Intro to Microbiology (Chapter 1), The Cell (Chapter 3), & Microbial Growth (Chapter 9) 🧑‍🔬

Antony van Leeuwenhoek:

first person to publish microorganism exist

microorganism= tiny living things

Robert Hooke

invented the first microscope

Francesco Redi

first person to oppose spontaneous generation 

Louis Pasteur

disapproved of spontaneous generation wrong & approve biogenesis

Ferdinand Cohn

discovered endospores

Spontaneous generation

explanation of tiny living things exist/ living things arise from NON living things is proven wrong

Biogenesis

life creates life approved by Louis Pasteur

microbiota/microflora

the good bacteria in the body

Pathogens

disease

Emerging infectious disease (EID)

common bacteria within last 35 years

Acellular infectious agents and the “agents” that this refers to

(viruses, prions ect…):

Endospores

 heat resistant bacteria

Be able to recognize a scientific name written in the CORRECT scientific format 

• Escherichia coli 

• Staphylococcus aureus

• Can be underline/italicized & genus is capitalized only

Prokaryotic

No nucleus & no mem bound organelles but do have organelle 

(nucleoid region- DNA floating)

Prokaryotic

Cytoplasmic mem 

(phospholipid bilayer)

prokaryotic

Cell wall of peptidoglycan in bacteria and polysaccharide in archaea

Prokaryotic

70 ribosomes

Prokaryotic

Bacteria (single cell organism)

Archaea (extremophiles & single cell)

Eukaryotic

True mem bound nucleus & organelles

Eukaryotic

Fungus (fungi)

Protozoans (animal like)

Animals (helminth)

Algae

Plants

Eukaryotic

Plasma mem  (phospholipid bilayer)

Some have cell walls & some don’t

Eukaryotic

80 ribosomes

Acellular Infectious Agent

• viruses, viroid’s, prions →NOT LIVING, NO ORGANISM, NO CELL, NO PRO/EUKARYOTIC 

Be able to differentiate between microorganisms and microbes especially why microbiologist had to create the term “microbes” when “microorganism” already existed

• Microorganism: (small living things) bacteria, protozoans, archaea, algae, helminth, fungi 

• Microbes: viruses, viroids, prions 

• Microbiologist created the term microbes to include acellular agents (viruses)

Know the common shapes of bacterial cells (morphology=shape) 

• Coccus: round 

• Bacillus: rod 

• Vibrio: v shape 

• Sprilium: spiral shape 

• Spirochete: long loose 

Know the common arrangements of bacterial cells (multiple cells “hand out”) 

• Single, diplo/pairs (divide, no separate), chains, clusters, tetrads (4 group), palisades (side/side) 

Know what structures make up the cell envelope of bacteria and their order from deep to superficial 

• Cytoplasmic membrane (phospholipid bilayer) 

• Cell wall (peptidoglycan) 

• Capsule (if present)

Know the structure and importance/function of the cytoplasmic membranes of all cells 

• Cytoplasmic mem is the innermost layer of envelope, boundary of cell & contains the cytoplasm 

• Prospholipid bilayer embedded w/proteins 

• Hydrophilic love water head out, hydrophobic hate water tail in 

• Fluid mosaic model: movement of proteins embedded allowing stuff to enter/out

Define diffusion & osmosis 

• Diffusion: movement from high to low concentration until equilibrium is reached & is why the cell mem works 

• Osmosis: diffusion of water from high to low concentration

Know the various ways substances travel through a cytoplasmic membrane to get in/out of a cell and when/why each method is used

• Simple diffusion: small hydrophobic molecules and water pass 

• Facilitate diffusion: other molecules move across membrane via transport system 

• Active transport: use ATP to force molecules to go from low to high concentration

• Each of the method i used by transport system that carrier certain molecule type by protein

+Know bacterial cell wall

• All bacteria have a cell wall distinguished into two type of bacteria ⬇

• G+: thick peptidoglycan for structure support and strength , teichoic acid & lipoteichoic acid for attachment to surface

• G-: thin peptidoglycan for same function,  outer membrane to keep antibiotic out & selectively permeable mem, o-polysaccharide for antigen (name tag), core polysaccharide for attaching to tissue and lipid A to build toxin 

If an environment is hypertonic or hypotonic, know what that means in terms of solute concentration, know in which direction water will move in regard to the cell in that environment AND what will happen to the cell when that occurs 

(image)

• Water follows solute 

• The bacteria will lysis or the bacteria will crenate and die

Know what NAG and NAM are 

• Both are proteins that make up peptidoglycan 

Know what biofilms are and their implication in disease/infections 

• Biofilms are the substance that creates … to protect ?

• Teichoic acid help gram stick including biofilm formation and host tissue adhesion

Know the functions of capsules and slime layer and what they are made of 

• Capsule and slime layer function as attachment that cause cause disease 

• They are made as glycocalyx and some polypeptides and can grow as biofilm

Know the functions of flagella, pili, fimbriae, and sex pilus 

• Flagella: linear motility movement , function in mortality 

• Pili: rotational movement 

• Fimbriae: attachment 

• Sex pilus: allow bacteria to exchange or transfer DNA

Taxis behavior & the specific definitions of chemotaxis, phototaxis, aerotaxis & magnetotaxis 

• Taxis: movement toward or away

• Chemotaxis: toward/away chemicals 

• Aerotaxis: toward/away oxygen 

• Thermotaxis: toward/away heat 

• Phototaxis: toward/away light 

• Magneototaxis: toward/away

Know where the chromosome is located in bacterial cells and be able to distinguish if from eukaryotic chromosomes 

• Nucleoid region is where the chromosome is located 

Know what a plasmid is, where it is located, and what kind of information it carries 

• Plasmids are extra codes of DNA (genes) that are located  outside the nucleoid 

Include toxins antibiotic resistance, capsule/slime layer and fimbriae

• It carriers chromosomes that has DNA to make protein for survival

Know the function of ribosomes 

• Protein synthesis, 70s 

+Know the bacterial internal component 

• Cytoplasm: inside cell 

• Cytoskeleton : cell structure and shape 

• Gas vehicle: float (buoyancy) 

• Storage  granule: store stuff

Know all about endospores, sporulation, and germination 

• Endospores dormant form of a bacteria cell

• Sporulation is production/creation/making of endospores 

• Germination is when the environment is favorable again and become bacterial cell again 

Know the function of the cytoskeleton in both prokaryotic cells and eukaryotic cells 

• Cytokeleton keep shape and structure of both cells

+Know what all have in common of eukaryotic cell 

• Mem bound nucleus

• Mem bound organelles 

• Cytoplasmic mem 

• 80 ribosomes

For eukaryotic cells, know the function of cilia, function of the organelles (nucleus, nucleolus, mitochondria, chloroplasts, smooth & rough endoplasmic reticuli, golgi, lysosomes, and peroxisomes 

• Cillia creates water currency around the cell

• Nucleus store DNA (genetic material) 

• Nucleolus is where ribosome are created (ribosome factory)

• Mitochondria generate ATP 

• SER function a lipid synthesis & lipid degrading 

• RER function as ribosome attach & site of protein synthesis & modification for protein 

• Golgi is the shipping and receiving center of the cell 

• Vesicle is the hollow  sac of membrane that carry tuff in/out of cell 

• Lysosome is the hollow sac of membrane that contains digestive enzyme 

• Peroxisome is the hollow sac of membrane that detoxify certain chemical

Define endocytosis and exocytosis

• Endocytosis: inside cell 

• Exocytosis: out cell 

Define phagocytosis and pinocytosis 

• Phagocytosis engulf large particle 

• Pinocytosis are cell taking in liquid

Know how binary fission differs from mitosis 

• Binary fission bacteria have no nucleus where mitosis have a nucleus 

Know what generation time is, how it can be affected, and why is it important to understand in terms of infections 

• Generation time is time it takes for the population to double 

• Undergo binary fission 

Know what an open system is in terms of nutrient replenishment and waste removal & be able to identify examples of an open system 

• Open system: replacing nutrient and dividing quickly (exponential growth) 

• For example: the human body, soil, bodies of water etc.

Define/explain quorum sensing 

• Quorum sensing is the ability for bacteria to sense their environment and send chemical signals to surrounding cells to collectively perform an action  

Know what biofilm is how they form and their medical significance 

• Biofilm is bacteria multiplying out of control that stick to a surface and produce a sticky matrix (EPS) that protects bacteria from the immune system. 

Know the steps of the closed system growth curve in order that they happen AND what is occurring in terms of bacteria growth/death, amount of nutrients available in the system, and amount of waste build up

• Lag phase: no growth, bacteria take in nutrient 

• Exponential phase: doubling population

• Stationary phase: death rate=birth rate 

• Death phase: bacteria starving to death & waste still there 

• Phase of prolonged decline: survivors and become cannibals

Define ubiquitous

• Found everywhere 

Know the 5 major factors that affect microbial growth and ultimately WHY/HOW they affect growth rates

• Temperature affect enzyme efficacy 

• pH affect enzyme efficacy 

• Atmosphere all metabolic needs to make ATP 

• Osmotic pressure 

• Nutrient availability

Differentiate among Psychrophile, Psychrotrophs, Mesophiles, Thermophiles, and Hyperthermophiles

• Psychrophilies: must be in a cold environment in order to survive 

• Psychrotrophs: don’t necessarily need to stay in a cold environment to survive but can want to

• Mesophiles: moderate temperature environment to survive + pathogen are classified 

• Thermophiles: live in heat resistant to survive 

• Hyperthermophiles: live in HOT temp to survive

Know which one most to all pathogens are classified as

Mesophiles

Differentiate among obligate aerobes, facultative anaerobes, obligate anaerobes, microaerophiles, and aerotollerant 

anaerobes and examples of where you might find some of them in or on the human body

• Obligate aerobes: must have oxygen to survive and grow  

• Facultative anaerobes: based on a need, can grow with or without oxygen but prefers oxygen (adapt

• Obligate anaerobes: must be without oxygen 

• Microaerophiles: grow oxygen but use CO2 more

• Aerotollerant anaerobes: no oxygen needed

Differentiate among neutrophiles, acidophiles, and alkaliphiles and identify examples of where you might find some of

them in or on the body

• Neutrophiles: neutral pH 

• Acidophiles: acidic pH (low)

• Akaliphiles: basic /alkaline pH (high)

Differentiate between halotolerant bacteria and halophiles

• Halotolerant: survive in small amount of salt 

• Halophiles: require salt environment to survive 

Know where you might find halotolerant bacteria in or on the human body

• Skin pore, sebum, saline 

Know the difference between major elements and trace elements

• Major elements: nutrient needed 

• Trace elements: nutrient needed in small amount 

Know what a growth factor is and why some organisms need them

• Organism cannot grow/synthesis itself 

• Organisms are fastidious because they require the nutrients ready and available they can’t build

Distinguish between heterotrophs and autotrophs

• Heterotrophs: eat/consume organic carbon “food” 

• Autotrophs: inorganic molecule CO2

Distinguish between phototrophs, chemoorganotrophs, and chemolithotrophs

• Phototrophs: energy from sunlight 

• Chemoorganotrophs: consume organic molecule 

• Chemolithotrophs: get energy from breaking inorganic chemicals