Midterm-Microbiology

Reactions in which molecules are degraded and energy is released are best termed _____. a) anabolic b) catabolic c) metabolic d) exerbolic

B

Antibiosis

"against life"

Halophiles

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

Human immunodeficiency virus has ____ genome, and it utilizes ____ for mRNA transcription.

(+) ssRNA ..... DNA-dependent RNA polimerase

Viruses classified into Baltimore Group 6 have genome made of ____ . Their genome replication depends on ____ .

(+) ssRNA ..... RNA-dependent DNA polynerase + DNA-dependent DNA polymerase

Viruses classified into Baltimore Group 4 have genome made of ____ . Their mRNA transcription depends on ____ .

(+) ssRNA ..... RNA-dependent RNA polymerase

Rabies viruses replication involves ____ intermediate. It is a Baltimore group 5 virus classified to the ____ family.

(+) ssRNA ..... Rhabdoviridae

Viruses classified into Baltimore Group 5 have genome made of ____ . Their genome replication depends on ____ .

(-) ssRNA ..... RNA-dependent RNA polymerase

fluke

(refer to diagram on page 328) Worms mate and lay eggs in hepatic portal blood vessels. Male worms holds female within cleft in his body. Fertilized eggs leave intestinal wall and pass to outside in feces. Eggs hatch in water, free swimming miracidium enters snail (alternate host) and develops into a sporocyst. Sporocyst develops into cercaria and are released into water. Cecarcia enter the body, lose their tails and encyst as metacercaria. Maturation into adult work occurs and cycle repeats.

tapeworm

(refer to diagram on page 329) Cysticerci, bladder worms, are ingested in rare or undercooked meat. Adult worms attaches to mucosa of small intestine. New proglottids form immediately behind the scolex. Old proglottids break off at the far end of the worm. Eggs are passed in feces along with egg-filled proglottid. Feces disintegrate leaving eggs on gras. Cows become infected when it eats contaminated grass. Eggs hatch; larvae burrow through the intestinal wall, enter bloodstream, and encyst in muscles as cysticerci. Cysticercus is infective embryo in meat. Cycle repeats.

adult roundworm

(refer to diagram on page 330) Encysted work in pork. Human ingests cyst in undercooked pork. Stomach acid dissolves cyst cover releasing worms. Females release larvae into lacteals and vessels. Larvae migrate to muscle and encyst. Cycle repeats.

guinea worm

(refer to diagram on page 331) Copepod is digested releasing viable worm. After release, juvenile worm penetrates into the duodenum. After penetrating the duodenum, the worm molts and migrates to the subcutaneous areas of the distal extremities. Gravid female causes blister formation in skin, and upon exposure to water, releases fully formed embryos into the water. Free swimming larvae are ingested by copepods, where they develop into juvenile worms. Copepods containing infective juveniles are consumed in the drinking water. Cycle repeats.

roundworm larvae

(refer to diagram on page 332) Mosquito bites human and ingests microfilariae. Microfilariae bore through mosquito stomach and thoracic muscles; in about 10 days they develop into larvae. Mosquito bites human; larvae emerge from mouthparts onto skin and enter body through bite wound. Larvae migrate to lymphatic vessels and lymph nodes. After growing to maturity in about 6 months, the larvae block lymphatic drainage, causing elephantiasis. Adult worms mate. Microfilariae are produced through and migrate to peripheral circulation remaining in tiny capillaries of lungs during the day.

Louis Pasteur's Silkworm Experiment

-Transfer microorganisms from diseased silkworms to normal silkworms and normal ones become diseased -Prevent normal silkworms from contact w/ disease and they will stay normal

Bacteriophages are double-stranded virus that infect and replicate only in bacteria. They should be grouped into Baltimore Group ____ .

1

Adenoviruses are Baltimore group ____ viruses. They may spread and cause respiratory tract infections through ____ .

1 ..... respiratory droplets

Robert Koch's Contributions

1) Germ Theory 2) Identify causative microorganismi for... Anthrax (Bacillus anthracis), Cholera (Vibrio cholerae), & Tuberculosis (Mycobacterium tuberculosis) 3) Pure Bacterial Culture - One microbe on petri dish 4) Koch's Postulates - Regarded as the gold standard of pathogen identification

Koch's Postulates

1) The suspected pathogen must be present in all cases of disease, but absent in the healthy. 2) The suspected pathogen must be grown as a pure culture. 3) Pure culture of suspected pathogen can cause the same disease in a healthy individual. 4) The same pathogen can be isolated from the diseased individual, & grown as the same pure culture.

Mechanisms of Resistance

1. Alteration of Targets 2. Alteration of Membrane Permeability 3. Development of Enzymes 4. Alteration of an Enzyme 5. Alteration of a metabolic pathway

disinfectant selection

1. Be fast acting even in the presence of organic substances, such as those in body fluids. 2. Be effective against all types of infectious agents without destroying tissues or acting as a poison if ingested. 3. Easily penetrate material to be disinfected without damaging or discoloring the material. 4. Be easy to prepare and stable even when exposed to light, heat, or other environmental factors. 5. Be inexpensive and easy to obtain and use. 6. Not have an unpleasant odor.

Modes of Action (5)

1. Inhibition of call wall synthesis 2. Disruption of cell membrane functions 3. Inhibition of protein synthesis 4. Inhibition of nucleic acid synthesis 5. Actions as metabolites

Steps in pathogenesis

1. Maintain a reservoir (other humans, animals, environment) 2. Initial transport to host and entry (direct or indirect) 3. Adhere to, colonize, or invade host cells or tissues 4. Evade host defense mechanisms 5. Multiply in the host (or complete life cycle) 6. Damage the host 7. Leave host and return to reservoir or new host

Types of genetic changes

1. Natural Selection 2. Chromosomal Mutation 3. Extrachromosomal Resistance 4. R Plasmids or R factors

General Properties of Antimicrobial Agents (5)

1. Selective Toxicity 2. The Spectrum of Activity 3. Modes of Action 4. Side Effects 5. Resistance of Microorganisms

2 Types of drugs

1. Synthetic 2. Semi-synthetic

Koch's postulates

1. The specific causative agent must be observed in every case of a disease 2. The agent must be isolated from a diseased host and must be grown in pure culture 3. When the agent from the pure culture is inoculated into a healthy but susceptible experimental host, the agent must cause the same disease 4. The agent must be reisolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent.

Kinds of Side Effects

1. Toxicity 2. Allergy 3. Disruption of normal microbiota (normally present)

Log Phase

1.Growth occurs at an exponential or logarithmic rate. 2.Growth in this phase appears on a graph as a straight diagonal line, which represents the size of the bacterial population 3.The organisms divide at their most rapid rate-a regular, genetically determined interval called the generation time.

Decline Phase

1.Many cells lose their ability to divide and die 2.The number of live cells decreases at a logarithmic rate as indicated by the straight, downward sloping diagonal line 3.Many cells undergo involution-they assume a variety of unusual shapes which makes them difficult to identify.

Robert Hooke

1st Compound Microscope Observed thin slices of cork Described "Cell"

Edward Jenner

1st to Vaccinate

Parvoviruses are Baltimore group ____ viruses. These viruses depend on ____ to make mRNA.

2 ..... DNA-dependent RNA polymerase

Commensalism

2 species live together in a relationship where one benefits and the other neither benefits or is harmed

Reoviruses are Baltimore group ____ viruses. These viruses depend on ____ to replicate their genome.

3 ..... RNA-dependent RNA polymerase

How much of an adult's body weight is microflora?

3%

Coronaviridae is classified in Baltimore group ____ . Main diseases caused by coronaviruses infection include upper respiratory tract infections, and common cold, so they may spread by ____ .

4 ..... respiratory droplets

Mumps virus is classified to Baltimore group ____ , the ____ family.

5 ..... paramyxoviridae

The genome of hepatitis B virus is of dsDNA type. This virus is classified to Baltimore group ..... . HBV viral replication involves ____ intermediate, which is reverse transcribed into DNA.

7 ..... pre-genomic RNA

A typical bacterial cell has a salt concentration of about 1%. If the cell is placed in a solution containing 10% salt, the net flow of water will be _____. a) out of the cell b) into the cell c) equally in and out of the cell d) none of the above since water doesn't cross bacterial cell membranes

A

Amino acids in a protein are joined together by _____. a) peptide bonds b) hydrogen bonds c) phosphodiester bonds d) tertiary bonds

A

Bacterial ribosomes: a) have a sedimentation rate of 70S b) are made up of 30S and 40S subunits c) have a sedimentation rate of 80S d) are made up of 50S and 30S subunits

A

Chemically stable atoms are inert or less likely to form chemical bonds. A chemically stable element: a) has l full outer electron shell b) has the same number of protons as electrons c) has an atomic number is equal to the atomic mass d) forms hydrogen bonds

A

Disaccharides, such as sucrose and lactose, are formed from: a) two monosaccharides connected by a glycosidic bond. b) chains of two amino acids. c) long chain of carbon atoms and a carboxyl group at one end of chain. d) three fatty acids combined with glycerol.

A

Food consists of molecules with lots of energy stored in their chemical bonds. What is true about how microorganisms use nutrients? a) When microorganisms break the chemical bonds in nutrients, they release energy. b) It takes microorganisms more energy to break the bonds in nutrients than are released. c) All energy that microorganisms receive from nutrients comes from anabolism. d) Microorganisms break down hydrogen bonds to release electrons as energy.

A

In order to become an ion, an atom of chlorine must _____. a) gain an electron b) form a covalent bond c) lose an electron d) form a hydrogen bond

A

Osmosis most directly involves: a) water moving down a concentration gradient b) organic molecules crossing a membrane c) energy being expended to import large molecules into the cell d) sugars and salts moving down their concentration gradient

A

Phospholipids: a) have a charged phosphate group that can mix with water and insoluble fatty acids. b) can serve as hormones. c) always remain liquid at room temperature. d) form straight chains in water.

A

Removal of the cell wall of a Gram positive bacteria results in the formation of a _____. a) protoplast b) spheroplast c) periplast d) polyplast

A

Solutions made up of molecules that are not chemically bonded and are not limited to specific proportions are called: a) mixtures b) elements c) chemical compounds d) polar compounds

A

Some bacteria can transfer DNA to another cell using: a) conjugation pili b) fimbriae c) axial filaments d) lophotrichous flagella

A

The specific sequence of amino acids in a protein is known as its: a) primary structure b) secondary structure c) tertiary structure d) quaternary structure

A

What is true about oxidation? a) The more oxidized a molecule, the less energy it contains. b) Oxidation is the removal of oxygen or the addition of hydrogen or electrons to a substance. c) Gasoline represents the extreme of energy-rich oxidized compounds. d) Oxidation reactions only occur in polar compounds.

A

When glucose is dissolved in water, the water is the ________ and the glucose is the ________. a) solvent, solute b) solvent, solution c) solute, solvent d) solute, solution

A

When sodium hydroxide, a strong base, is added to water, the pH of the solution _____. a) goes up. b) remains the same. c) goes down. d) cannot be determined.

A

Which is the correct ordering of cell wall components starting from outside the cell and going inward? a) In gram positive bacteria: peptidoglycan, cell membrane b) In gram negative bacteria: peptidoglycan, lipopolysaccharide, periplasmic space, outer membrane, cell membrane c) In acid fast bacteria: peptidoglycan, lipid layer, cell membrane d) In gram negative bacteria: peptidoglycan, periplasmic space, lipid membrane

A

Which of the following is not a colloid? a) salt water b) gelatin desserts c) agar plates used to grow microorganisms d) fluid in cells

A

Which of the following is true about bacteria? a) All bacteria cells are smaller than 100 micrometers in diameter. b) The cell wall controls the movement of small molecules into and out of the cell. c) Gram negative bacteria become protoplasts when their cell wall is digested away. d) Bacterial endospores are reproductive structures.

A

Prokaryotic cells divide by _____. a) mitosis b) binary fission c) meiosis d) mitosis asexually and meiosis sexually

B

Which of the following statements about cell walls is false? a) All bacterial cell walls contain teichoic acids. b) Plants and fungi have cell walls. c) Bacteria which have lost their cell wall are known as L-forms. d) Algal protists have cell walls.

A

Which of the following statements about outer membranes is true? a) It contains an endotoxin (lipopolysaccharide) which is responsible for fever and potentially serious complications in human infections. b) It prevents the cell from lysing when fluids flow into the cell. c) Treatment with antibiotics which kill the bacteria will reduce the concentration of endotoxin. d) It is a space that is very active in cell metabolism

A

Which of the following statements about the prokaryotic cells surface-to-volume ratio is false? a) Because of their small size, bacteria have a small surface-to-volume ratio b) Eukaryotes have surface-to-volume ratio that is only 1/10 that of prokaryotes c) The prokaryotes surface-to-volume ratio means that nutrients can easily and quickly reach all parts of the cell as no internal part of the cell is very far from the surface. d) A bacteria with a surface area of about 12 microns squared and a volume of 4 cubic microns has a surface-to-volume ratio of 3:1

A

Which of the following statements is false? a) All bacteria are capable of forming capsules. b) The chemical composition of each capsule is unique to a particular strain of bacteria. c) Slime layers are usually thinner than capsules. d) A slime layer protects bacteria against drying and helps trap nutrients near a cell.

A

Which one of the following pairs is matched correctly? a) carbon-organic compounds b) glucose- hydrogen bonds c) ions-covalent bonds d) phosphate-enzyme

A

Which statement is true for radioisotopes? a) Radioisotopes have unstable nuclei that emit subatomic particles and radiation. b) All radioisotopes have gained electrons. c) Radioisotopes are useful to guard against radioactive elements. d) Radioisotopes contain particles too large to form true solutions.

A

[Insert Fig. 4.3 - Remove all leaders lines and text] 58) This type of cell is a _____. a) prokaryote. b) eukaryote. c) Both A and B are correct d) Neither A nor B are correct

A

_____ occurs when bacteria differ widely in form. a) Pleomorphism b) Polymorphism c) Anamorphism d) Telomorphism

A

Binary Fission

A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size

trophozoite

A growing stage in the life cycle of some sporozoan parasites, when they are absorbing nutrients from the host.

septa

A hypha consists of one or more cells surrounded by a tubular cell wall. In most fungi, hyphae are divided into cells by internal cross-walls called "septa" (singular septum). Septa are usually perforated by pores large enough for ribosomes, mitochondria and sometimes nuclei to flow between cells.

mycelium

A loosely organized mass of threadlike structures called hyphae. Mycelial cells release enzymes that digest the substratum (the surface on which the fungus grows) and absorb small nutrient molecules.

Turbidity

A measure of how clear water is Useful in monitoring the rate of growth without disturbing the culture. Can be produced by a high concentration of dead cells in a culture

Pour Plate Method

A method of inoculating a solid nutrient medium by mixing bacteria in the melted medium and pouring the medium into a Petri dish to solidify

sporozoite

A motile sporelike stage in the life cycle of some parasitic sporozoans (e.g., the malaria organism) that is typically the infective agent introduced into a host. A spore formed after fertilization; any one of the sickle-shaped nucleated germs formed by division of the protoplasm of a spore of a sporozoan organism.

hyperparasitism

A parasite itself having a parasite. An organism that is parasitic on another parasite. hyperparasite. A condition in which a secondary parasite develops within a previously existing parasite.

Plasmolysis

A phenomenon in walled cells in which the cytoplasm shrivels and the plasma membrane pulls away from the cell wall; occurs when the cell loses water to a hypertonic environment.

ascospore

A sexually produced fungal spore formed within an ascus of ascomycetes. Have a haploid number of chromosomes and are formed by meiosis of the diploid zygote that results when the nuclei of sexually compatible hyphae fuse together.

diatom

A single-celled alga that has a cell wall of silica. Many kinds are planktonic, and extensive fossil deposits have been found. Lack flagella and are especially numerous group that are important as producers in freshwater and marine environments.

dinoflagellate

A single-celled organism with two flagella, occurring in large numbers in marine plankton and also found in fresh water. Some produce toxins that can accumulate in shellfish, resulting in poisoning when eaten. Plantlike protists that usually have 2 flagella, one extending behind the organisms like a tail and the other lying in a transverse groove. May have a cell wall, some have theca which is a tightly fixed, secreted layer that typically contains cellulose. Some exhibit bioluminescence.

merozoite

A small ameboid sporozoan trophozoite (as of a malaria parasite) produced by schizogony that is capable of initiating a new sexual or asexual cycle of development.

Most Probable Number

A statistical method of measuring bacterial growth used when samples contain too few organisms to give reliable measures by the plate count method

zygospore

A thick walled, resistant structure that also produces spores.

biological vector

A vector that is essential in the life cycle of a pathogenic organism. A vector in which the parasite goes through part of its life cycle.

mechanical vector

A vector that simply conveys pathogens to a susceptible individual and is not essential to the development of the organism. A vector in which the parasite does not go through any part of its life cycle during transit.

superficial disease

Affect only keratinized tissue in the skin, hair, and nails.

subcutaneous disease

Affect skin layers beneath keratinized tissue and can spread to lymph vessels.

vector

Agents of transmission. Is an organism that does not cause disease itself but which spreads infection by conveying pathogens from one host to another.

Microorganisms Include...

All Prokaryotes (W/O Nucleus) All Eukaryotes (W/ Nucleus) Small-Sized Eukaryotes

Normal Microflora

All the microorganisms that exist on the surface and inside a healthy normal person -An adult has 30 trillion human cells -An adult carries 100 trillion microorganisms

fungi imperfecti

Also known as deuteromycota. No sexual stage has been observed in their life cycle.

definitive host

An organism that supports the adult or sexually reproductive form of a parasite. They harbor parasites while it produces sexually.

intermediate host

An organism that supports the immature or nonreproductive forms of a parasite. They harbor the parasite during some other developmental stage.

Proteins are chains of ______ that sometimes function as________. a) disaccharides; cell wall b) amino acids; enzymes c) lipids; energy compounds d) glycogen ; enzymes

B

animal-like protist

Animal-like protists or protozoan are primarily identified by method of movement such as:  Pseudopods or "false feet" - amoeba and organisms belonging to Sarcondine Phylum have no true shape, moving via projections of cytoplasm Cilia - paramecium and plankton from Ciliate Phylum use tiny hairs that line the outside of the cell Flagella - from the Phylum Mastigophorans; Euglenoids whip a sole flagellum, Dinoflagettes use two flagella Animal-like protozoan are also heterotrophic and contain organelles such as a cell membrane and food vacuole.

euglenoid

Any member of the protist phylum Euglenophyta, comprising unicellular organisms, either green and photosynthetic or colorless and nonphotosynthetic, characterized by one or two anterior flagella and, in photosynthetic forms, an eyespot at the base of the flagella: in some classification schemes, an order of the animal. Usually have a single flagellum and a pigmented eyespot called stigma. The stigma may orient flagellar movement so that organisms moves toward light. It usually has an elongated, cigar-shaped, flexible body. Instead of a cell wall it has a pellicle or outer membranous cover and usually reproduce by binary fission.

fungi

Any of a diverse group of eukaryotic single-celled or multinucleate organisms that live by decomposing and absorbing the organic material in which they grow, comprising the mushrooms, molds, mildews, smuts, rusts, and yeasts, and classified in the kingdom Fungi or, in some classification systems, in the division Fungi. Produce sexually and asexually. Fungi usually go through haploid, dikaryotic, and diploid phases in their life cycle. Fungi are important decomposers. Parasitic fungi can be destructive when they invade other organisms. these fungi have 3 requirements for invasions: 1. Proximity to the host 2. The ability to penetrate the host 3. The ability to digest and absorb nutrients from host cells. (under construction)

sac fungi

Are a diverse group containing over 30,000 species, including yeasts. Have chitin in their cell walls and produce no flagellated spores. The hyphae have septa with a central pore. Properly known as Ascomycota. Unlike other fungi they produce a saclike ascus during sexual reproduction. In species that reproduce both sexually and asexually, the asexual phase forms spores called conidia at the ends of modified hyphae. In the sexual phase, the mycelium that produces conidia also forms the gamete producing structures, antheridia (male) and ascogonia (female). After cytoplasmic fusion of those structures occurs, dikaryotic hyphal cells develop and interweave into an ascocarp, where saclike asci grow. In each ascus, the dikaryotic nuclei fuse to form zygote, and the zygote nucleus divides into eight nuclei. From them, eight ascopores form and are forcefully released.

reservoir host

Are infected organisms that make parasites available for transmission to other hosts.

apicomplexan

Are parasitic and immobile. Enzymes present in groups (complexes) of organelles at the tips (apices) of their cells digest their way into hosts cells, giving the group the name. Have a complex life cycle. The apicomplexa have complex life cycles that are characterized by three distinct processes: sporogony, merogony and gametogony (Figure). Although most apicomplexa exhibit this overall general life cycle the details can vary between species. Sporogony occurs immediately after a sexual phase and consists of an asexual reproduction that culminates in the production of sporozoites. Sporozoites are an invasive form that will invade cells and develop into forms that undergo another asexual replication known as merogony. Merogony and the resulting merozoites are known by many different names depending of the species. In contrast to sporogony, in which there is generally only one round of replication, quite often there are multiple rounds of merogony. In other words, the merozoites, which are also invasive forms, can reinvade cells and initiate another round of merogony. Sometimes these multiple rounds of merogony will involve a switch in the host organism or a switch in the type of cell invaded by the parasite resulting in distinct stages of merogony. As an alternative to asexual replication merozoites can develop into gametes through a process variously called gametogony, gamogony or gametogenesis. As in other types of sexual reproduction, the gametes fuse to form a zygote which will undergo sporogony. Apicomplexa is a phylum comprised of protozoans characterized by having a special organelle called an apical complex, and most of them are single-celled, parasitic, and spore-forming. They are intracellular parasites. Their life cycle is comprised of stages where each has a particular cellular variety. Nevertheless, not all members have all the various life stages. An example is the Plasmodium species causing malaria in humans. Plasmodium species use two hosts (human and Anopheles mosquito) to complete its complex life cycle. In human host, the sporozoites injected by the mosquito during a blood meal are circulated by the bloodstream. When they reach the liver cells of the human host they transform into a trophozoite, losing its apical complex and surface coat. They particularly invade the vacuole of the hepatocyte where they will go through schizogonic development. Their nucleus will undergo multiple divisions while their cell size increases. They develop and differentiate into merozoites. These merozoites are released from the hepatocytes and enter the bloodstream. They, then, invade the red blood cells to initiate the erythrocytic stage. Merozoites at this point have their apical coplex, pellicle and surface coat for use in invading red blood cell. In the erythrocytic stage, the merozoites may give rise to either trophozoites or gametocytes. (under construction)

How virulence of a pathogen can be decreased based on its host

Attenuation: weakening of the disease-producing ability of the pathogen Can be achieved by: repeated subculturing on lab media or by transposal of virulence (pathogen is passed from its normal host to a new host species and then passed through many individuals of the new host species). It adapts so completely to the new host that it is no longer virulent to the original host. → virulence transposed to another organism.

Inhibition of cell wall synthesis EXAMPLES

penicillin bacitracin cephalosporin vancomycin

Atoms are most likely to form ions when they have: a) an even number of electrons in their outer shells b) a nearly empty outer shell c) an odd number of electrons in their outer shells d) four electrons in their outer shells

B

Atoms take part in bond formation to: a) form polypeptides b) attain a stable electron configuration c) increase their charge density d) increase their energy

B

Bacteria move by means of: a) cilia b) flagella c) fimbriae d) pili

B

Bacteria with flagella all over their surface are said to be: a) monotrichous b) peritrichous c) amphitrichous d) lophotrichous

B

Charged atomswith electrostatic attraction are generally held together by _____. a) covalent bonds b) ionic bonds c) hydrogen bonds d) municipal bonds

B

During diffusion, molecules _____. a) move from hotter areas to cooler areas b) move from areas of higher concentration to areas of lower concentration c) move from areas of lower concentration to areas of higher concentration d) expend energy to more around

B

Endocytosis: a) releases material in the form of phagosomes. b) is the process of taking materials into the cell. c) directs material to the endoplasmic reticulum. d) uses simple diffusion move material across the plasma membrane.

B

Endospores are typically found in the genus: a) Streptococcus b) Clostridium c) Mycobacterium d) Staphylococci

B

Endospores are usually induced to form when: a) temperatures rise b) certain nutrient are depleted c) radiation is detected d) water is lost from the cell

B

Extrachromosomal DNA in prokaryotic cells can be found in the form of _____. a) chromosomes b) plasmids c) mitochondria d) chloroplasts

B

Fatty acids that are _________ have ___________ . a) saturated; lost their secondary structure b) unsaturated, a double bond between two carbons that have lost hydrogen atoms c) saturated, one or more double bonds d) denatured, all the hydrogen it can.

B

In DNA, the nucleotide cytosine always base pairs to: a) adenine b) guanine c) thymine d) uracil

B

Ketones, alcohols, aldehydes and organic acids are four of the organic compounds found in all living cells. What do these four classes of organic compounds share? a) They contain the same atoms but differ in structure. b) They are chains of carbon atoms with functional groups that contain oxygen. c) They are all fully oxidized. d) They can only be synthesized inside a cell.

B

Peptidoglycan makes up more than 50% of a ________ cell wall. a) Gram negative b) Gram positive c) Gram variable d) acid-fast

B

Incubation period

the time between infection and the appearance of signs and symptoms

The Fluid-mosaic model describes the structure of _____. a) cell walls b) cell membranes d) capsules d) endosymbiotic relationships

B

The _____ portion of the cell membrane functions as a barrier while the ______ portion provides specific functions, including pumps, receptors, adhesion, etc. a) carbohydrate; nucleic acid b) lipid; protein c) lipid; carbohydrate d) nucleic acid; lipid

B

The charged, phosphate end of a membrane phospholipid is: a) water-fearing b) hydrophilic c) hydrophobic d) none of the above

B

The flagellar arrangement represented in this image is_____. a) monotrichous b) peritrichous c) amphitrichous d) lophotrichous

B

The shape of a bacterial cell is determined (and maintained) by the _____. a) cell membrane b) cell wall c) capsule d) slime layer

B

Two or more atoms combine to form a/an: a) cation. b) molecule. c) protein. d) ion.

B

What is the function of gas-filled vacuoles in aquatic photosynthetic bacteria? a) transducers to detect chemicals and signal the cells to respond b) regulate the depth at which they float by changing amount of gas in vacuoles c) change the handedness of the helix in which the bacteria is moving d) allows the bacteria to respond to magnetic fields

B

When pairs of electrons are shared between two atoms, the result is a/an _______ bond. a) ionic b) covalent c) hydrogen d) carbonic

B

Which is a false statement about chemical reactions? a) Catabolic reactions are exergonic and release energy. b) Polymerization and the building up of large molecules is a catabolic reaction. c) Anabolic reactions require energy. d) Energy is stored in the form of chemical bonds.

B

Which of the following cellular structures are found only in prokaryotic cells? a) endoplasmic reticulum b) pili c) nucleolus d) lysosomes

B

Which of the following statements about motility is false? a) Chemotaxis is the movement of bacteria toward or away from a chemical. b) Pseudopodia are associated with fungi. c) Bacteria use helical flagellar movements to orient towards external signals. d) Pseudopodia are temporary projections of cytoplasm.

B

Which of the following statements about solutions is false? a) The solute is the substance dissolved in a solvent. b) Left alone on a counter, a solution will separate out. c) Solutes can consist of atoms, ions or molecules. d) In cells, water is typically a solvent.

B

Which statement about acids and bases is false? a) A hydrogen ion (H+) is a proton. b) Acids are proton acceptors. c) Bases are proton acceptors d) A hydroxyl ion donor is also a proton acceptor

B

thallus

Body of fungus.

control of microbial growth

Both the growth and death of microorganisms occur at log rates. When heat is applied to a material, the death rate of the organisms in or on it remains logarithmic but is greatly accelerated. Heat acts as antimicrobial agent. 1. A definite proportion of the organisms die in a given time interval. The total number of organisms present when disinfection is begun affects the length of time required to eliminate them. 2. The fewer organisms present, the shorter the time needed to achieve sterility. The effectiveness of a chemical antimicrobial agent is affected by time, temperature, pH, and concentration. 3. Microorganisms differ in their susceptibility to antimicrobial agents.

Sulfonamides, Chepalosporins

Broad: gram-negative and gram-postitve

Penicillins

Broad: gram-negative, gram-positive, and chlamydias

Tetracyclines

Broad: gram-negative, gram-positive, chlamydias, rickettsias

Hydrogen bonds are generally: a) stronger than covalent bonds b) stronger than ionic bonds but weaker than covalent bonds c) present in large numbers d) found in non-polar compounds

C

Attenuation

the weakening of a disease-producing ability of the pathogen

Carbohydrates: a) are hydrophobic. b) have a four ring structure. c) are used primarily for energy and cellular structures. d) have primary, secondary, tertiary and quaternary structure.

C

Chemical bonds usually form between atoms through the interaction of: a) protons b) neutrons c) electrons d) isotopes

C

Chemical reactions occur: a) between elements that have magnetic repulsion. b) rarely as very few elements have electrons in their outer shell. c) during metabolism as they are necessary for making the substance of cells. d) only in eukaryotes as they require a nucleus.

C

Coccus-shaped cells which divide along two planes will produce cells arranged into _____. a) diplococci b) streptococci c) tetrads d) staphylococci

C

In bacteria, the cell membrane functions in the all of the following ways except: a) regulate movement of materials into and out of the cell b) synthesizes cell wall components c) serve as the site for protein synthesis d) assists with DNA replication

C

In salt, a sodium atom loses an electron to a chlorine atom. What is true about the chloride ion found in salt? a) It has one less electron than proton. b) It is less chemically stable than a chlorine atom. c) It is an anion. d) It is in a covalent bond.

C

Lysozyme, found in human tears, controls the growth of bacteria by _____. a) fusing with vacuoles b) containing multiple kinds of digestive enzymes c) digesting peptidoglycan d) preventing peptidoglycan synthesis

C

Mitochondria: a) are responsible for converting sunlight to chemical energy b) are present only in photosynthetic organisms c) have a double membrane d) are responsible for protein synthesis

C

Organic molecules with the same molecular formula but different structures are: a) elements b) isotopes c) isomers d) anions

C

Polysaccharides: a) include ribose, fructose and glucose. b) include cholesterol and vitamin D. c) are monosaccharides joined by glycosidic bonds. d) are found only in eukaryotic cells.

C

The atomic nucleus consists of: a) cations and anions b) protons, electrons and neutrons c) protons and neutrons d) solutes and colloids

C

The cytoskeleton consists of _____. a) microfilaments and sterols b) microtubules and proteins c) microfilaments and microtubules d) sterols and proteins

C

The most important structural component of bacterial cell walls is _____. a) teichoic acid b) lipotechoic acid c) peptidoglycan d) glutamic acid

C

The outer (cell) membrane component of the cell wall _____. a) is found only in Gram positive bacteria b) is made primarily of peptidoglycan c) contains lipopolysaccharrides d) is primarily a reproductive structure

C

Ellie Mechnikoff

Cell-Mediated Immunity - Certain cells in the body can ingest microbes "Macrophages"

The pH scale is used to specify the acidity or alkalinity of a solution. Which of the following statements is true? a) Stomach acid has a pH around 10. b) Neutral solutions, like water, have a pH of 10. c) A solution with a pH of 12 has 10 times the number of protons as a solution with a pH of 11. d) A strong base will have a pH less than 10.

C

The rough endoplasmic reticulum appears rough because of _____. a) sterols in its membrane b) fats and sugars on its surface c) multiple ribosomes on its surface d) proteins in the lumen of the ER

C

This structure can be Gram positive or Gram negative. a) A b) B c) C d) D

C

Which bacterial genus normally lacks a cell wall? a) Mycobacterium b) Streptococcus c) Mycoplasma d) Bacillus

C

Which of the following is a three carbon sugar alcohol? a) a b) b c) c d) d

C

Which of the following is not a common bacterial shape? a) Spirochete b) Coccus c) Disc d) Bacillus

C

Which of the following statements about the endosymbiotic hypothesis is false? a) Eukaryotic cells have both 70S and 80S ribosomes. b) Mitochondria have their own DNA. c) When removed from cells, mitochondria continue to grow and divide. d) Mitochondria are about the same size as prokaryotic cells.

C

Which of these statements about eukaryotic cell division is false? a) the nuclei of eukaryotic cells divide via the process of mitosis b) haploids are cells that receive only one chromosome from each pair of chromosomes c) a single round of mitosis results in the production of four haploid cells d) during mitosis the nuclear envelope breaks apart and the spindle apparatus forms

C

While division in one plane produces cells in pairs, what does random division produce? a) Sarcinae b) Eight cells arranged in a cube c) Grapelike clusters (staphylo-) d) Four cells arranged in a cube

C

Small-Sized Eukaryotes

Certain Worms -Parasitic Worms- Helmiths Certain Arthropods (Parasitic and/or pathogen carriers) -Insects - Jouse, Flee -Arachnids - Ticks Certain Fungi Certain Multicellular Algae

Paul Ehrlich

Chemotherapy Found chemical compounds that can destroy bacteria, but not harm the body's own cells Compound 606 - Treats syphilis by killing off Treponema pallidum Humoral Immunity - Body makes specific defense molecules in blood called "antibodies"

refrigeration, freezing, and drying

Cold temperatures retards the growth of microorganisms by slowing the rate of enzyme-controlled reactions but does not kill many microbes. Refrigeration is used to prevent food spoilage. Freezing and drying are used to persevere both foods and microorganisms but does not achieve sterilization. Refrigeration slows the rate of enzyme controlled reactions Freezing greatly slows the rate of most enzyme controlled reactions Drying inhibits enzymes Freeze drying dehydrates inhibits enzymes

What is the difference between communicable and noncommunicable diseases

Communicable: diseases that can be spread from one host to another Noncommunicable: not spread from one host to another. Cannot "catch a noncommunicable disease from another person.

ultraviolet light

Consists of light of wavelengths between 40 and 390 nm, effective at killing microorganisms by damaging DNA and proteins. It is absorbed by purines and pyrimidines bases of nucleic acids and such absorption can permanently destroy these important molecules.

arthropod

Constitute the largest group of living organisms. Are characterized by jointed chitinous exoskeletons, segmented bodies and jointed appendages associated with some or all of the segments. The exoskeleton both protects the organisms and provides sites for the attachment of muscles. Have a small brain and an extensive network of nerves.

What is the relationship among the terms contamination, infection, and disease?

Contamination: foreign microbes are present. Inanimate objects and the surfaces of the skin and mucous membranes can be contaminated with a wide variety of microbes. Infection: the multiplication of any parasitic organism within or on the host's body. If an infection disrupts the normal functioning of the host, it becomes a disease Disease: a disturbance in the state of health wherein the body cannot carry out all its normal functions.

Rabies Vaccination

Contribution of Louis Pasteur 1) Dry & Grind up spinal cords of rabbits with rabies 2) Inject powder into humans to prevent rabies infection

Pasteurization

Contribution of Louis Pasteur 1) Heating at 162F for 15 seconds 2) Inactivates and kills most common pathogenic bacteria 3) Standard public safety process in food industry

What do Microflora do for an adult's health?

Crowd and suppress harmful microbes Synthesize Vitamin K & B12

A charged molecule which moves down its concentration gradient and across a pore in a cell membrane without energy being expended by the cell is experiencing _____. a) simple diffusion b) osmosis c) active transport d) facilitated diffusion

D

A nucleic acid has a "backbone" consisting of: a) nitrogenous bases b) sugars c) phosphates d) b and c are correct

D

A small comma shaped bacteria is described as being a ________. a) spirochete b) bacillus c) spirillum d) vibrio

D

An ion is all of the following except: a) a charged atom b) an atom that has lost or gained one or more electrons c) either a cation or an anion d) an atom with the same number of protons as electrons

D

Anabolic reactions tend to: a) use energy and break chemical bonds. b) produce energy, and break chemical bonds. c) produce energy and new chemical bonds. d) use energy and produce new chemical bonds.

D

Attachment pili do all of the following except, a) help bacteria adhere to surfaces b) allow bacteria to form a pellicle at the air-water interface of a broth culture c) clump blood cells in a process called hemagglutination d) prevent the pathogenicity of certain bacteria

D

Bacilli produce fewer arrangements than cocci because _____. a) cocci are smaller than bacilli b) bacilli only reproduce asexually c) bacilli divide along several different planes while cocci divide along a single plane d) cocci divide along several different planes while bacilli divide along a single plane

D

Carbohydrates do not include which of the following? a) Glucose b) Starch c) Cellulose d) Sterols

D

Chemical bonds found in living organisms do not normally include: a) ionic bonds b) hydrogen bonds c) covalent bonds d) magnetic bonds

D

Chemical reactions that require energy are best termed _____. a) catabolic b) anabolic c) exergonic d) endergonic

D

Electrons have a _______ charge and are found in the _________. a) positive; inner electron shell b) positive; outer electron shell c) negative; nucleus d) negative; outer electron shell

D

Eukaryotic cells add rigidity to their plasma membrane by including what component in the membrane? a) Protein b) Lipids c) Sugars d) Sterols

D

Genetic information in bacteria is: a) found in the nucleus b) found only in RNA c) found in DNA condensed by histones d) sometimes found in the form of plasmids

D

Glucose: a) is abundant in milk and fruit b) is a rare monosaccharide c) is never produced within cells d) none of the above

D

Inclusions found in bacteria generally would not include: a) granules b) volutin c) metachromatic granules d) ribosomes

D

Molecules that contain mixtures of different elements are called _____. a) isotopes b) atoms c) ions d) compounds

D

Mycolic acid would be found primarily in the cell wall of: a) Gram positive bacteria b) Gram negative bacteria c) Gram variable bacteria d) acid-fast bacteria

D

Penicillin controls the growth of bacteria by _____. a) destroying cell membranes b) preventing protein synthesis c) removing cell walls d) preventing peptidoglycan synthesis

D

The double helix is a structure associated with: a) disaccharides b) a compound with hydrogen bonds c) lipids d) DNA

D

The periplasmic space is found _____. a) only in Gram positive organisms b) between the nuclear area and the cell membrane c) primarily in acid fast bacteria d) between the innercell membrane and outer cell wall membrane

D

The smallest particle of matter that can take part in chemical reactions is: a) glucose b) compound c) neutron d) atom

D

The three fundamental particles of the atom are _____. a) elements, molecules, and compounds b) ions, cations, and anions. c) proteins, lipids, and sugars d) protons, neutrons, and electrons.

D

The total number of protons in an atom is equal to its _____. a) atomic weight b) molecular weight c) chemical weight d) atomic number

D

Water plays an important role in the chemical reactions in cells, including: a) denaturing proteins b) stabilizing the primary structure of a protein c) forming covalent bonds with proteins d) breaking down large proteins into amino acids in hydrolysis reactions

D

What is true about atomic weight? a) It is the sum of the number of electrons and protons in an atom. b) The higher the atomic weight the more likely an atom will form a chemical bond. c) It is always a whole number. d) Atoms of a particular element that have different atomic weights are called isotopes.

D

When proteins are made up of several polypeptide chains, the arrangement of these chains is referred to as the: a) primary structure b) secondary structure c) tertiary structure d) quaternary structure

D

When the fluid within a cell has a higher concentration of dissolved substances than the fluid surrounding the cell, we say the fluid surrounding the cell is _____. a) hypertonic b) isotonic c) superhypertonic d) hypotonic

D

Which is a false statement about water? a) Water molecules are polar. b) Water has a high specific heat because of the extensive covalent bonding between molecules. c) Hydrogen atoms in water form dipoles with a partial positive charge. d) Water's polarity allows for many ionic compounds to be dissolved in it.

D

Which of the following cellular structures can be found in both prokaryotic and eukaryotic cells? a) Golgi apparatus b) lysosomes c) peroxisomes d) ribosomes

D

Which of the following groups of organisms is not prokaryotic? a) Archaea b) Bacteria c) Eubacteria d) Eukarya

D

Which of the following has the fewest hydrogen ions? a) Stomach hydrochloric acid b) Urine c) Ocean water d) Household ammonia

D

Which of the following has the fewest hydroxyl ions? a) Oven cleaner b) Household bleach c) Saliva d) Vinegar

D

alkylating agents

Disrupt the structures of both proteins and nucleic acids. Because they can disrupt nucleic acids they are believed to cause cancer.

Which of the following is not found in bacterial cells? a) A cell membrane, usually surrounded by a cell wall b) An internal cytoplasm with ribosomes, a nuclear region and in some cases granules c) A variety of external structures, such as capsules, flagella and pili d) Respiratory enzymes contained in an internal structure surrounded by membranes

D

Which of the following is responsible for converting sunlight into chemical energy? a) Chromatophores b) Chloroplasts c) Endoplasmic reticulum d) Two of the above

D

Which of the following pH values would indicate the weakest acid? a) 2 b) 3 c) 4 d) 5

D

Which of the following pairs is mismatched? a) Protein-amino acids b) Nucleic acids-nucleotides c) Polysaccharides - simple sugars d) Fats-aldehyde

D

Which of the following structures is not normally part of a bacterial flagellum? a) Hook b) Filament c) Basal body d) Anchor

D

dry heat

Damages by oxidizing molecules. Penetrates substances more slowly and it usually used to sterilize metal objects and glassware. Example: Open Flame

moist heat

Destroys microorganisms mainly by denaturing proteins, the presence of water molecules helps disrupt the hydrogen bonds and other weak interactions that hold protein shapes. Example: Autoclave. In this procedure it is the increased temperature, and not the increased pressure that kills microorganisms. Very useful when articles are placed in the autoclave so that the steam can easily penetrate them, also air should be evacuated.

Martinus Beijerinck

Determined the Chamberland Filter cannot filter out infectious pathogens

Ernst Ruska & Max Knoll

Developed the electron microscope

Charles Chamberland

Developed ultra filtration to filter out bacteria

Serial Dilution

Dilution of a substance several times by the same amount each time

Alexander Fleming

Discovered the first antibiotics - Penicillin

phenols

Disrupt cell membranes, denature proteins, and inactivate enzymes. They are used to disinfect surfaces and to destroy discarded cultures because their action is not impaired by organic materials. Disrupt membranes, denature proteins, and inactivate enzymes; not impaired by organic matter.

oxidizing agents

Disrupt disulfide bonds in proteins and thus disrupt the structure of membranes and proteins. Hydrogen peroxide is used to clean punter wounds for example. It breaks down into oxygen and water, the oxygen kills obligate anaerobes present in the wounds.

Introduction of the organisms into unusual body sites

E. coli is a normal resident in the large intestine but can cause disease if it gains entrance into unusual sites such as the urinary tract, wounds, or burns

1936

Ernest Fourneau discovered that the sulfanilamide portion contained antimicrobial activity

heavy metals

Even tiny quantities of metals, such as selenium, mercer, copper, and silver, can be very effective in inhibiting bacterial growth. Denature proteins

What conditions or events might facilitate this?

Failure of the host's normal defenses Introduction of the organisms into unusual body sites Disturbances in the normal microflora

microwave radiation

Falls at the long wavelength end of the electromagnetic spectrum. Absorbs water molecules then releases microwave energy to surroundings as heat.

Joseph Lister Antiseptic Surgery

Father of antiseptic Surgery 1st to use antiseptics on bandages and instruments to reduce post-operation infections.

plasmodial slime mold

Form multinucleate, amoeboid mass called a plasmodium which moves about slowly and phagocytes dead matter. Sometime a plasmodium stops moving and forms a fruiting body. Each fruiting body develops sporangia, sacs that produce spores. When spores are released, they germinate into flagellated gametes. Two gametes fuse lose their flagella and forms a new plasmodium.

crustacean

Generally aquatic arthropods that typically have a pair of appendages associated with each segment. Appendages include mouthparts, alas, walking legs, and appendages that aid in swimming or in copulation.

1935

Gerhard Domagk discovered prontosil, a red dye, that inhibits growth of many gram-positive bacteria

The common name for Rubella is ____ . It is caused by a highly contagious virus classified to Baltimore group ____ .

German measles ..... 4

What is the true cause of contagious disease?

Germs - Disease causing microbes

How are gnotobioic animals used to study the role of the normal flora?

Gnotobiotic animals are animals that are germfree or all of the microbes are known. These animals are born using aseptic techniques and kept in a sterile environment to prevent introduction of microbes. Specific microbes are then added to the environments in order to study the effects in a controlled manner.

What are previous theories of causes of contagious disease?

God's Punishment & Curses Miasma - Vapor of rotting organic material

funguslike protist

Have characteristics of fungi and some of animals. Fungus-like protists have cells walls similar to plants, which contain chitin, but possess the animal-like function of heterotrophy. They release spores into the air to reproduce and have the ability to move, although this might only happen once during a lifespan. Requiring a moist environment to survive, the two types of fungus-like protists are water mold and slime mold.

plantlike protist

Have chloroplasts, live in moist and sunny environments (include algae, euglenoids, diatoms, and dinoflagellates). Most have cell walls and one or two flagella. Considered the foundation of many aquatic food chains, responsible for over forty percent of photosynthesis that occurs in salt and fresh bodies of water, as well as essential to the production of oxygen in the atmosphere.

mastigophoran

Have flagella, a few species are free-living in either fresh or salt water, but most live in symbiotic relationships with plants or animals. A subphylum of protozoa, including all those that have one or more flagella throughout most of their life cycle, and a simple, centrally located nucleus; many are parasitic in both invertebrates and vertebrates, including humans.

insect

Have three body regions- head, thorax, and abdomen- three pairs of legs, and highly specialized mouthparts. Some have specialized mouthparts for piercing skin and for sucking blood, and can inflict painful bites. Vectors for spreading disease.

arachnid

Have two body regions- a cephalothorax and an abdomen- four pairs of legs, and mouthparts that are used in capturing and tearing apart prey. They include spiders, scorpions, ticks, and mites.

club fungi

Includes mushrooms, toadstools, rusts, and smuts. The rusts and smuts parasitize plants and cause significant crop damage. Have club shaped sexual structures called basidia from which the name Basidiomycota is derived. In a typical basidiomycete life cycle, sexual spores called basidiospore germinate to form separate mycelia, and cells of mycelia unite into dikaryotic forms.

How viruses cause pathogenic effects in host cells

Inclusion bodies: nucleic acids and proteins not yet assembled into viruses, masses of viruses, or remnants of viruses Retroviruses & oncoviruses: integrate into host chromosomes and remain in cells indefinitely Can cause agglutination of erythrocytes

identify each stage of infectious disease by name and relate each to the signs and symptoms and to activities of the pathogen

Incubation Period - No signs or symptoms Prodromal Phase - Vague symptoms Invasive phase - Most severe signs and symptoms. Decline phase - Declining signs and symptoms. Convalescence phase - Very few or no signs and symptoms.

Orthomyxoviridae family contains ____ viruses. Their viral genome is made of ____ .

Influenza ..... 6-8 pieces of (-) ssRNA

dyes

Interfere with cell replication by causing mutations in DNA. Methylene Blue inhibits growth of some bacteria. Crystal Violet blocks cell wall synthesis.

The scientific naming of virus is governed by the ____ .

International Committee on Taxonomy of Viruses

systematic disease

Invade internal organs and cause significant destruction.

bacteriostatic

Is a biological or chemical agent that stops bacteria from reproducing, while not necessarily killing them otherwise.

woronin body

Is a peroxisome-derived, dense core microbody with a unit membrane found near the septae that divide hyphal compartments in filamentous Ascomycota. When a hyphen cell ages or is damaged, the woronin body moves to and blocks the pore so that materials from the damaged cell cannot enter a healthy cell.

bactericidal

Is a substance that kills bacteria. Includes disinfectants, antiseptics, or antibiotics.

parasite

Is an organism the lives at the expense of another organism called the host. Vary in the degree of damage they inflict on their hosts. Those that cause diseases are called pathogens. An organism that lives off or in another organism, obtaining nourishment and protection while offering no benefit in return.

decimal reduction time

Is the length of time needed to kill 90% of the organisms in a given population at a specified temperature.

Hydrostatic Pressure

Is the pressure exerted by standing water in proportion to its depth.

Wendell Standley

Isolated virus particles

Why would pathogenesis be relatively rare, and not always in the best interest of the pathogen?

It's not in the best interest because if they damage or kill the host, their environment will be negatively affected and they may not be able to survive anymore.

Sterilization

Killing all Cells, Spores, & Viruses

Where do microorganisms come from?

Life comes from Live, not spontaneous generation

water mold

Live in shallow or damp places; can exist as decomposer or parasite; as a mold, it can be harmful if found in gardens and farms, detrimental to potatoes, corn and cabbage and can harm a host as a parasite; looks like a combination of fuzz and threads. Produce flagellated spores called zoospores during asexual reproduction and large motile gametes during sexual reproduction. The most prominent phase of their life cycle consists of diploid cells from the union of gametes.

What is a Microorganism?

Living organisms that are microscopic in size

disinfection

Means reducing the number of pathogenic organisms on objects or in materials so that they pose no threat of disease. Disinfectants are applied to inanimate objects and agents called antiseptics are applied to living tissue.

The common name for Rubeola is ____ . It is caused by a highly contagious virus that has ____ genome type.

Measles ..... (-) ssRNA

protist

Members of the Kingdom Protista, are a diverse assortment of organisms that are unicellular, eukaryotic organisms with cells that have true nuclei and membrane enclosed organelles. Unicellular organisms that don't possess enough characteristics to be defined as purely plant or animal. They are important because: 1. They are a key part of food chains 2. Can be economically beneficial or detrimental 3. Eutrophication 4. Some are parasitic

reactions that affect membranes

Membrane contain porteins, but they also contain lipids and thus can be disrupted by substances that dissolve lipids. Surfactants are soluble compounds that reduce surface tension, just as soaps and detergents break up grease particles in dishwater. They include alcohols, detergents, and quaternary ammonium compounds. Phenols dissolve lipids and also denature proteins. Detergents solutions also called wetting agents are often used with other chemical agents to help the agent penetrate fatty substances.

filter paper method

Method of evaluating chemical agent. Uses small filter paper disks, each soaked with a different chemical agent. The disks are placed on the surface of an agar plate that has been inoculated with a test organism. After incubation, a chemical agent that inhibits growth of a test organism is identified by a clear area around the disk where the bacteria have been killed.

What is Germ Theory?

Microbes invade other microorganisms and cause disease

Capnophiles

Microbes that grow better at high CO2 concentrations

How do microorganisms cause disease?

Microorganisms produce toxins

amebozoa

Move by means of pseudopodia. A few have flagella at some stage in their life cycle. They feed mainly on other microorganisms, including other protozoa and small algae. Soe inhibit the human intestinal tract and most form cysts that help them withstand adverse conditions. Include protists that are distinguished by possessing pseudopods. Pseudopods are temporary cytoplasmic projections of the cell membrane that are used for locomotion and/or feeding.

reactions that affect proteins

Much of a cell is made of protein, and all its enzymes are proteins. Alternation is called denaturation. Any agent that denatures proteins prevents them from carrying out their normal functions. Denaturation is bactericidal if it permanently alters the protein so that the protein's normal state cannot be restored. Denaturation is bacteriostatic if it temporarily alters the protein, and the normal structure can be recovered. Reactions that denature proteins include hydrolysis, oxidation, and the attachment of atoms or chemical groups.

schizogony

Multiple fission in which one cell gives rise to many cells, all of which are ineffective. Asexual reproduction by multiple fission, found in some protozoa, especially parasitic sporozoans.

Polumyxins

Narrow: gram-negative

Isoniazid

Narrow: myobacteria

Streptomycin

Narrow: myobacteria and gram-negative

Tobramycin

Narrow: myobacteria and gram-negative

roundworm

Nematodes share many characteristics with the flatworms, but they have a pseudocoelem, a primitive, fluid-filled body cavity that lacks the complete lining found in higher animals. Have cylindrical bodies with tapered ends and are covered with a thick protective cuticle. Contractions of strong muscles in the body wall exert pressure on the fluid in the pseudocoelem and stiffen the body. Breeding is enhanced by chemical attractants released by females that attract males.

Are Viruses living organisms?

No

What is the difference between the normal flora (microflora) and the microbiome?

Normal flora (microflora): Organismal level; what the bacterial level and what they're doing; can be easily studied Microbiome: Not really looking at organisms, but looking at genes in environment; neither beneficial or harmful characteristics & looking at microbes association with host. Pulling out microflora and looking at their genes; can look at pathways based on genes; expanding to gene level now in studies.

slime mold

Often seen on decaying plant life or trees, these protists sustain on bacteria and other microorganisms that appear on rotting plants under wet conditions; the two types, plasmodial and cellular, can appear in a range of colors. Most are saprophytes.

How virulence of a pathogen can be increased based on its host

Organisms freshly discharged from an infected individual are more virulent than those from a carrier who shows no signs of disease Animal passage: rapid transfer of the pathogen through animals of a species susceptible to infection by that pathogen. Human populations (influenza)

saprophyte

Organisms that feed on dead or decaying matter.

reactions that affect other cell components

Other cell components affected by chemical agents include nucleic acids and energy producing systems. Alkylating agents can replace hydrogen on amino or alcohol groups in nucleic acids. Certain dyes interfere with cell wall formation.

strong visible light

Oxidation of light sensitive materials.

facultative parasite

Parasites that are normally free living but they can obtain nutrients from a host.

temporary parasite

Parasites that feed on and then leave their hosts.

accidental parasite

Parasites that invade an organism other than their normal host.

ectoparasite

Parasites that live on the surface of other organisms such as ticks and lice. A parasite that lives on or in the skin but not within the body.

endoparasite

Parasites that live within the bodies of organisms such as protozoa and worms. A parasite that lives in the internal organs or tissues of its host.

obligate parasite

Parasites that must spend at least some of their life cycle in or on a host.

permanent parasite

Parasites that remain in or on a host once that have invaded it.

What are the possible outcomes of a symbiotic relationship?

Parasitism, mutualistic relationship, commensalism, or antagonistic

Characteristics of endotoxins

Part of the cell wall and are released into host tissues (sometimes in large quantities) from gram-negative bacteria often when they divide or die Relatively weak except in large doses Contain LPS (lipopolysaccharide) Relatively stable molecules that do not display affinities for particular tissues Nonspecific effects such as fever or a sudden drop in blood pressure Cause tissue damage in diseases

1910

Paul Ehrlich used Salvarsan to treat syphilis

Hepatitis A virus is classified to the ____ family, while hepatitis C virus is classified to the ____ family.

Picornaviridae ..... Flaviviridae

Examples of virulence factors used by bacteria to cause infection and disease

Pili for adhesion to the cells and tissues Enzymes that help in evading host defenses or protect the organism from host defenses Toxins that can directly cause disease

flatworm

Platyhelminthes are primitive worms usually no more than 1 mm thick. Lack a coelom, a cavity that lies between the digestive tract and the body wall in higher animals. Most are hermaphroditic, each individual having both male and female reproductive. Parasitic organisms such as the flukes and tapeworms have highly specialized reproductive systems.

chitin

Polysaccharide also found in the exoskeleton of arthropods such as ticks and spiders.

What are the beneficial roles of the normal flora/microbiome?

Probiotics through food: reduce anxiety and depression Gut microbiome: influences production of stress hormones by the brain

pasteurization

Process invented by Pasteur to destroy organisms that caused wine to sour, does not achieve sterility but does kill pathogens.

cellular slime mold

Produce pseudo plasmodia, fruiting bodies, and spores with characteristics that are quite different from those of plasmodial slime molds. A pseudoplasmodium is a slightly motile aggregation of cells. It produces fruiting bodies, which in turn produce spores. The spores germinate into ameboid phagocytic cells that divide repeatedly producing more independent amoeboid cells.

How viruses can be productive or abortive

Productive: viruses enter a cell and produce infectious offspring. Abortive: viruses enter a cell but are unable to express all their genes to make infectious offspring

Single-Celled Eukaryotes

Protists

Side effect of Rifampin

Red man syndrome and red/orange urine

Sanitation

Reducing microbial population to safe levels in the environment

host specificity

Refers to the range of different hosts in which a parasite can mature.

use-dilution test

Uses standard preparations of certain test bacteria. A broth culture of one of these bacteria is coated onto small stainless steel cylinders and allowed to dry. Each cylinder is then dipper into one of several dilutions of the chemical agent for 10 minutes, removed, rinsed with water, and placed in a tube of broth. The tubes are incubated and than observed for the presence or absence of growth.

soaps and detergents

Remove microbes, oily substances, and dirt. Mechanical scrubbing greatly enhances their action. Soaps contain alkali and sodium and will kill many species. Many pathogens that survive washing with soap can be killed by disinfectant applied after washing. Detergents, when used in weak concentrations in wash water, allow the water to penetrate into all crevices and cause dirt and microorganisms to be lifted out and washed away. Cationic detergents are used to sanitize food utensils. Many are quaternary ammonium compounds which have four organism groups attached to a nitrogen atom. One problem with quotes is that their effectiveness is decreased in the presence of soap, calcium, or magnesium. Lower surface tension, make microbes accessible to other agents.

Disinfection

Remove pathogens from inanimate surfaces

Antisepsis

Remove pathogens from tissue surfaces

osmotic pressure

Removes water from microbes.

The most common cause of "common cold" is a type of viruses called ____ . They are classified to the ____ family, and their genome replication involves a ____ intermediate.

Rhinoviruses ..... Picornaviridae ..... (-) ssRNA

Emile Roux & Alexandre Yersin

Showed diphtheria from diphtheria pathogen causes diphtheria, and used antibody against diphtheria toxin to cure 300 disease children -Diphtheria pathogen - Corynebacterium diphtheriae -Alexandre Yersin idenfified the plague pathogen - Yersinia pestis

phenol coefficient

Since lester introduced phenol (carbolic acid) as a disinfectant in 1867, it has been the standard disinfectant to which other disinfectants are compared under the same conditions. A disinfectant with phenol coefficient of 1.0 has the same effectiveness as phenol. A coefficient less than 1.0 means that its less effective than phenol, a coefficient greater than 1.0 means that its less effective than phenol. The phenol coefficient can be determined by the following steps: (page 344) -The measure of the disinfecting power of a substance that is determined by dividing the figure indicating the degree of dilution of the disinfectant that kills a microorganism within a given time by that indicating the degree of dilution of phenol killing the microorganism under similar conditions -The phenol coefficient is a measure of the disinfecting power of a germicidal solution in relation to phenol. To calculate for phenol coefficient, the number indicating the degree of dilution of the disinfectant in which it kills the microorganism within a given time (i.e. in 10 minutes but not in 5 minutes) is divided by the number indicating the degree of dilution of phenol in which the latter kills the microorganism in the same period of time and under the same conditions.

Protists with Chloroplasts

Single-Celeed Algae

acids and alkalis

Soap is a mild alkali, and its alkaline properties help destroy microbes. A number of organic acids lower the pH of materials sufficiently to inhibit fermentation. Several are used as food preservatives. Acids lower ph and denature proteins. Alkalis raise ph and denature proteins.

Characteristics of exotoxins

Soluble substances secreted into host tissues More powerful; produced by several gram positive and a few gram negative. Most are polypeptides (denatured by heat, UV light, chemicals such as formaldehyde) Some are enzymes and affect by toxemia (hemolysins) Some are leukocidins (toxemia) that damage or destroy WBCs (neutrophils and macrophages) Many have a special attraction for particular tissues

Limitations to Koch's postulates

Some bacteria have fastidious nutritional requirements or special needs for growth Some viruses cannot be grown on artificial media and must be grown in living cells Not always easy to obtain pure culture (older times specifically) Different degrees of varying symptoms

What role do virulence factors play in pathogenesis?

Virulence factors (structural or physiological factors) help organisms cause infections and disease. Contribute to pathogenesis

parasitology

Study of parasites.

Louis Pasteur

Swan-Neck Flask Experiments -Growth of microorganisms in nutrient broth is due to pre-existing microorganisms

Microbiology

The Study of Microorgansims

dimorphism

The ability of an organisms to alter its structure when it changes habitat.

mechanisms for evading host defense mechanisms

The adjustment of parasites and hosts to each other is closely related to the host's defense mechanism: 1.Encystment, the formation of an outer covering that protects against unfavorable environmental conditions. These resistant cyst stages also sometimes provide a site for internal reorganization of the organisms and cell division, help attach a parasite to a host, or serve to transmit a parasite from one host to another. 2. Changing the parasite's surface antigens (molecules that elect immunity) faster than the host can make new antibodies (molecules that recognize and attack antigens). 3. Causing the host's immune system to make antibodies that cannot react with parasite's antigens. 4. Invading host cells, where the parasites are out of reach of host defense mechanisms.

How does our body fight off infectious disease?

The body has an immune system that fights off infectious disease, lead to immunology.

sterilization

The killing or removal of all microorganisms in a material or on an object. There are no degrees of sterility- sterility means that there are no living organisms in or on a material. When properly carried out, procedures ensure that even highly resistant bacterial endospores and fungal spores are killed.

ciliate

The largest group of protozoans, have cilia over most of their surfaces. Cilia have a basal body near their origin that anchors them in the cytoplasm and enables them to extend from the surface of the cell, allows organisms to move. Undergo conjugation.

filtration

The passage of a material through a filter or training device. Mechanically removes microbes

What contributes to the relative pathogenicity and virulence of a pathogen?

The pathogen's ability to invade a host, multiply in the host, and avoid being damaged by the host's defenses. Some cause disease upon entering the host, others cause disease only in rare instances and usually only in hosts with poor defenses. (number of infectious organisms that enter the body)

thermal death point

The temperature that kills all the bacteria in a 24 hour old broth culture at neutral pH in 10 minutes.

thermal death time

The time required to kill all the bacteria in a particular culture at a specified temperature.

How do viruses cause disease?

They can replicate only once they have attached to cells, and then penetrated specific host cells. Once in cells, they can cause observable changes (cytopathic effect CPE)

How can the normal flora lead to opportunistic infections?

They do not typically cause disease, but can do so under certain conditions. They take advantage of particular opportunities to cause disease.

radiation

Ultraviolet light, ionizing, microwave, and strong visible light radiation can be used to control microorganisms and ro preserve foods

Anton von Leevwenhook

Used microscopes to describe living microorganisms

reactions that affect viruses

Viruses can cause infections and must be controlled. Control of viruses requires that they can be inactivated- that is rendered permanently incapable of infecting or replicating in cells. Inactivation can be affected by destroying either the viruses nucleic aid or proteins. Alkylating agents act as chemical mutagens- they alter DNA or RNA. If the alteration prevents the DNA or RNA from directing the synthesis of new viral particles, the alkylating agents are effective inactivators.

hermaphroditic

When an organism has both male and female reproductive systems and both are functional.

alcohols

When mixed with water, alcohols denature protein. They are also lipid solvents and dissolve membranes. Ethyl and isopropyl can be used as skin antiseptics.. It disinfects but does not sterilize skin because it evaporates quickly and stays in contact with microbes for only a few seconds. Denature proteins when mixed with water.

helminth

Worms are bilaterally symmetrical- that is they have left and right halves that are mirror images. Has a head and tail end, and its tides are differentiated into three distinct tissue layers: ectoderm, mesoderm, and endoderm.

ionizing radiation

X rays and Gamma rays (have short wavelengths) are forms of this, and they were named because it can dislodge electrons from atoms, creating ions. Kill microorganisms and viruses, damages DNA and produces peroxides which act as powerful oxidizing agents in cells.

Can we cure an infectious disease by killing off, or stop growing the pathogen in patents?

Yes.

Can we prevent an infectious disease by killing off the pathogen?

Yes.

bread mold

Zygomycota, or conjugation fungi, have complex mycelia composed go hyphae with chitinous walls. Some produce spores that will produce new hyphae. Sometimes short branches of the hyphae of two different strains, called plus and minus strains, grow together. This joining of hyphae gave rise to the name conjugation fungi.

Coagulase

a bacterial enzyme that accelerates the coagulation (clotting) of blood

Antibiotic

a chemical substance produced by microbes which has the capacity to inhibit or destroy the growth of bacteria/other microbes

Disease

a disturbance in the state of health wherein the body cannot carry out all its normal functions

Direct Microscopic count

a measured volume of a bacterial suspension is placed within a defined area on a microscope slide

Streak Plate Method

a method of isolating a culture by spreading microorganisms over the surface of a solid culture medium

Pathogen

a parasite capable of causing disease in a host

Transposal of virulence

a pathogen is passed from its normal host to a new host species and then passed sequentially through many individuals of the new host species

Invasiveness

a pathogen's ability to invade and grow in host tissues

Prodromal phase

a short period during which nonspecific, often mild, symptoms such as malaise and headache sometimes appear.

Antimicrobial Agents

a special group of chemotherapeutic agents used to treat diseases caused by microbes

As electrons are passed from carrier to carrier, their energy changes. At which point in the chain, would you expect the energy of the electrons to be the highest? a) A b) B c) C d) D e) E

a) A

Substrate level phosphorylation during glycolysis refers to the transfer of phosphate groups from: a) ATP to glucose b) 1,3 diphosphoglyceric acid to ADP c) phosphoenolpyruvic acid to ADP d) ATP to ADP

a) ATP to glucose

How is ATP formed by chemiosmosis? a) Charge difference of outer and inner membrane gives motive force to generate ATP b) Nitrates are used as their final electron acceptor c) The last step involves H2O to be split into O2 d) All of the metabolites enter the Krebs cycle

a) Charge difference of outer and inner membrane gives

During glycolysis, electrons are initially transferred to: a) NAD+ b) FAD c) NADP d) H2O

a) NAD+

Which of the following is true about glycolysis? a) The net yield of ATP is two ATPs for each molecule of glucose. b) It provides cells with a relatively large amount of energy. c) Four molecules of ATP are used in the initial phosphorylation steps. d) The ATP that is used up during glycolysis is not considered in calculating the net yield of ATP.

a) The net yield of ATP is two ATPs for each molecule of glucose.

Competitive inhibition of enzymes occurs when the inhibitor: a) binds to the active site of the enzyme. b) binds to the allosteric site of the enzyme. c) inhibitor changes the shape of the enzyme. d) inhibitor is acted upon by the enzyme.

a) binds to the active site of the enzyme.

The green sulfur and purple sulfur bacteria are capable of: a) carrying out photosynthesis b) only obtaining energy from organic molecules c) bypassing glycolysis for the Krebs cycle d) metabolizing without enzymes

a) carrying out photosynthesis

The initial breakdown of glucose in a eukaryotic cell takes place in the _____. a) cytoplasm b) golgi c) nucleus d) cell membranes

a) cytoplasm

Photoautotrophs obtain energy from: a) light and use carbon dioxide as a carbon source b) organic molecules and use carbon dioxide as a carbon source c) inorganic substances and use carbon dioxide as a carbon source d) light and use organic substances as a carbon source

a) light and use carbon dioxide as a carbon source

A surfactant: a) lowers the surface tension at the bacterium's posterior end allowing Myxococcus to glide b) is metabolized to produce phosphoenolpyruvate c) forms channels thorugh the outer membrane d) emits light as it returns to its unexcited state

a) lowers the surface tension at the bacterium's posterior end allowing Myxococcus to glide

After a viral infection, the host cell may die and new virions are released. New virions then bind to new host cells and the cycle starts again. This mode of viral replication is called ____ .

active infection

Broad Spectrum

agents effective against both gram-positive and gram-negative bacteria

Narrow Spectrum

agents effective against small number of microbes

Alkaliphiles

alkali loving bacteria, are organisms that exist from pH 7.0 to 11.5 -grow optimally at pH above 8.5

Microbiome

all microbial species and their genes that inhabit the human body

Symbiosis

an association between two or more species

Hyaluronidase

an enzyme (spreading factor) that digests hyaluronic acid which normally holds cells of tissues together. This enzyme allows streptococci to pass between epithelial cells and invade deeper tissues

Host

any organism that harbors another organism

Toxin

any substance that is poisonous to other organisms

Microaerophiles

appear to grow best in the presence of a small amount of free oxygen -They grow below the surface of the medium in a culture tube at the level where oxygen availability matches their needs

Acidophiles

are acid loving organisms that grow best at pH of 0.1 to 5.4. -Lactobacillus

Adherence

attachment of bacteria to a host cell's surface

As electrons are passed from carrier to carrier, their energy changes. At which point in the chain, would you expect the energy of the electrons to be the lowest? a) A b) G c) C d) F e) E

b) G

During the metabolism of fats, the product of beta-oxidation enters: a) glycolysis b) Krebs cycle c) oxidative phosphorylation d) electron transport chain

b) Krebs cycle

The initial substrate molecule for the Krebs cycle is: a) pyruvic acid b) acetyl-CoA c) acetic acid d) butanediol

b) acetyl-CoA

A metabolic pathway that is involved in both breakdown and synthetic reactions is properly termed _____. a) catabolic b) amphibolic c) metabolic d) anabolic

b) amphibolic

The synthesis of DNA, in which small nucleotides are joined together to make a single large molecule would be most correctly described as being a/n ________ reaction. a) metabolic b) anabolic c) catabolic d) cytobolic

b) anabolic

Degradation reactions where large molecules are broken down into smaller molecule is referred to as: a) metabolism b) catabolism c) biosynthesis d) anabolism

b) catabolism

Sulfa drugs bind to the active site of the enzyme which normally converts para-amino benzoic acid (PABA) to folic acid, preventing the production of folic acid and, eventually purine synthesis. In this case, the sulfa drug is acting as a/an: a) allosteric inhibitor b) competitive inhibitor c) noncompetitive inhibitor d) uncompetitive inhibitor

b) competitive inhibitor

In photosynthesis, chemical energy is used to make organic molecules in the: a) light reaction b) dark reaction c) hydrolytic reaction d) photophosphorylation reaction

b) dark reaction

Pyruvic acid is metabolized in the absence of oxygen during the process of: a) glycolysis b) fermentation c) oxidation d) dark reactions

b) fermentation

In glycolysis, each molecule of glucose eventually produces ________ molecules of pyruvic acid. a) one b) two c) three d) four

b) four

Glucose is to photosynthesis as pyruvate is to: a) oxidative phosphorylation b) glycolysis c) fermentation d) Krebs cycle

b) glycolysis

All of the following are electron acceptors for anaerobic respiration, except: a) carbon dioxide b) oxygen c) nitrate ions d) sulfate ions

b) oxygen

In aerobic respiration, the final electron acceptor is: a) water b) oxygen c) sulfur d) coenzyme Q

b) oxygen

Factors that can induce the re-activation of a prophage into lytic cycle may include ____ .

bacteria host gaining abundant nutrients and bacteria host suffer DNA damage

Factors that can induce the bacteriophage into lysogenic cycle may include ____ .

bacteria host is starved of nutrients.

Penicillin and cephalosporin contain a structure called...

beta-lactam ring

Antibiotics of the rifamcin family...

bind to a bacterial RNA polymerase and inhibit RNA synthesis

Aminoglycoside antibiotics

bind to the bacterial 30S ribosome subunit and interfere with the translation of mRNA

Mutualism

both members of the association living together benefit from the relationship

Antagonism

both species harm each other

At which temperature do enzymes begin to denature? a) 20 degrees Celsius b) 30 degrees Celsius c) 40 degrees Celsius d) 50 degrees Celsius

c) 40 degrees Celsius

An enzyme-substrate complex forms when substrate binds to an enzyme at the enzyme's ______ site. a) catalytic b) allosteric c) operative d) active

d) active

How does concentration affect enzyme-catalyzed reactions? a) As the concentration of the product goes up the enzyme increases the rate it produces the product. b) Concentration does not affect enzyme-catalyzed reactions because they are irreversible. c) At chemical equilibrium, no net change in the concentration of the product or substrate occurs. d) The quantity of enzyme available usually controls the rate of a metabolic reaction.

c) At chemical equilibrium, no net change in the concentration of the product or substrate occurs.

Which one of the following pairs is mismatched? a) Alcohol - Fermentation b) Pyruvate - Glycolysis c) Carbon dioxide - Glycolysis d) Oxaloacetic acid - Krebs cycle

c) Carbon dioxide - Glycolysis

Which statement is true about enzymes? a) Enzyme catalyzed reactions would not go forward without their specific enzymes. b) Most enzymes catalyze several different reactions. c) Coenzymes are organic molecules while cofactors are inorganic molecules. d) An apoenzyme is a holoenzyme that is missing its cofactor.

c) Coenzymes are organic molecules while cofactors are inorganic molecules.

Which of the following is not a carrier molecule that carries hydrogen atoms or electrons in oxidative reactions? a) Cytochrome b) FAD c) Niacin d) NAD+

c) Niacin

Which of the following statements about enzyme inhibition is true? a) Most noncompetitive inhibitors bind to several different sites on an enzyme. b) Enzymes become less efficient as temperatures drop because they begin to denature. c) Noncompetitive inhibitors bind to a site other than the active site. d) Most human enzymes have an optimum temperature below normal body temperature.

c) Noncompetitive inhibitors bind to a site other than the active site.

The first step in protein metabolism is the breakdown of proteins into: a) nucleotides b) fatty acids c) amino acids d) coenzymes

c) amino acids

In the electron transport chain, the energy to make ATP comes directly from _____. a) FAD b) NADH c) both FAD and NADH d) neither FAD nor NADH

c) both FAD and NADH

Enzymes work by: a) lowering the energy of the reactants. b) raising the energy of the products. c) decreasing the activation energy of the reaction. d) increasing the activation energy of the reaction.

c) decreasing the activation energy of the reaction.

Oxidation is defined as the ________ while reduction is the ________ . a) gain of electrons, loss of protons b) loss of electrons, gain of protons c) loss of electrons, gain of electrons d) loss of protons, gain of protons

c) loss of electrons, gain of electrons

In algae, the dark reactions of photosynthesis occur in the: a) cell membrane b) matrix of the mitochondria c) stroma of the chloroplast d) nucleus

c) stroma of the chloroplast

Barophiles

can survive under extreme pressure and will rupture if exposed to normal atmospheric pressure

Facultative anaerobes

carry on aerobic metabolism when oxygen is present, but they shift to anaerobic metabolism when oxygen is present -Often found in intestinal and urinary tracts

Obligate anaerobes

carry out fermentation or anaerobic respiration and cannot survive in the presence of O2 -Grown near the bottom of tubes

Toxic dosage level

causes damage to the host

Varicella-zoster virus causes ____ in its first time infection outbreak. Replication of this virus depends on ____ .

chicken pox ..... DNA-dependent DNA polymerase

Psychrophiles

cold-living organisms that grow best at temperatures of 15 degrees Celsius to 20 degrees Celsius

Cytomegalovirus may cause ____ in pregnant women if its infection is not detected and treated. Replication of this virus depends on ____ .

congenital disorders ..... DNA-dependent DNA polymerase

Hepatitis B virus infection is spread by ____ .

contact with blood & body fluid

Persistent viruses

continued production of viruses over many months or years

The prokaryotic aerobic metabolism of glucose produces a total (net) of ________ molecules of ATP. a) 24 b) 30 c) 34 d) 38

d) 38

Which reaction takes place in the mitochondrial membrane? a) Glycolysis b) Fermentation c) Krebs cycle d) Electron transport chain

d) Electron transport chain

What is returned to chlorophyll in cyclic photophosphorylation that is not returned in non- cyclic photoreduction? a) ATP b) Light c) Energy d) Electrons

d) Electrons

Which statement about fermentation is true? a) All fermentation of pyruvic acid always results in the same end product. b) All fermentation of glucose begins with pyruvic acid as a substrate. c) The same fermentation reaction produces both wine and cheese. d) None of the above

d) None of the above

A holoenzyme consists of: a) an apoenzyme plus a cofactor b) an apoenzyme plus a coenzyme c) an protein and non-protein component d) all of the above

d) all of the above

Bioluminescent microbes: a) may have evolved to remove oxygen from the atmosphere b) are often beneficiaries of symbiotic relationships with a larger host, producing light in exchange for nutrients c) often have the enzyme luciferase which catalyzes the oxidation reaction that emits light d) all of the above

d) all of the above

Factors that affect the rate of enzyme catalyzed reactions include: a) temperature b) pH c) concentration of enzyme d) all of the above

d) all of the above

Each acetyl-CoA molecule will eventually produce ________ in the Krebs cycle. a) four pairs of electrons b) three molecules of NADH c) one molecule of GTP d) all of these choices

d) all of these choices

Chemiosmosis: a) forms ATP b) occurs in the cell membrane of prokaryotes c) uses a proton gradient to activate ATP synthase d) all the above

d) all the above

The electrons transferred from acetyl groups in the Krebs cycle are transferred to: a) NAD+ only b) FAD only c) neither NAD+ and FAD d) both NAD+ and FAD

d) both NAD+ and FAD

In fermentation reactions occurring in yeast to produce wine, two products of the reaction are __________ and _________. a) acid; hydrogen gas b) hydrogen gas; propionic acid c) ethyl alcohol; methane d) carbon dioxide; ethyl alcohol

d) carbon dioxide; ethyl alcohol

Chemoautotrophic bacteria obtain the energy they need from: a) the reactions of photosynthesis b) sunlight c) carbon dioxide in the atmosphere d) chemical reactions in their cytoplasm centered around the use of inorganic substances

d) chemical reactions in their cytoplasm centered around the use of inorganic substances

Animals (humans for example) are: a) photoautotrophs b) photheterotrophs c) chemoautotrophs d) chemoheterotrophs

d) chemoheterotrophs

Organisms that can use oxygen for metabolic reactions but can also function in an environment devoid of oxygen are termed _____. a) aerobes b) anaerobes c) aerophiles d) facultative anaerobes

d) facultative anaerobes

Organisms which get their carbon from other organisms are: a) autotrophs b) chemotrophs c) phototrophs d) heterotrophs

d) heterotrophs

Electron transport chain: a) involves transfer of O2 to electrons in the substrate b) results in a net consumption of ATP c) can be thought of as electrons acting as fish increasing in energy as they jump up a waterfall d) none of the above

d) none of the above

The end product of glycolysis is: a) fructose-1,6-diphosphate b) 1,3 diphosphoglyceric acid c) phosphoenolpyruvic acid d) pyruvic acid

d) pyruvic acid

In photosynthesis, light energy is used to: a) break down proteins b) phosphorylate ADP to form ATP c) synthesize carbohydrates d) two of these choices

d) two of these choices

Inhibition of Nucleic Acid Synthesis

differences between the enzymes used by bacterial and animal cells to synthesize nucleic acids

Noninfectious disease

diseases caused by any factor other than infectious organisms

Infectious disease

diseases caused by infectious agents such as bacteria, viruses, fungi, protozoa, and helminths

Streptokinase

dissolves blood clots

Aerotolerant anaerobes

do not utilize oxygen but can survive and grow in its presence -Lactobacillus

Viruses classified into Baltimore Group 1 have genome made of ____ . Their genome replication depends on ____ .

dsDNA ..... DNA-dependent DNA polymerase

Viruses classified into Baltimore Group 7 have genome made of ____ . Their genome replication depends on ____ .

dsDNA ..... DNA-dependent RNA polymerase + RNA-dependent DNA polymerase

Replication of human immunodeficiency viruses involves ____ intermediate, and ____ enzyme.

dsDNA ..... RNA-dependent DNA polymerase

Viruses classified into Baltimore Group 3 have genome made of ____ . Their genome replication depends on ____ .

dsRNA ..... RNA-dependent RNA polymerase

B-Lactamase

enzyme found in various bacteria that catalyze the breaking of the B-lactam ring in penicillins and cephalosporins

The beta-lactam ring attaches to the...

enzymes that cross-link peptidoglycans and prevent cell wall synthesis

Neutrophiles

exist from pH 5.4 to 8.0 -Most of the bacteria that cause disease in humans

The highest viral taxonomy level is ____ .

family

Enteroviruses may spread through ____ route. Although they can cause ____ , they are preventable by ____ .

fecal-to-oral ..... poliomyelitis ..... vaccination

Noroviruses are contagious pathogens that cause ____ . Their genome is ____ type, and they can spread through ____ .

gastroenteritis ..... (+) ssRNA ..... contaminated food & water

Herpes simplex virus 2 commonly causes ____ . Replication of these viruses depend on ____ .

genital herpes ..... DNA-dependent DNA polymerase

Especially effective against...

gram-negative bacteria which have an outer membrane

Cells in Distilled Water

have a higher osmotic pressure than their environment and gain water.

Thermophiles

heat-loving organisms that grow best at temperatures from 50 degrees Celsius to 60 degrees Celsius

Ebola viruses cause ____ . Due to the virion morphology, the family name of these viruses is ____ .

hemorrhagic fever ..... Filoviridae

Synchronous growth

hypothetical pattern of growth during the log phase in which all the cells in a culture divide at the same time

Failure of the host's normal defenses

individuals with weakened immune defenses are immunocompromised. (malnutrition, presence of another disease, advanced or very young age, treatment with immunosuppressants, physical/mental stress)

Communicable

infectious diseases that can be spread from one host to another

Epstein-Barr virus may cause ____ . It spreads mainly by ____ .

infectious mononucleosis ..... contaminated saliva

During lysogenic infection, a bacteriophage genome is ____ into host cell genome, and this stage of the bactriophage is called a ____ .

integrated ..... prophage

Lag Phase

intense activity preparing for population growth, but no increase in population

Cytocidal viruses

kill cells by causing enzymes from cellular lysosomes to be released or by diverting the host cell's synthetic processes, thereby stopping the synthesis of the host's proteins and other essential macromolecules

After a viral infection, the host cell may stay functioning as normal, and the viral genome in the cell stays dormant. This mode of virus life cycle is called ____ .

latency

Cells in Hyperosmotic Environments

lose water

Black hairy tongue caused by...

metronidazole (Flagyl)

Contamination

microbes are present

Resident microflora

microbes that are always found on the body, and are adapted to prevailing conditions

Transfer (transient) microflora

microbes that can be present under certain conditions in any of the locations where resident microflora are found. Exist there as long as favorable conditions exist

Acquisition of Resistance

microorganisms normally acquire antibiotic resistance by genetic changes

Parts of the body not normally occupied by normal flora

middle/inner ear, sinuses, internal eye, bone marrow, muscles, glands, organs, circulatory system, brain and spinal cord, ovaries and testes; blood, urine, semen

Infection

multiplication of any parasitic organisms within or on the host's body

MMR vaccine covers ____ , ____ , and ____ .

mumps ..... measles ..... rubella

Nonsynchronous growth

natural pattern of growth during the log phase in which every cell in a culture divides at some point during the generation time, but not simultaneously

Noncommunicable

not spread from one host to another

Latent viruses

occur from exposure at a younger age, but remain dormant until the immune system is vulnerable.

The quote on p407 describes pathogenesis as an unsuccessful attempt at symbiosis. What does this mean?

often times it results from the bacteria attempting to form a symbiotic relationship within a new human host. However, the pathogenesis occurs when the symbiotic relationship is unbalanced and one side begins to take from the other.

Parasitism

one organism (the parasite) benefits from the relationship, while the other organism (the host) is harmed by it

Facultative

organism that can survive with or without oxygen

Opportunistic infections

organisms that do not usually cause disease, but can under certain conditions. They take advantage of particular opportunities to cause disease

Normal microflora

organisms that live on or in the body but do not cause disease

Endotoxin

part of the cell wall and are released into host tissues from gram-negative bacteria, often when they divide or die

Acme

part of the invasive phase where the signs and symptoms reach their greatest intensity

Some viruses, after binding on host cell surface, can hijack cellular ____ process to gain entry into host cells, when this process's normal purpose is for cells to engulf & destroy microbes.

phagocytosis

Disruption of cell membrane function EXAMPLE

polymyxin

Disruption of cell membrane functions

polypeptide antibiotics act as detergents and distort bacterial cell membranes

Osmotic Pressure

pressure that must be applied to prevent osmotic movement across a selectively permeable membrane

Antiviral proteins

prevent a cell from becoming infected

Interferons and Immunoenhancers

produces by cells infected with a virus, they induce neighboring cells to produce antiviral proteins

Adhesins

proteins or glycoproteins found on attachment pili (fimbriae) and capsules

Stationary Phase

rate of cell growth equals rate of cell death caused by depleted nutrients and O2, excretion of organic acids and pollutants -Represented by a horizontal straight line on a graph

Virus host range is determined by existence of ____ , and ____ .

receptor proteins on cells that can bind the virus ..... cellular enzymes required for viral replication

Obligate aerobes

require O2 for cellular respiration -grow near the top of nutrient broth, where oxygen is freely exchanged

Inhibition of nucleic acid synthesis EXAMPLES

rifamycin (transcription) quinolones (DNA replication) metronidazole

During lytic cycle infection, a bacteriophage genome is being replicated by ____ process.

rolling circle replication

Inhibition of Protein Synthesis

selective toxicity, attacks bacterial cells without causing significantly damaging animal cells

Inhibition of cell wall synthesis

selectively damages bacterial and fungal cells

Parts of the body normally occupied by normal flora

skin, intestine, mouth, urogenital tract, and upper respiratory tract, nose, stomach, urethra, vagina, nose, sweat glands, large intestines (most microbes)

Exotoxin

soluble substances secreted into the host tissues

Viruses classified into Baltimore Group 2 have genome made of ____ . Their mRNA transcription depends on ____ .

ssDNA ..... DNA dependent RNA polymerase

Virulence factors

structural or physiological characteristics that help organisms cause infection and disease

Action as Antimetabolites

substances that affect the utilization of metabolites and prevent metabolic reactions -> enzymes

Therapeutic dosage level

successfully eliminates the pathogenic organism if the level is maintained

Action an antimetabolites EXAMPLES

sulfonilamide trimethoprim

Contagious

synonymous for communicable disease

Staining of teeth caused by...

tetracycline

Inhibition of protein synthesis EXAMPLES

tetracycline erthromycin streptomycin chloramphenicol

Selective Toxicity

the antimicrobial agent must harm the microbes without causing significant damage to the host

Pathogenicity

the capacity to produce disease

Colonization

the growth of microorganisms on epithelial surfaces, such as skin or mucus membranes or other host tissues

Invasive phase

the individual experiences the typical signs and symptoms of a disease

Virulence

the intensity of the disease produced by pathogens; varies among different microbial species

Alteration of Targets

the mutation alters the DNA such that the protein produced or target is modified and antimicrobial agents can no longer bind to the target

Cytopathic effect

the observable changes that viruses cause once inside a host cell

Obligate

the organism must have the specified environmental condition

Optimum pH

the pH at which an enzyme achieves maximum activity

Decline phase

the period of the illness during which the host defenses and the effects of treatment finally overcome the pathogen

Spectrum of Activity

the range of different microbes against which an antimicrobial agent acts

Animal passage

the rapid transfer of a pathogen through animals of a species susceptible to infection by that pathogen

Logarithmic growth

the rapidly growing exponential growth phase of a cell culture. During this bacterial growth phase, the number of new cells appearing are proportional to the population.

Disturbances in the normal microflora

thriving populations of normal microflora compete with pathogenic organisms and in some instances actively combat their growth (microbial antagonism)

Convalescence period

tissues are repaired, healing takes place, and the body regains strength and recovers. The individual no longer has symptoms of the disease

Baltimore classification of viruses is based mainly on ____ , and ____ .

type of genome in virion ..... mechanism of viral genome replication & mRNA transcription

The viruses that cause smallpox are called ____ . There is no natural smallpox infection since 1980 due to successful global ____ effort.

variola major & variola minor ..... vaccination

A viral nucleocapsid is made of ____ , and ____ .

viral genome ..... viral capsid

A virion is made of ____ , ____ , and possibly ____ (depending on species).

viral genome ..... virus capsid ..... viral envelope

a complete virus particle capable of infection.

virion

Mesophiles

which include most bacteria, grow best at temperatures between 25 degrees Celsius and 40 degrees Celsius -Human pathogens grow are included in this category -Inadequate heating during canning or in pasteurizing may leave such organisms alive and therefore able to spoil food