Exam 1: Ch 1: Intro to Microbes

Question 1

Scientific method

Answer 1

Observations → hypothesis → predictions → test → hypothesis either supported or rejected (rejected = back to hypothesis and repeat) (supported = start all over again w/new info)

Question 2

Spontaneous generation

Answer 2

belief that some forms of life could arise from vital forces present in nonliving or decomposing matter; belief that living organisms didn’t necessarily come from living organisms all the time
(hay + cheese = mouse in barn); invisible forces lead to creation of life

Question 3

Abiogenesis

Answer 3

“beginning in the absence of life”; supports spontaneous generation

Question 4

Biogenesis

Answer 4

“beginning with life”; all living things arise from other living things; proved by Redi and Pasteur

Question 5

Germ theory of disease

Answer 5

diseases are caused by germs and not b/c you have sinned or done something wrong; Pasteur and Koch contributed to this

Question 6

Koch’s postulates

Answer 6

(4 steps) - everyone has to have the bacteria, have to isolate it and put it back into an organism and have same bacteria
−1) the suspected pathogen must be found in every case of the disease
−2) suspected pathogen must be isolated in pure culture
−3) inoculation of a sample of the culture into a health, susceptible animal must produce the same disease
−4) suspected pathogen must be recovered from the inoculated animals

Take pathogen out of dead mouse, isolate in culture, inoculate new mouse, mouse dies, take out pathogen, must be the same one

Question 7

Organelles

Answer 7

small, double-membrane-bound structures that perform a specific function in a cell (includes nucleus, mitochondria and chloroplasts)(ribosome is only non-membrane bound organelle)

Question 8

Taxonomy

Answer 8

grouping of organisms

Question 9

Nomenclature

Answer 9

naming; assignment of scientific names to various taxonomic categories and individual organisms

Question 10

Binomial nomenclature

Answer 10

uses 2 names: genus (capital) and species (lowercase)

Question 11

Classification

Answer 11

orderly arrangement of organisms into a hierarchy of taxa

Question 12

Macromolecules

Answer 12

4 main ones = carbs, lipids, proteins, nucleic acids

Question 13

Monomers

Answer 13

subunits of macromolecules

Question 14

Polymers

Answer 14

chains of various lengths made up of monomers

Question 15

Carbohydrates

Answer 15

fast energy for cell

Question 16

Polysaccharides

Answer 16

contribute structural support and protection; serve as nutrient and energy stores

Question 17

Agar

Answer 17

polysaccharide used in preparing solid culture media for microbes

Question 18

Peptidoglycan

Answer 18

polysaccharide linked to peptide fragments; found in bacterial cell walls (not archaeans; remember – if peptidoglycan found in cell wall = always bacteria, period)

Question 19

Lipopolysaccharide

Answer 19

complex of lipid and polysacc responsible for symptoms of fever and shock (TSS)

Question 20

Glycocalyx

Answer 20

outer surface of many cells; functions in attachment or as a receptor that receives external stimuli

Question 21

Lipids

Answer 21

important for long term storage of energy ad protection in the cell; found in membrane of cell

Question 22

Membrane lipids

Answer 22

naturally assume single and double layers (bilayers) which contribute to their biological significance in membranes

Question 23

Hydrophilic (of lipid)

Answer 23

water loving region from the charge on the phosphoric acid-alcohol “head” of the molecule; outside the membrane

Question 24

Hydrophobic (of lipid)

Answer 24

water fearing region inside the long, uncharged “tail” of the molecule formed by fatty acids; inside the membrane

Question 25

Proteins

Answer 25

predominant organic molecule in cells

Question 26

Amino acids

Answer 26

building blocks of proteins; all have a central core & a functional group (determines its role)

Question 27

Peptide

Answer 27

molecule composed of short chains of amino acids

Question 28

Polypeptide

Answer 28

contains an unspecified # of amino acids but usually has >20

Question 29

Primary structure (1 degree) of proteins

Answer 29

the type, number and order of amino acids in the chain

Question 30

Secondary structure (2 degree) of proteins

Answer 30

arises when functional groups exposed on the outer surface of molecule interact by forming hydrogen bonds → alpha helix & beta-pleated sheet; hydrogen bonds formed btwn close amino acids

Question 31

Tertiary structure (3 degree) of proteins

Answer 31

created by additional bonds btwn functional groups; where there is bonding btwn distant amino acids

Question 32

Quaternary structure (4 degree) of proteins

Answer 32

formed when more than one polypeptide forms a large multiunit protein; multiple subunits of tertiary structures; binding together of multiple tertiary structure proteins; not all proteins get to this state

Question 33

Enzymes

Answer 33

protein catalysts for chemical reaction in cells; biological catalysts that lower activation energy; tools of the cell; 1 enzyme for 1 substrate

Question 34

Antibodies

Answer 34

complex glycoproteins w/specific attachment regions for bacteria, viruses, and other microorganisms

Question 35

Native state of protein

Answer 35

the functional 3D form

Question 36

Denaturing

Answer 36

a protein becomes denatured if the protein structure is disrupted for some reason; becomes nonfunctional; disruptive agents: heat, alcohol, acid, disinfectants

Question 37

DNA

Answer 37

contains the special coded genetic program w/detailed and specific instructions for each organism’s heredity

Question 38

RNA

Answer 38

“helper” molecules responsible for carrying out DNAs instructions and translating the DNA program into molecules

Question 39

Microbiology

Answer 39

area of biology that involves living things (microbes and microorganisms) that require magnification to be seen by the human eye

Question 40

Evolution

Answer 40

changes that occur in organisms as they adapt to their environments over time

Question 41

Theory (from a scientific perspective)

Answer 41

a thoroughly studied, well established, natural phenomenon that has undergone years of testing w/out being disproven

Question 42

Pathogen

Answer 42

microbes that can cause various types of diseases or other health problems

Question 43

Subunit

Answer 43

monomers; bind into chains called polymers thru polymerization

Question 44

Importance of microbio

Answer 44

it’s the most important organism on earth; gives rise to everything − Infectious disease control − Nitrogen fixation – w/out nitrogen, we don’t have proteins or DNA − Microbes shape our planet – the main forces that drive the structure and content of the soil, water and atmosphere o Produce gases (CO2, NO, CH3) that regulate the temperature of the earth o Underground community of microbes influence weathering, mineral extraction and soil formation o Found in earth’s crust, polar ice caps, oceans, and bodies of plants and animals o Live in places where other organisms cant survive & are most diverse group of organisms o Cyanobacteria – the original way we have O2 on earth − Food – fermented foods are very important; we cant wash microbes off of foods and microbes can attack foods (bread, cheese, milk products, fermented veggies, alcohol, spoilage/preservatives, plant and animal disease) − Antibiotics – kill off certain microbes; microbes are also super easy to work with, no one cares if they die, and they give us a lot − Molecular biology – gene cloning, genetic engineering, metabolism research

Question 45

Prokaryotic

Answer 45

no nucleus and organelles − Relatively simple in structure but complicated in function − All bacteria are prokaryotes – different bacteria have different adaptations − 1000x smaller − Always single cellular

Question 46

Eukaryotic

Answer 46

nucleus and organelles − More complicated; has membrane bound organelles; has a membrane surrounded by a membrane − 1000x larger − Can be single cellular or multi cellular

Question 47

Fundamental characteristics of a cell for living organisms

Answer 47

1. Energy from the environment (photosynthesis, consumer, etc) 2. Reproduction via DNA 3. Evolve as a group (if the environment changes) 4. Homeostasis (keep balance in the environment) 5. At least one cell

Question 48

Types of microorganisms (6)

Answer 48

helminthes, insects, protists, viruses, fungi, bacteria; living groups of microorganisms involve all of the above except viruses

Question 49

Viruses

Answer 49

non living − Don’t always reproduce via DNA – cant replicate w/out using host replication machinery − Don’t need energy b/c they use us (host) to make it − Do evolve − No homeostasis/ability to control their structure or surroundings − Don’t have cell structures (not a cell) don’t all have membrane, don’t have ribosomes or cytoplasm − Because they are non living, they ARENT INCLUDED in the same taxonomical system as living organisms (they aren’t in one of the 3 domains)

Question 50

Taxonomy

Answer 50

grouping of organisms Domain(3) → Kingdom(6) → Phylum → Class → Order → Family → Genus → Species Did King Philip Come Over For Good Soup Kingdoms are inclusive, Species are exclusive (as you go down, it narrows)

Question 51

Domains (3)

Answer 51

based on genetic similarities/off of rRNA sequence info − Archaea – cells that live in extreme environments (high salt, heat, etc); NO peptidoglycan, no organelles − Bacteria – true bacteria, peptidoglycan in cell wall, no organelles (if you have peptidoglycan in cell wall, you are bacteria – period) − Eukarya – have nucleus and membrane bound organelles (ER, Golgi, mito/chloro); hosts

Question 52

Kingdoms (6)

Answer 52

``` − Bacteria (domain: bacteria) − Archaea (domain: archaea) − Protista (domain: eukarya) − Plantae (domain: eukarya) − Fungi (domain: eukarya) − Animalia (domain: eukarya) ```

Question 53

4 ways microbes have shaped our planet

Answer 53

1. Changing the earth’s atmosphere from one w/out O2 to one with O2 2. Formation of the ozone due to use of O2 for aerobic respiration 3. Photosynthesis (accounts for >70% of the earths’ photosynthesis → majority of O2 in atmosphere) 4. Temperature – maintenance and regulation

Question 54

3 elements present in all 4 of the biological macromolecules

Answer 54

carbon, hydrogen, oxygen

Question 55

Ferdinand Cohn

Answer 55

discovered heat-resistant bacterial endospores, which were the reason that heat would sometimes fail to eliminate all microorganisms