Microbiology; EXAM I

Carbohydrates

"Compound containing carbon, hydrogen, and oxygen in the approximate ratio of 1:2:1 (e.g., sugars, starches, and cellulose)"

Halophiles

"salt-loving" archaea that live in environments that have very high salt concentrations

Gram staining procedure

*Heat Fix* 1. Primary stain- Crystal violet (1 minute) *Wash off stain with di-water* 2. Mordant- Gram's Iodine (1 minute) *Wash off the iodine* 3. Decolorization- Acetone-alcohol (hold slide at 45 degree angle and apply decolorizer, do this until it runs clear) *Stop decolorization by washing slide with gentle stream of di-water* 4.Counterstain- Safranin (1 minute) *Wash off gently for only a few seconds* 5. Blot dry with bibulous paper & air dry 6.Examine slide under oil immersion

What defines a species in bacteria?

*bacteria definition is not the same as animals bc they do not exhibit a typical mode of sexual reproduction* -they can accept genetic information from unrelated forms, and they can alter their genetic makeup by a variety of mechanisms -a collection of bacterial cells that share an overall similar pattern of traits, in contrast to others who differ

OTHER THAN A LACK OF A NUCLEUS, what are two ways in which eukaryotic microbes differ from prokaryotic microbes?

- Eukaryotic cells are much larger in size than prokaryotic cells - Their energy source for flagellar movement is different one is for ATP and the other is by hydrogen ions

Capsule

-(Tan coating) -a coating or layer of molecules external to the cell wall. it serves as protective, adhesive, and receptor functions. it may fit tightly or be very loose and diffuse. Also called slime layer and glycocalyx -outline Advantage: generally greater pathogenicity bc capsules protect the bacteria against white blood cells called phagocytes. phagocytes are a natural body defense that can engulf and destroy foreign cells through phagocytosis, thus preventing infection. a capsular coating blocks the mechanisms that phagocytes use to attack to and engulf bacteria.

Endotoxin

-A toxic component of the outer membrane of certain gram-negative bacteria that is released only when the bacteria die -fever/shock -aka LPS

What is ATP?

-Adenosine Triphosphate - ENERGY - is required for active transport. -A nucleotide containing adenine, ribose, and three phosphates -belongs to a category of high energy compounds that give off energy when a bond is broken between the second and third (outermost) phosphates -> the presence of these high energy bonds makes it possible for ATP to release and store energy for cellular chemical reactions

prokaryotic cell wall

-All prokaryotic cells have a stiff cell wall, located underneath the capsule (if there is one). This structure maintains the cell's shape, protects the cellinterior, and prevents the cell from bursting when it takes up water. -peptidoglycan

what sort of unusual things do Archaea do?

-Archaea can also generate energy differently and have unique ecological roles toplay, such as being responsible for producing biological methane—something no eukaryotes or bacteria can do. -Some archaea obtain energy from inorganic compounds such as sulfur or ammonia (they are chemotrophs). ex: menthogens

What is involved in actually identifying bacteria?

-Bacteria are identified routinely by morphological and biochemical tests, supplemented as needed by specialized tests such as serotyping and antibiotic inhibition patterns. -Newer molecular techniques permit species to be identified by their genetic sequences

How have we "modified" or "loosened" Robert Koch's postulates and why?

-It is difficult to satisfy Koch's postulates for viral diseases because viruses usually have a very narrow host range. -the majority of infections are polymicrobial -> cannot be satisfied -Dr. Stanley Falkows: "molecular Koch's postulates" were formulated to establish that a gene found in a pathogen contributes to the disease-causing ability of the organism -the general idea of Koch's postulates is that you must isolate what you think the cause is, then apply it to a naive population and produce the same effect. mThis general progression is still considered the gold standard for determining that any given factor is causing-not simply correlated with-an observed condition. -it is difficult for true causation to be proven i.e.; Facebook exp ex

Archaea membrane

-Like all other living cells, the archaea cell membrane is made up of phospholipids with fatty acid chains, but the bonds in the archaeaphospholipids are unique. -All cells have a phospholipid bilayer, but in archaea cells, the bilayer has etherbonds while the cells of bacteria and eukaryotes have ester bonds. Ether bonds are more resistant to chemical activity and allow archaea cells to survive in extreme environments that would kill other life forms.

What is lipopolysaccharide (LPS)?

-Major component of the outer membrane of a gram-negative bacteria -uppermost layer of sandwhich -chains function as cell markers and receptors

Describe two phenotypic characteristics that can be used to identify bacteria?

-Motility/shape: P -> rotation flagella E -> wave flagella -Cell Wall which can be identified using a stain because a cell wall has peptidoglycan

prokaryotic cell membrane

-Prokaryotes lack mitochondria and instead produce their ATP on their cell surface membrane which creates a proton gradient -In prokaryotes, the electron transport chain components are found in the plasma membrane. ... Energy is released in these "downhill" electron transfers, and several of the protein complexes use the released energy to pump protons from the mitochondrial matrix to the intermembrane space, forming a proton gradient. -oxidation phosphorylation

solid media

-Provides a firm surface upon which cells can form discrete colonies -use to isolate colonies -easier to see than liquid

Taxonomy

-The formal system for organizing, classifying, and naming living things. -all forms of modern and extinct life

How does normal flora contribute to human health?

-The normal flora prevent colonization by pathogens by competing for attachment sites or for essential nutrients. This is thought to be their most important beneficial effect, which has been demonstrated in the oral cavity, the intestine, the skin, and the vaginal epithelium. -normal flora helps to prevent us becoming colonized with more dangerous bacteria, which might lead to infection.

Phylogeny

-The scheme that represents the natural relatedness (relationship. by descent) between groups of living beings. -used to determine taxonomy -phylogenic tree

what are some examples and functions of nucleic acids?

-Two examples of nucleic acids include deoxyribonucleic acid (better known as DNA) and ribonucleic acid (better known as RNA). These molecules are composed of long strands of nucleotides held together by covalent bonds. Nucleic acids can be found within the nucleus and cytoplasm of our cells. -informational molecules -Nucleic acid is an important class of macromolecules found in all cells and viruses. The functions of nucleic acids have to do with the storage and expression of genetic information. Deoxyribonucleic acid (DNA) encodes the information the cell needs to make proteins.

Why are biofilms important?

-biofilm=microbes attach to solid surfaces (rocks, teeth, medical implants) and grow into masses. They are important because they provide protection for bacteria in the masses -serious medical implications -affinity for medical implantations ex: IUD

Liquid Media

-broth Liquid medium is convenient to use for growing bacteria in test tubes, and can reveal information about the oxygen requirements of bacteria growing within.

What are characteristics of a lipopolysaccharide?

-can act as a toxin -portion of it is a carbohydrate -stabilizes the outer membrane of gram (-) bacteria

similarities between prokaryotic and eukaryotic microbes

-cell membrane -> lipid bilayer -genetic material -> DNA -ribosomes -cytoplasm -both living

Where in the environment, do you find Archaea?

-extremophiles = love extreme conditions -heat, salt, acid, pH, pressure, and atmosphere.

What are some things that have contributed to the decrease in deaths due to infectious disease?

-food production -a nutrient source -drug production -agriculture -cleaning up the environment -decomposition

Microorganisms are important in/as/for...

-genetic engineering -bioremediation -recombinant DNA technology -handling oil spills/restoring stability to the environment -evolution -digest

Microorganisms are important in/as/for...

-genetic engineering -bioremediation -recombinant DNA technology -handling oil spills -> helps restore stability to the environment -hair

Robert Koch (1843-1910)

-he developed a standard for determining causation of a new disease that would stand the test of new scientific scrutinity. -Postulates: 1. find evidence of a particular microbe in each of case or disease 2. isolate that microbe & cultivate it in pre culture in lab 3. inoculate a subseptible healthy subject, isolate and observe disease 4. re-isolate the lab and isolate from this subject

techoic acids

-in gram positive cell wall -is a tightly bound acidic polysaccharide -a polymer of ribitol or glycerol (alcohols) and phosphate that is embedded in the peptidoglycan sheath

How does an oil immersion lens help to improve resolving power?

-it can resolve any cell or cell part as long as it is at least 0.2 micron in diameter -oil immersion is a technique used to increase the resolving power of a microscope. This is achieved by immersing both the objective lensand the specimen in a transparent oil of high refractive index, thereby increasing the numerical aperture of the objective lens.

What is "normal flora"?

-microbes that live on and in body without causing apparent harm -normal flora helps to prevent us becoming colonised with more dangerous bacteria, which might lead to infection.

What are biofilms?

-scum that builds up on your toilet, shower, or even on your teeth -this slimy gunk isn't merely evidence that you haven't cleaned in awhile; it is a community of microbes -microbial habitats with access to water, food atmosphere, and other environmental factors that are beneficial to each type of organism that is living there.

How related to the Archaea and the Eukarya?

-share a number of ribosomal RNA sequences that are not found in bacteria -ribosomal subunits are similar (more towards 80s)

What are some properties of lipids?

-the main group of compounds classified as lipids are triglycerides, phospholipids, steroids, and waxes -Lipids may be either liquids or non-crystalline solids at room temperature. -Pure fats and oils are colourless, odorless, and tasteless. -They are energy rich organic molecules -Insoluble in water -Soluble in organic solvents like alcohol, chloroform, acetone, benzene etc. -No ionic charges -Solid triglycerols (Fats) have high proportions of saturated fatty acids. -Liquid triglycerols (Oils) have high proportions of unsaturated fatty acids.

How are Archaeas membranes different from other organisms?

-unusual and chemically distinct cell walls -> some are composed almost entirely of polysaccharides and in others the walls are pure protein -AS A GROUP... ALL LACK THE PEPTIDOGLYCAN structure -some lack a wall completely

The ph scale ranges from...

0 to 14

What is considered to be an acidic ph?

0-6

Assume that acid rain has lowered the pH of a particular lake to pH 4.0. What is the hydroxyl ion concentration of this lake?

1 × 10-10 mol of hydroxyl ion per liter of lake water

Give two ways in which the Archaea are different from other prokaryotes:

1. Their ribosomal structure is more related to Eukarya, 70s but more similar to 80s like Eukarya 2. They are extremophiles (love extreme conditions)

Koch's postulates

1. find evidence of a particular microbe in each of case or disease 2. isolate that microbe & cultivate it in pre culture in lab 3. inoculate a subseptible healthy subject, isolate and observe disease 4. re-isolate the lab and isolate from this subject

3 Components of peptidoglycan

1. polysaccharide backbone (carbohydrate) 2. tetra peptide side chain 3. peptide cross links

One liter of a solution of pH 2 has how many more hydrogen ions (H+) than 1 L of a solution of pH 6?

10,000 times more

tetrapeptide side chains

4 amino acids attached to NAMs in the backbone

What is considered to be a basic ph?

8-14

Archaeal types

: methanogens, halophiles, and thermophiles.

Describe what a bacterial flagella looks like (it's structure) and contrast with what the flagella looks like in eukaryotic cells

A bacterial flagella is extremely thin and thus requires high magnification to reveal its specialized structure. It is divided into three parts: the filament, the hook (sheath), and the basal body. The eukaryotic flagellum is thicker (by a factor of 10) structurally more complex, and covered by an extension of the cell membrane. I have inserted an image below that further visualizes these differences in structure. As you can see, the eukaryotic flagellum is more in the shape of a cylinder, whereas the prokaryotic flagellum is more "hook" like.

atomic force microscope

A device for mapping surface atomic structure by measuring the force acting on the tip of a sharply pointed wire or other object that is moved over the surface.

Methanogens

A group of archaebacteria that produce methane as a by product of their metabolism.

Scanning Electron Microscope (SEM)

A microscope that uses an electron beam to scan the surface of a sample, coated with metal atoms, to study details of its topography.

Transmission Electron Microscope (TEM)

A microscope that uses an electron beam to study the internal structure of thinly sectioned specimens.

Purines

A nitrogen base that is an important encoding component of DNA and RNA

Monomer

A simple molecule that can be linked by chemical bonds to form larger molecules

What would be an unexpected consequence of changing one amino acid in a protein consisting of 325 amino acids?

A, B, and C are correct.

differential interference contrast

Accentuates diffraction of the light that passes through a specimen; uses two beams of light

Purines of DNA

Adenine (A) and Guanine (G)

What are the four types of bases in DNA?

Adenine (A), Thymine (T), Guanine (G), Cytosine (C)

Which of the following is NOT true of endospores? -All gram + bacteria produce them -Produced in response to low nutrients -Are very heat resistant -contain very little wate

All gram + bacteria produce them

differential media

Allow multiple types of microorganisms to grow, but display visible differences between colonies ex: -blood agar -MSA agar

A selective media is one in which:

An agent is used to inhibit the growth of many microbes

Domain: high-salt loving microbes

Archaea

Domain: methanogens

Archaea

Domain: thermophiles

Archaea

Thermophiles

Archaea that thrive in very hot environments, such as volcanic springs.

Domain: E. Coli

Bacteria

Domain: Spirillum volutans

Bacteria

Domain: Staphylococcus aureus

Bacteria

Domain: bacillus anthracis

Bacteria

Domain: cyanobacteria

Bacteria

Domain: spirochetes

Bacteria

Domain: streptococcus sp.

Bacteria

Domain: vibrio cholerae

Bacteria

Describe how bacterial cells move (how the whole cell moves) as a result of bacterial flagella rotation.

Bacteria use their flagella in an ingenious way. The flagellum is effective in guiding bacteria through the environment primarily because the system for detecting chemicals is linked to the mechanisms that drive the flagellum. Located in the cytoplasm are receptors that in groups can transmits signals to the flagellum and sets them into rotary motion. However, the actual motivation to move comes from a gradient of protons (hydrogen ions) that are generated by the metabolism of the bacterium and that bind to and detach from parts of the flagellar motor within the cytoplasmic membrane, causing the filament to rotate. If there is more than one, they rotate together as a group. As it or they rotate counterclockwise, the cell itself swims in a smooth linear direction toward the stimulus. This action is called a run. Runs are interrupted variously by tumbles. A tumble is where the flagellum reverses direction and causes the call to stop and change its course. Alternation between both runs and tumbles is known as a "random walk", a form of motility in these bacteria.

Domain system:

Bacteria, Archaea, Eukarya

peptidoglycan consists of which two types of organic molecules?

Carbohydrates and protein

Cocci bacteria bacteria arranged in to a sarcina will look like?

Cells arranged in cubes of 8 cells

What is chemotaxis?

Chemotaxis is the movement of an organism in response to a chemical stimulus. Somatic cells, bacteria, and other single-cell or multicellular organisms direct their movements according to certain chemicals in their environment. Moreover, Flagellated bacteria can detect and move in response to these chemical signals.

The ribosomes in ______ and _____ are identical to the size seen in bacteria.

Chloroplasts; Mitochondria

A media made from a tryptic digest of soybeans and a chemical that changes color only in the presence of a specific species would be considered a ____ & ___media.

Complex and Differential

What gives the bacteria cell wall it's strength?

Cross- Links between the side chains of peptidoglycan

Pyrimidines of DNA

Cytosine (C) and Thymine (T) -> Uracil (U)

polymer of nucleic acids

DNA and RNA

Which of the following best describes the flow of information in eukaryotic cells?

DNA → RNA → proteins

Antonie von Leeuwenhoek (1673)

Dutch merchant/scientist, 1st person to see bacteria, yeast "Father of Microbio/ Protozoology" (~250x magnification). Self made microbiologist, contributed a small powerful microscope with the ability to see up to 300x magnification, created refined lenses, condensor & built in light

Which of the following is NOT a real difference between the flagella of bacteria (prokaryotic) and the flagella of eukaryotic cells? (refer to Ch. 4 and Ch. 5 to help answer this) -Euk flagella are involved in chemotaxis, Prok flagella are involved in attachmen -Euk flagella have microtubules, Prok do not - Prok flagella rotate, Euk move in a wave-like pattern -Euk flagella are covered by a membrane, Prok are not

Euk flagella are involved in chemotaxis, Prok flagella are involved in attachment

Domain: Penicillium mold

Eukarya

Domain: Psilocybin mushrooms

Eukarya

Domain: euglena

Eukarya

Domain: lice

Eukarya

Domain: planaria

Eukarya

Domain: tapeworms

Eukarya

Domain: the protozoan that causes malaria

Eukarya

Domain: yeast

Eukarya

Endosymbiosis is a process that led to the development of ___________ cells.

Eukaryotic

Which type of light microscopy would be good for tracking a protein through a cell?

Fluorescence

difference between gram positive and gram negative cell wall

Gram negative has a thin peptidoglycan layer, lipopolysaccharides, double membrane gram positive has a thick layer of peptidoglycan, single membrane

Louis Pasteur (1822-1895)

He filled flasks with broth & fashioned there openings into a long, swan shaped neck. Gravity would deposit contaminents into the neck. Then, he sterilized the flasks and intubated them. Thus, as long as the neck was intact, then no microbes grew. Vice versa. = debunked Theory of spontaneous generation

ph Scale

In chemistry, pH is a scale used to specify how acidic or basic a water-based solution is. Acidic solutions have a lower pH, while basic solutions have a higher pH.

What type of cells have periplasmic flagella? How do these cells move?

In spirochetes, the organelles for motility, the periplasmic flagella, reside inside the cell within the periplasmic space. A given periplasmic flagellum is attached only at one end of the cell, and depending on the species, may or may not overlap in the center of the cell with those attached at the other end. I have inserted an image below that further visualizes and explains the motility of periplasmic flagella.

A 20-year old college student reports to the school's health center complaining of headache and stiffness in the neck and shoulders. He has a fever of 101 F.What is the first thing you do with the spinal tap?

Inoculate it on to media

What are the 5 I's?

Inoculation Incubation Isolation Inspection Identification

Which of the following is not a characteristic of lipopolysaccharide (LPS)?

It is a component of peptidoglycan

Which scientist was responsible for establishing that Bacillus anthracis caused Anthrax?

Koch

Which scientist was the first to see microbes?

Leuwenhoek

The portion of the gram negative cell wall that can act as to stimulate fever and septic shock is called ________.

Lipopolysaccharide

What describes the movement of bacteria during chemotaxis?

Longer 'runs' and tumbles toward attractant

How did Louis Pasteur disprove/debunk spontaneous generation?

Louis Pasteur is credited with conclusively disproving the theory of spontaneous generation with his famous swan-neck flask experiment. He subsequently proposed that "life only comes from life."

Why do microbiologists classify organisms?

Microbiologists like to classify things because... -helps us organize -helps us to understand relationships -helps us to understand evolution ...taxonomy ...phylogeny ...phylogenic trees

polysaccharide back bone

NAG = N-acetyl muramic acid NAM = acetyl glucosamine acid

Pyrimidines

Nitrogen bases that that can help form the genetic code on DNA and RNA

Domain: The microbe that causes aids...

No domain

Domain: the microbe that causes influenza

No domain

Domain: the microbe that causes rabies

No domain

The microbe that causes ... = ?

No domain

Domain: ebola

No domain ***

Proteins

Nutrients the body uses to build and maintain its cells and tissues

Study 5 I's

PAGE 54

Gram (-) bacteria have a thin layer of ____________ between two layers of membrane.

Peptidoglycan

Mycoplasma pneumoniae lacks...

Peptidoglycan

what type of microscopy can be used to view organelles in Euk. Cells without using stains?

Phase contrast

Crystal Violet

Primary stain, stains both gram-positive and gram-negative cells purple.

Gram Staining Results

Purple: Positive Pink: Negative

Prokaryotic and Eukaryotic cells both have these structures. However, they are differently sized in each. They are sites where proteins are made. They are called _______________.

Ribosomes

Bacillus

Rod shaped bacteria

To achieve isolation of microorganisms you would want to inoculate the organisms on to ____________ media.

Solid

Decolorizer

Solubilizes lipids in outer membrane, solubilizes the crystal violet from gram -, gram - colorless, gram + still purple,

Cocci bacteria that undergo division in several intersecting planes are referred to as

Staphylococci

If microbe is an acidophile (loves acid) it would likely prefer to grow at?

The Lowest ph; ph 5

How are the bacteria found in the biofilm different than in a single celled form?

The microbial cells growing in a biofilm are physiologically distinct from planktonic cells of the same organism, which, by contrast, are single-cellsthat may float or swim in a liquid medium. Biofilmscan form on the teeth of most animals as dental plaque, where they may cause tooth decay and gum disease.

What is true of both starch and cellulose?

They are both polymers of glucose.

Compare how bacterial flagella move with how eukaryotic flagella and cilia move (this is not how the whole cell moves, but how the flagella actually moves).

Though eukaryotic flagella and motile cilia are ultrastructurally identical, the beating pattern of the two organelles can be different. In the case of flagella, the motion is often planar and wave-like, whereas the motile cilia often perform a more complicated three-dimensional motion with a power and recovery stroke.

dark field microscopy

a form of microscopy in which the specimen is brightly illuminated on a dark background

confocal microscopy

a light microscope that uses fluorescent stains and laser to make two- and three-dimensional images

Polymer

a macromolecule made up of a chain of repeating units. Examples: starch, protein, DNA

Which of the following descriptions best fits the class of molecules known as nucleotides?

a nitrogenous base, a phosphate group, and a pentose sugar

A given solution contains 0.0001(10-4) moles of hydrogen ions [H+] per liter. Which of the following best describes this solution?

acidic: H+ donor

Match the bacterial cell structure on the left with its primary function on the right: Fimbriae

adhesion

monomer of proteins

amino acids

Pili (pilus)

an appendage used for drawing another bacterium close in order to transfer DNA to it -side straw Advantage: DNA transfer

Polysaccharides, lipids, and proteins are similar in that they

are synthesized from monomers by dehydration reactions.

Understand the relative size differences between eukaryotic cells, bacteria, and viruses

biggest to smallest -eukaryotic cells -bacteria cells -viruses

How do biofilms form?

biofilms can form on numerous inert substances, usually when the surface is moistened has developed a thin layer of organic material, such as polysaccharides or glycoproteins. this slightly sticky texture attracts the first single-celled "colonists" that attach and begin to multiply on the surface

Match the bacterial cell structure on the left with its primary function on the right: Capsule

blocks phagocytosis by white blood cells

What 'environments' is devoid of microbes (sterile)?

blood

Which prokaryotic-specific structure prevents bacteria from being recognized and engulfed by the immune system?

capsule

strepto

chains

Match the bacterial cell structure on the left with its primary function on the right: Flagella

chemotaxis

The flagella in bacteria would be critical in carrying out which of these functions?

chemotaxis

All of the following contain amino acids except: antibodies. hemoglobin. insulin. enzymes. cholesterol.

cholesterol

Media created from an extract of sheep kidneys would best be classified as a ______ media.

complex

Which type of media would be used for culturing and isolating as many organisms as possible from soil?

complex

Which of the following is NOT true of prokaryotic cells?

contain membrane-bound organelles

complex media aka undefined media

contain some ingredients of unknown composition and/or concentration -ex: TSA

selective media

contains one or more agents that inhibit growth of a certain microbe or microbes, but not others, encouraging that selected to grow ex: -PEA agar -MSA agar

sarcoma

cubical packet

Most important step in differentiating in gram staining

decolorizer

Type of media where all components are known.

defined

The function of each protein is a consequence of its specific shape. What is the term used for a change in a protein's three-dimensional shape or conformation due to disruption of hydrogen bonds, disulfide bridges, or ionic bonds?

denaturation

This type of microscopy is needed to view virus structure.

electron

What are lipids?

fat -> term for a variety of substances that are not soluble in polar solvents such as water, but will dissolve in nonpolar solvents such as benzene and chloroform

Fimbriae

fine, hairlike bristles extending from the cell surface that help in adhesion to other cells and surfaces Advantage: bacterial conjugation, enhance pathogenicity

Prokaryotic External Features

glycocalyx, cell wall, cell membrane

if you decrease the [H+] by 10 fold the ph of the solution will

go by up 1 unit

staphylo

grape-like clusters

tetrad

groups of four

In the double helix structure of nucleic acids, cytosine hydrogen bonds to

guanine

Gram's iodine

helps crystal violet stain form complexes with peptidoglycan (cell wall)

Match the staining reagent on the left to its function in the gram stain: Grams Iodine

helps primary stain form primary complexes within peptidoglycan

Humans can digest starch but not cellulose because

humans have enzymes that can hydrolyze the alpha (α) glycosidic linkages of starch but not the beta (β) glycosidic linkages of cellulose.

Match the microbial structure on the left to the function on the right: Sexual spores

increases genetic diversity of fungi

After incoulating microbes on to sterile media what is the next logical step in the culturing process?

incubation

How was the phylogenic tree made?

it is based on evolution and is the idea that all life is related by common descent. It was developed by looking at similar ssuRNA to show rekationships

Peptidoglycan consist of all of the following EXCEPT.... lipopolysaccharide polsaccharide backbone tetrapeptide side chains peptide cross-link

lipopolysaccharide

nucleic acids

macromolecules containing hydrogen, oxygen, nitrogen, carbon, and phosphorus

Microorganisms ->

many types, many places, many sizes = diversity

The correct term for single celled microscopic beings is:

microorganisms

Scanning Tunneling Microscope (STM)

microscope that measures electrons that leak or "tunnel" from the surface of the specimen

S-layer

monolayer of protein used for protection and/or attachment -chz grater Advantage: the armour

Which of the these molecules represents the best quick energy source for bacteria?

monosaccharides

monomer of carbohydrates

monosaccharides -> (glucose, fructose, galactose)

branching filaments

multiple branches off a basic rod structure

Hydrophobic substances such as vegetable oil are

nonpolar substances that repel water molecules.

monomer of nucleic acids

nucleotides

Match the staining reagent on the left to its function in the gram stain: Safranin

only effectively stains gram - cells

What is the pH of a solution with a hydroxyl ion [OH-] concentration of 10-12M?

pH 2 (I think this is supposed to be 12?)

What is the pH of a solution with a hydrogen ion [H+] concentration of 10-8M?

pH 8

What is a neutral ph?

pH of 7

This type of microscopy would likely be the best for observing the nuclei in unstained preparations of eukaryotic microorganisms?

phase contrast microscopy

In bacteria, microbes that can exhibit multiple cellular morphologies are referred to as being _________.

pleomorphic

Phospholipids consist of (an) ______________, a phosphate functional group and two fatty acid tails

polar head group

polymer of proteins

polypeptide

polymer of carbohydrates

polysaccharide (starch, glycogen, cellulose)

defined media

precise chemical composition is known -ex: blood agar

Match the staining reagent on the left to its function in the gram stain: Crystal violet

primary stain, stains both gram + and gram -

Match the microbial structure on the left to the function on the right: Asexual spores

produced by mitosis, will generate genetically identical fungi

bright field microscopy

produces an image made from light that is transmitted through a specimen

peptide cross-links

provide a strong, but flexible framework

The nitrogen containing SINGLE ring structures in nucleic acids are called:

pyrimidines

Media that contains chemicals that will inhibit all bacteria except for a few types is called _______ media.

selective

diplo

single pairs

Spirillum

slightly curled or spiral-shaped cylinder

vibrio

slightly curled or spiral-shaped cylinder

Match the staining reagent on the left to its function in the gram stain: Alcohol

solubilizes lipids in outer membrane, solubilizes primary stain from gram -

Coccus

spherical or ball-shaped

Spirochete

spiral cell, a more flexible form that resembles a spring

Safranin

stains only gram - cells gives them color so you can identify bacteria = pink

Match the microbial structure on the left to the function on the right: Endospores

survival structure in bacteria

if I am increasing the H+ then I am decreasing the ph....& view versa

ten fold - 10^1 hundred fold - 10^2

resolving power

the capacity of a microscope lens system to accurately distinguish between two separate entities that lie close to eachother -also called resolution

What are the two characteristics that contribute to a microscope lens having good resolving power?

the lenses ability to gather light and the wavelength of light

How else are archaea different from other organisms?

their ability to live in extremely hot or chemically aggressive environments, and they can be found across the Earth, wherever bacteria survive.

Lipids are grouped together because...

they are all hydrophobic

Which of the following is NOT true of gram negative bacteria?

thick layer of peptidoglycan in cell wall

What is a "strain"?

to designate bacteria of the same species that have different characteristics

Match the bacterial cell structure on the left with its primary function on the right: Pilus

transfer of DNA from cell to cell

phase contrast

transforms subtle changes in light waves passing through the specimen into differences in light intensity, best for observing intracellular structures

fluorescence microscopy

uses a fluorescent dye that emits fluorescence when illuminated with ultraviolet radiation

These are unicellular fungi that reproduce asexually, but can sometimes stay attached to form pseudohyphae

yeasts

prokaryotic cell membrane

•Referred to as phospholipid bilayer; composed of lipids and associated proteins •Approximately half the membrane is composed of proteins that act as recognition proteins, enzymes, receptors, carriers, or channels -Integral proteins -Peripheral proteins -Glycoproteins •Fluid mosaic model describes current understanding of membrane structure