Micro Exam 2

optimum growth pH

most favorable pH for the growth of an organism

minimum/maximum groth pH

Neutrophile

grow optimally at a pH within one or two pH units of the neutral pH of 7

Acidophile

grow optimally at pH of less that 5.5

Alkaphile

grow best at pH between 8.0 and 10.5

thermophiles

organisms that thrive at high temperatures, typically between 45°C and 80°C.

hyperthermophiles

extreme heat-loving microorganisms that thrive at temperatures above 80°C, often found in hot springs and deep-sea hydrothermal vents.

psychrophiles

organisms that thrive in cold temperatures, typically below 15°C. Can grow under 0°C, does not survive above 20°C

mesophiles

organisms that thrive at moderate temperatures, typically between 20°C and 45°C.

chemotrophs

obtain energy for electron transfer by breaking chemical bonds

phototrophs

obtain energy for electron transfer from light

heterotrophs

rely on more complex organic carbon compounds as nutrients

autotrophs

convert inorganic carbon dioxide into organic carbon compounds

metabolism

term used to describe all the chemical reactions inside a cell

endergonic reactions

require energy to proceed

exergonic reactions

spontaneous and release energy

anabolism

refers to those endergonic metabolic pathways involved in biosynthesis

catabolism

refers to exergonic pathways that break down complex molecules into simpler ones

ATP

main energy currency of the cell, stores and releases energy through the hydrolysis of its phosphate bonds

NADH

electron carrier that stores high energy electrons and donates them to the electron transport chain for ATP production

FADH2

electron carrier like NADH but donates the electrons later in the ETC

oxidation reactions

remove electrons from donor molecules

reduction reactions

add electrons to acceptor molecules

glycolosis

the metabolic pathway that converts glucose into pyruvate, producing ATP and NADH in the process. 

2 ATP 2 NADH 2 pyruvate

glycolosis net gain from one molecule of glucose ___ ATP, ___ NADH, ___ pyrucate,

enzyme

proteins that act as catalysts to help speed up a chemical reaction by lowering the activation energy

glycolysis, krebs cyccle, ETC

3 main pathways for producing energy

tricarboxylic acid cycle

another term for krebs cycle

oxidative phosphorylation

another term for ETC

glycolysis

most common pathway for the catabolism of glucose

does not require oxygen

cytoplasm

glycolysis takes place where in both prokaryotic and eukaryotic cells

mitochondria matrix

the transition reaction of glycolysis occurs in the ____ of eukaryotes

cytoplasm

the transition reaction of glycolysis occurs in the ____ of prokaryotes

krebs cycle

transfers remaining elextrons from the acetyl group produced during the transition reaction to electron carrier molecules, thus reducing them

cytoplasm

where does the krebs cycle occur in prokaryotes

krebs cycle

is a closed loop because the last part of the pathway regenerates the compound used in the first step

electron transport chain

the final step of cellular respiration, moves electrons from donors like NADH and FADH2 through electron carriers

negative to positive

in the electron transport chain, electrons flow from _______________ carriers, driving protons across the membrane, creating an energy difference

oxygen

final electron acceptor in aerobic respiration

cytochrome oxidase

final electron transport system carrier

aerobic respiration

what is not possible under these circumstances

no enzymes to neutralize harmful oxygen radicals

insufficient oxygen for aerobic respiration

no gene for appropriate cytochrome oxidase

inorganic molecules

final electron receptor in anaerobic respiration

fermentation

without respiration, NADH must turn back into NAD+ for glycolosis to continue, this is called_______

organic molecule

final electron acceptor in fermentation

2 ATP

fermenters can make a max of ______ from one glucose

glycolysis

only process involved in fermentation

glycolysis, Krebs cycle, ETC

3 processes involved in both anaerobic and aerobic respiration

substrates

enzymes bind to ____

active site

location where substrate binds to the enzyme

induced fit

enzyme structure changes slightly upon substrate binding

thymine

adenine binds to ___ in DNA

guanine

cytosine binds to ____ in DNA

replication

process of copying an organisms DNA to produce an identical duplicate

transcription

process of reading DNA to create RNA, particularly mRNA which carrier the genetic code to ribosomes

translation

process where ribosomes use mRNA to synthesize proteins based on the genetic information encoded in the mRNA

3000

the average bacteria has a genome of _____ genes in a single double stranded DNA

gene expression

transcription and translation are known as _____ involving the flow of gegenetic information from DNA to RNA to protein

DNA→transcription→RNA→translation→protein

initiation elongation termination

3 steps of DNA replication

plasmid

bacteria also have circular self replicating and nonchromosomal DNA called_____

exposure adhesion invasion infection

4 stages of pathogenesis

helicase

during DNA replication, DNA is unwound using

opens the DNA helix by breaking hydrogen bonds between the nitrogenous bases

DNA polymerase III

main enzyme that adds nucleotides into the 5’ and 3’ direction

ligase

seals the gaps between the okazaki fragments on the lagging strand to create one continuous DNA strand

primase

synthesizes RNA primers needed to start replication

single stranded binding protein

bind to single stranded DNA to prevent hydrogen bonding between DNA strands, reforming double stranded DNA

toposoimerase

relaxes rupercoiled chromosome to make DNA more accesible for replication, helps relieve stress on DNA when unwinding by causing breaks and then resealing the DNA

disease

any condition where the normal structure or functions of the body are damaged or impaired

infection

the successful colonization of a host by a microorganism

conjugation, transduction, transformation

Transfer of genetic material between different bacterial species is done through

sign

objective and measurable. can be directly observed by a clinician (body temp, HR)

transduction

Which of the following genetic transfer methods involves the release of a phage from the donor cell to the recipient cell?

nosocomial

diseases that are acquired in hospital settings

symptom

subjective, felt or experienced by the patient (loss of appetite, nausea)

intoxication

occurs through ingestion of toxins or poisons produced by microorganisms or their metabolic byproducts.

infectious

any disease caused by the direct effect of a pathogen

communicable

capable of being spread from person to person through either direct or indirect contact

zoonotic

diseases transmitted by an animal

acute disease

pathologic changes occur over a reltively short time and involve a rapid onset of sisease conditions (influenza incubation period is around 1-2 days)

chronic disease

pathogenic changes can occur over longer time spans (Hep B can occur for 6 months or more)

latent disease

casual pathogen goes dormant for extended periods of time with no active replication (chickenpox)

pathogenicity

ability of a microbial agent to cause disease

virulence

degree to which an organism is pathogenic

median infectious dose

number of pathogen cells or virions required to cause active infection in 50% of inoculated animals

median lethal dose

number of pathogenic cells, virions, or amount of toxins required to kill 50% of infected animals

adhesions

surface proteins or structures facilitating adhesion to host cells or tissues

pili and fimbriae

hair like appendages aiding in attachment to surfaces

pathogens

producte enzymes to promote invasion by breaking down host barriers

proteases lipases collagenases

secretion systems

specialized systems injecting proteins into host cells, manipulating cell functions for invasion

exotoxins

secreted toxins causing damage to host cells or tissues, including cytotoxins, neurotoxins, and enterotoxins

endotoxins

components of the bacterial cell wall, like lipopolysaccharides (LPS) triggering host inflammatory responses

capsules

polysaccharide coatings hindering phagocytosis by host immune cells

antigenic variation

changing surface antigens to evade host immune recognition

siderophores

molecules scavenging iron from the host, essential for bacterial growth

break down host tissues

what do collagenases, hyaluronidases, and proteases do by stimulatingan inflammatory response

quorum sensing

some bacteria use ____ to coordinate gene expression and virulence factor prodution in response to population density

pyrogenic

a substance that induces fever in the host, usually produced by bacteria or their toxins, also causes pus

staphylococci

facultative anaerobes

catalase positive

staphylococcus aureus

coagulase positive

can cause pneumonia, comiting, nausea, diarrhea,  abdominal pain

has been linked to toxic shock syndrome

can cause abscess formation

bacillus

genus of gram positive bacteria that are present in soil, water, and airborne dust

produces endospores

nonmotile, highly pathogenic

target modification

mutations that alter bacterial targets of the antibiotic (such as bacterial ribosomes) to reduce the binding affinity

enzyme degradation

inactivation of antibiotics through bacterial enzymes that chemically modify or destroy the drug