microscopy

Dark objects are visible against a bright background

Darkfield Light Microscopy

Light objects are visible against a dark background

Phase-Contrast Light Microscopy

Direct light and indirect light are combined to show greater differentiation of internal structures

Fluorescence Microscopy

absorb UV light and emit longer wavelength light; cells are directly stained with fluorescent dyes

Transmission Electron Microscopy (TEM)

thin section of fixed sample, can see internal structures

Scanning Electron Microscopy (SEM)

electrons hit surface of sample, deflected off, can create 3D image

Prokaryotes

single celled organisms divided into bacteria and archaea

- no nucleus, DNA is circular, no membrane-bound organelles

Bacteria

cell wall made of peptidoglycan (murein)

Peptidoglycan

a protein-carbohydrate compound that makes the cell walls of bacteria rigid (sugar complex)

Archaea

does not contain murein

Shapes of:

Coccus

Bacillus

Spiral

- berries

- rod-shaped staffs

- vibrio (curved rods), spirillum (fairly rigid corkscrew), and spirochete (flexible corkscrew)

Spirillum

Spirochete

- move with help of flagella

- move by flexible axial filaments wound around the cell

What determines cell arrangement?

plane of division and whether they stay attached after division

Bacilli

1 plane of division possible

Cocci

multiple planes of division possible

Flagella

long, propel bacteria

- cells are described by flagella

Flagella Types:

- atrichous

- peritrichous

- polar

-- monotrichious, lophotrichous, and amphitrichous

- no flagella

- flagella all over cell

- at one or both ends of the cell

-- single flagellum from one pole

-- tuft of flagella from one pole

-- flagella at both poles

Fimbriae

extensions dedicated to attachment of the cell to other surfaces

- shorter and straighter than flagellum

Pili

extensions dedicated to movement and DNA transfer

- usually has one or two pili

sex pilus

DNA is transferred from one cell to another through a sex pilus (can exchange DNA, share antibiotic resistance genes)

Glycocalyx "sugar coat"

a layer of material surrounding the cell wall, containing sticky carbs

capsule

a glycocalyx that is organized and firmly anchored to the cell wall

slime layer

a glycocalyx that is disorganized and only loosely anchored to the cell wall

gram-positive cell wall

stained purple in gram staining

- contain many layers of peptidoglycan

- penicillin only works on this type of staining

gram-negative cell wall

stained red in gram staining

- contain a thin layer of peptidoglycan attached to an outer membrane

- the outer membrane assists the cell in evading immune responses

periplasm

the region between the plasma membrane and the outer membrane

acid-fast cell wall

found in mycobacterium species and pathogenic nocardia species

- cell walls contain mycolic acid, a waxy lipid that prevents most dyes from penetrating the wall

carbolfuchsin

stains bacteria with acid fast cell walls red

phospholipid bilayer

hydrophilic(head) end and hydrophobic(tails) end

The Fluid Mosaic Model

the plasma membrane is not a static or uniform structure and describes the ever-changing heterogeneous properties of the plasma membrane

- proteins, lipids, glycoproteins, and glycolipids move freely through the phospholipid bilayer

selective permeability

allow certain substance to pass more easily than others

- lipid-soluble, uncharged molecules are able to pass through; water soluble can't

concentration gradient

a difference in the concentration of a chemical between two separate areas

- high to low conc.

electrical gradient

diff in the electrical charges between two separate areas

- an electrical gradient that occurs across the plasma membrane is called a membrane potential

diffusion

a process in which particles spread evenly in an available space

- diffuse down their concentration gradient

simple vs. facilitated diffusion

simple: diffusion of particles across a plasma membrane (O2 and CO2)

facilitated: diffusion of polar or charged solutes through a plasma membrane

- channel: solutes flow through the membrane through channel proteins

- carrier: solutes are transported across the membrane by carrier protieins

osmosis

area of high water concentration to an area of low water concentration

aquaporins

transporters that allow water to move across membranes

active transport

cell transports molecules against their concentration gradient though energy

- requires transporter protein

cytoplasm

inside plasma membrane

- ribosomes: perform protein synthesis

- bacterial chromosome and plasmids contain the genetic material

inclusions

deposits of nutrients and substances in the cytoplasm

sporulation vs. germination

- endospore formation; induced by starvation

- return to vegetative state; triggered damage to endospore coat

NOT a form of reproduction

Eukaryotes

single celled or multi celled organisms with internal membranes

- algae, fungi, and protists

- flagella & cilia

- membrane-bound organelles

flagella and cilia in eukaryotic cells

flagella: allow eukaryotic cells to move

cilia: can allow eukaryotes to move, or to push fluid around

cytoskeleton

internal structure of eukaryotic cytoplasm

cytoplasmic streaming

eukaryotic cytoplasm constantly moves around the cell

nucleus

contains most of the hereditary information of the cell

- stored as DNA, in the form of chromatin(DNA wrapped around histone proteins)(visible as chromosomes)

- surrounded by nuclear envelope (nuclear pores, nucleoli (synthesize ribosomes)

ER

molecular synthesis and ion storage

- smooth ER: makes lipids

- rough ER: makes proteins

Golgi Complex

packages and finishes the products of ER

Mitochondria

generates energy catabolism or breakdown of organic molecules

peroxisomes

contain enzymes to digest specific substances

lysosomes

formed from golgi complex, contain powerful digestive enzymes

vacuoles

act as storage spaces for water and other substances

chloroplasts

carry out anabolism, using energy from light

centrosomes

play key roles in cell division and cytoskeleton maintenance