Fall sesh. midterm

Question 1

What is the first postulate of Koch?

Answer 1

1. The suspected pathogen must be present in all case of the disease, and absent from all healthy animals.

Question 2

What is Koch’s second postulate?

Answer 2

The suspected pathogen must grow in pure culture

Question 3

What is Kochs’ third postulate?

Answer 3

Cells from a pure culture of the suspected pathogen must cause disease in healthy animals

Question 4

what is the fourth postulate?

Answer 4

The suspected pathogen must be re isolated and shown to be the same as the original.

Question 5

metabolism

Answer 5

the take up of nutrients from the environment and transform them into new cell material and waste products.

Question 6

growth

Answer 6

to increase in cell number from cell division

Question 7

evolution

Answer 7

descent with modification

Question 8

motility

Answer 8

self propulsion, allows cells to move away from danger or unfavorable conditions and to exploit new resources or opportunities

Question 9

differentiation

Answer 9

modified cells for specialized growth, dispersal, survival, in general function

Question 10

cells can be viewed as?

Answer 10

biochemical catalysts, carrying out the chemical reactions that constitute metabolism

Question 11

what are properties of all cells?

Answer 11

compartmentalization and metabolism, growth,, evolution,

Question 12

what are properties present in particular cells

Answer 12

motility, differentiation, communication

Question 13

how do cells function genetically?

Answer 13

the cell replicates DNA and then processes it to form the RNAs and proteins needed for maintenance and growth under good conditions,

Question 14

What two main events make up the DNA process?

Answer 14

The production of RNAs(transcription) and the production of proteins(translation)

Question 15

Why are the genetic and catalytic functions of a microbial cell important?

Answer 15

cells coordinate their catalytic and genetic functions to support cell growth

Question 16

what is a population?

Answer 16

a group of cells derived from a single parental cell by successive cell divisions

Question 17

what is the definition of an ecosystem?

Answer 17

all the living organisms, together with the physical and chemical components of the environment.

Question 18

what are some examples of ecosystems?

Answer 18

aquatic- oceans, ponds, lakes, streams, ice/hot springs, and terrestrial, soils, surface and deep, and plants and animals could also be ecosystems.

Question 19

What are key molecular processes in cells?

Answer 19

Replication, transcription, and translation

Question 20

what is LUCA? What major lineages arose from LUCA?

Answer 20

last universal common ancestor, and bacteria, archaea, and eukarya

Question 21

How old is earth? when did the first cellular forms appear?

Answer 21

4.6 billion years old, at 3.8 billion years

Question 22

how do we reconstruct the sequence of organisms that appeared on Earth?

Answer 22

scientists can reconstruct evolutionary transitions by using biomarkers, specific molecules that are unique to particular groups in present day microorganisms.

Question 23

who developed sterilization?

Answer 23

Pastuer

Question 24

what is an enrichment culture?

Answer 24

its a culture of a microorganisms isolated from natural samples using highly selective techniques of adjusting nutrient and incubation conditions to favor a particular metabolic group of organisms

Question 25

bacterial membrane

Answer 25

phospholipid bilayer, hydrophobic(inside the membrane)/ hydrophillic,

Question 26

cytoplasmic membrane

Answer 26

also contains proteins embedded in the membrane, stabilized by hydrogen bonds and hydrophobic interactions

Question 27

what do membranes do?

Answer 27

They act as selective barriers allowing only small slightly charged molecules to pass, H20, H2S, N2,

Question 28

How do larger molecules get across the membrane?

Answer 28

they are transported across through proteins in the phospholipid bilayer

Question 29

What are the two main types of membrane proteins?

Answer 29

integral and peripheral

Question 30

What are the three types of energy sources for transport across the membrane?

Answer 30

The proton motive force (simple transport) PEP(phosphoenolpyruvate) for group translocation ATP for abc binding

Question 31

how is simple transport driven?

Answer 31

Its driven by the energy in the proton motive force

Question 32

How is group translocation?

Answer 32

chemical modification of the substance being transported driven by phosphoenolpyruvate

Question 33

how does the ABC transporter fueled?

Answer 33

Periplasmic binding proteins are involved and energy comes from ATP

Question 34

Uniporters

Answer 34

moves one substance across the membrane in one direction

Question 35

symporters

Answer 35

moves 2 substances at the same time in the same direction across the membrane, the first is usually the desired substance the second is usually needed to move the first across the membrane and it usually takes the 2nds concentration gradient into consideration

Question 36

Antiporters

Answer 36

1 substance goes across the membrane in one direction and the other is taken out, in the other direction.

Question 37

Simple transport

Answer 37

requires 1 membrane spanning protein and made of 12 alpha helices, and energy from a gradient goes across the membrane.

Question 38

what are some examples of simple transport/?

Answer 38

``` LAC PERMEASE, ( symporter) sulfate(symporter) potassium (uniporter) phosphate (symporter) sodium-proton (antiporter) ```

Question 39

group translocation

Answer 39

the substance is chemically modified and requires a set of proteins to transport the substance common type of group translocation is the phosphotransferase system with PO4- from PEP transferred to the substance transporter

Question 40

explain phosphotransferase system

Answer 40

its used to transport glucose, fructose and mannose, they are chemically modified during transport by phosphorylation and requires a set of five proteins for transport PO4 is passed along to each protein (phosphate cascade) and final transfer is to the sugar.

Question 41

which are nonspecific proteins in group translocation?

Answer 41

Enz 1 and HPR

Question 42

Which are specific proteins in group translocation?

Answer 42

Enz 2a, 2b, 2c

Question 43

why does this work for glucose/

Answer 43

its metabolically efficient because the phosphorylated glucose is the first step in glucose metabolism

Question 44

what is the conformational change that causes the glucose to move across the membrane

Answer 44

when PO4- is transferred to Enz2c, the energy causes the conformational change that moves glucose across the membrane and phosphorylation that creates the G6P

Question 45

The ABC binding system

Answer 45

requires a substrate binding protein, an membrane transport protein, an ATP hydrolyzing protein and ATP

Question 46

what does the abc system transport:?

Answer 46

sugars, amino acids, inorganic nutrients, trace minerals, and they have high substrate specificity

Question 47

What is the first step in ABC?

Answer 47

the substrate is first bound by a periplasmic binding protein (gram neg. bac.) or by an outer cytoplasmic membrane protein (gram pos) binding proteins are specific for each substrate

Question 48

What happens after the substrate is bound?

Answer 48

it is then transferred to a membrane spanning protein

Question 49

How is it moved across the membrane?

Answer 49

energy in ATP is used to to move the substrate across the membrane unmodified and into the cytoplasm (there is no PO4- transfer)

Question 50

Cell walls

Answer 50

located outside the cytoplasm, and functions to give rigidity to the cell, counteracts osmotic effects due to high solute concentrations in the cell,

Question 51

all cell walls of bacteria are divided into ?

Answer 51

gram negative and gram positive, difference due to peptidogylcan amounts

Question 52

bacterial cell wall rigidity is due to?

Answer 52

peptidoglycan

Question 53

Gram negative

Answer 53

mutlilayered, thin peptidoglycan outside the cytoplasmic membrane , there is a periplasmic space layer has a second layer, lps lipopolysaccharide

Question 54

gram positive

Answer 54

simple and thick, outside of cell membrane is thick layer of peptidoglycan

Question 55

gram +

Answer 55

90% of wall is peptidoglycan and have teichoic acids and different crosslinkages

Question 56

gram -

Answer 56

only 5-20% is peptidoglycan, and has periplasm and LPS

Question 57

Gram - lipopolysaccharide

Answer 57

is more permeable than the Cytoplasmic membrane, and has porins, lps spanning proteins with channels in the center that allow low MW molecules to pass through

Question 58

LPS is made of ?

Answer 58

2 polysaccharides, the O-polysaccharides, and core polysaccharidesand also fatty acids, with a lipid A with a glucosamine phosphate head and there are usually proteins that anchor the LPS to the membrane

Question 59

Periplasmic space of gram negative bacteria

Answer 59

contains three enzymes hydrolytic, binding proteins, chemoreceptors protons of the pmf are concentrated here

Question 60

cell surface functional structure

Answer 60

slime layer or capsule made of polysaccharides | for attachment to surface, or hosts, and for protection against host immune response

Question 61

cell pili and fimbriae

Answer 61

are made of protein extend from cell surface function to attach, for gene exchange(conjugation) motility receptors for viruses