intro to microbiology final cumulative portion

microbiology

the study of organisms that are invisible to the naked eye

ubiquity of microbes

the property of being found everywhere

are all microbes bad?

some microbes cause disease, but most are essential for life

six types of microbes

bacteria, fungi, algae, protozoa, helminths, viruses

viruses

not included in the tree of life, considered non living particles because they require host cell DNA to replicate

who disproved spontaneous generation and how?

Louis Pasteur with the swan neck experiment

taxonomy

a method of naming living things

What is included in domain Eukarya?

algae, fungi, protozoa, helminths

What are the three domains of life?

Eukarya, Archaea, Bacteria

Types of fungi

yeast, mold, dimorphic

Conidiospore

free asexual mold spores

Sporangiospores

asexual mold spores enclosed in a sac

Red tides

increase in growth of dinoflagellates, toxic to humans and animals

Trophozoite

active stage of protozoa

Cyst

dormant, protective stage of protozoa for harsh environments

Why are helminths considered microorganisms?

because their eggs cannot be observed with the naked eye

What are lichens?

symbiotic relationship between a fungus and photosynthetic partner

isomer

a compound with the same formula but a different structure

3 principles of modern cell theory

all organisms are composed of cells, cells can only arise from other cells, cells are fundamental units of structure and function in organisms

endosymbiotic theory

mitochondria and chloroplasts were once independent bacterial cells that got engulfed into larger cells

support for endosymbiotic theory

chloroplasts and mitochondria have their own DNA, ribosomes, and divide via binary fission

Pleomorphism

when a bacteria can change shape based on environmental conditions

Monotrichous

one flagellum

lophotrichous

multiple flagella at one pole

amphitrichous

flagella at both poles

peritrichous

flagella all over the cell

runs

straight-line movement of bacteria

tumbles

rotation of bacteria for movement

taxis

movement towards or away from a stimulus

chemotaxis

movement in response to chemicals

phototaxis

movement in response to light

gram positive bacteria

have a thick peptidoglycan layer and one cell membrane

gram negative bacteria

have a thin peptidoglycan layer and two cell membranes

Endospores

antibiotic resistant forms that bacteria can become when under stress

endocytosis

taking in substances through engulfing

phagocytosis

engulfing large particles

pinocytosis

engulfing small liquid or particles

receptor-mediated endocytosis

ligand binding causes vesicles to form and take in the particles

rough ER function

protein synthesis, site of ribosomes

smooth ER function

lipid synthesis

enveloped virus

nucleic acid, capsid, and lipid bilayer

non-enveloped or naked virus

nucleic acid and capsid only

viral spikes

glycoproteins used for attachment to host cells

6 ways viruses are classified

disease it causes, host it infects, tissues it infects, genetic material, chemical composition, physical structure

life cycle of an animal virus

attachment, entry, uncoating, biosynthesis, assembly, release

how are plant viruses different from animal viruses?

plant cell wall means they have to enter through open wounds or insect vectors and leave through the plant’s transport systems

bacteriophage life cycles

lytic cylce, which looks like a regular virus cycle, lysogenic cycle where viral DNA integrates itself into the host genome and enters the lytic cycle under stress

viroid

plant pathogens composed of short, circular DNA

prions

infectious misfolded proteins that can spread to other proteins, have no nucleic acids, so cannot be destroyed by UV or nucleases, and can be transmitted between humans and animals

how to enzymes work?

speed up reactions by lowering activation energy

EMP glycolysis pathway

net gain of 2 ATP, 2NADH, 2 pyruvate

pentose phosphate pathway for glycolysis

important for macromolecule production

ED pathway for glycolysis

only possessed by certain bacteria, independent of other pathways, uses ethanol for a net gain of 1 ATP

transition reaction

removal of a carboxyl group from pyruvate and attachment of the remaining molecule to Coenzyme A to make acetyl-CoA and 1 NADH

how many ATPs does aerobic respiration yield?

38 ATPs

how many ATPs does anaerobic respiration use and what type of molecules are final the electron acceptor

inorganic molecules, 5-36 ATPs

how many ATPs does fermentation yield and what is its final electron acceptor

organic molecules, yields 2 ATPs

Lipases

catalyze the break down of triglycerides

phospholipases

catalyze the breakdown of phospholipids

Beta-oxidiation

in krebs cycle, fatty acids have to remove acetyl groups to be catabolized

bacteria replication

binary fission

obligate aerobes

require oxygen to survive

facultative anaerobes

can utilize oxygen and can grow without ito

obligate anaerobes

cannot grown in the presence of oxygen

aerotolerant anaerobes

cannot use oxygen, but can survive with it

microaerophiles

can only grow in low oxygen conditions

capnophiles

requires high CO2 levels to grow

growth factors

organic factors that must be provided to a microbe as a nutrient

fastidious microbes

require multiple growth factors

quorum sensing

signaling between cells in a biofilm to coordinate activities in response to changing environments

topoisomerase and DNA gyrase

relax supercoiled DNA

Helicase

unwinds DNA

DNA polymerase III

synthesizes new DNA strands

Okazaki fragments

the fragments of the lagging strand, composed of fragments of RNA & DNA with gaps in between.

DNA polymerase I

removes RNA primers and replaces them with DNA

DNA ligase

seals gaps in newly synthesized DNA

DNA polymerase delta

lagging strand replication in eukaryotes

DNA polymerase epsilon

leading strand replication in eukaryotes

RNAse H

removes RNA primer in eukaryotes

telomerase

adds nucleotides to the 3’ telomere noncoding end

PCNA proliferating cell nuclear antigen

sliding clamp for polymerase stabilization in eukaryotes

telomere function

prevent loss of DNA during replication

central dogma

DNA is transcribed to RNA then translated into proteins

mRNA

carries genetic code

rRNA

forms ribosomes

tRNA

carries amino acids

3 mRNA processing things

5’ cap, poly-A tail, splice out introns

plasmid replication

rolling circle replication or unidirectional replication

post translational modifications

protein folding, cleavage, chemical modifications

housekeeping genes

essential genes that are always expressed

constitutive genes

genes that are always on to constantly make proteins

regulated genes

genes that be induced or repressed based on what the cell needs

operon

a cluster of genes controlled by a single promoter and operator

promoter

where RNA polymerase binds to begin transcription

operator

traffic light that turns transcription on and off

regulatory gene

encodes a repressor protein that controls the operator

trp operon

when tryptophan is present, it binds to the repressor and causes transcription to be blocked: repression

lac operon

when lactose is present, it binds to the repressor and makes it stop blocking transcription: induction

DNA repair mechanisms

proofreading via DNA polymerase, mismatch repair, excision repair, photoreactivation

conjugation

direct horizontal gene transfer via sex pilus