Microbio Exam 1

What is microbiology?

the study of organisms too small to be seen without magnification

What are the 7 microorganisms/microbes we study?

1. bacteria

2. viruses

3. Fungi

4. Prions

5. Helminths (worms)

6. Protozoa

7. Algae

Medical Microbiology

studies the effects of microorganisms on human beings

Public Health Microbiology and Epidemiology

monitor and control the spread of diseases in communities

Immunology

study of the body's resistance to infectious disease

Industrial Microbiology

branch of microbiology in which microbes are manipulated to manufacture useful products

Agricultural Microbiology

relationships between microbes and domesticated plants and animals

Environmental Microbiology

branch of microbiology studying the role of microorganisms in soils, water, and other habitats

When did microbes first appear?

Prokaryotes: 3.5 billion years ago

Eukaryotes: 1.8-2 billion years ago

Prokaryotes

- No nucleus or membrane bound organelles

- evolved first

- smaller and simpler

- unicellular

- archaea & bacteria

- one chromosome (small circular DNA)

Eukaryotes

- Nucleus and organelles present

- evolved later

- bigger and more complex

- unicellular & multicellular

- fungi, plants, animals, protists

- multiple linear chromosomes

Both

- cell membrane

- cytoplasm

- DNA

- ribosomes

Evolution

Change in a kind of organism over time; process by which modern organisms have descended from ancient organisms.

Contribution of photosynthetic and decomposition microbes

Photosynthetic: light fueled conversion of CO2 to organic material

Decomposition: breakdown dead matter and wastes into simple compounds

Biotechnology

The manipulation of living organisms or their components to produce useful products.

Bioremediation

Use of living organisms such as prokaryotes, fungi, or plants to detoxify polluted ecosystems.

Recombinant DNA technology

technology that allows for manipulation of genetic material

Pathogen

A disease-causing microbe

Communicable (infectious)

can be spread from one host to another

Noncommunicable (noninfectious)

those illnesses that cannot be transmitted from one person to another

U.S. diseases vs other countries

the U.S. sees higher rates of chronic, noncommunicable diseases whereas other countries see more communicable diseases.

What other noninfectious diseases do microbes cause?

- cancer

- atherosclerosis (heart disease)

- type 2 diabetes & metabolic syndrome

- chronic respiratory diseases

- autoimmune diseases

Who developed the first microscopes?

Hooke and Van Leeuwenhoek

Louis Pasteur

disproved spontaneous generation with swan-neck flasks and broth. This experiment also proved the theory of biogenesis

In 1864 he proved that exposing wine and milk to heat for a few minutes, disease causing pathogens would die without causing harm to the beverages, meaning they could be stored longer (pasteurization)

Edward Jenner

Developed a vaccine for smallpox in 1796 using pus from milkmaids that had cowpox blisters on their hands

John Tyndall

showed evidence that some microbes have very high heat resistance and are difficult to destroy

Ferdinand Cohn

discovered and described heat-resistant endospores

Aseptic Technique

precautions taken to prevent contamination of a surgical wound

Dr. Oliver Wendell Holmes

observed that mothers of home births had fewer infections than those who gave birth in hospitals

Dr. Ignaz Semmelweis

correlated infections with physicians coming directly from the autopsy room to the maternity ward

Joseph Lister

discovered how antiseptics prevented infection

Robert Koch

proved germ theory of disease using postulates

Germ Theory of Disease

idea that infectious diseases are caused by microorganisms

Carl von Linne

began systematically classifying living things

binomial nomenclature

genus + species

(ex: Staphylococcus aureus)

Levels of classification (largest to smallest)

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Phylogeny

natural relatedness between groups of organisms

Systems for presenting a universal tree of life

• 3 domain system: bacteria, archaea, eukarya

• 2 domain systems: prokarya, eukarya

Matter

anything that takes up space and has mass

Atom

Basic unit of matter

Element

A pure substance made of only one kind of atom

Isotope

Atoms of the same element that have different numbers of neutrons

radioactive isotope

an isotope that has an unstable nucleus that decays over time and that emits radiation

CHONPS

the 6 most important elements that form the foundation for all living things: carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur

Energy Levels

the possible energies that electrons in an atom can have

Orbitals

regions around the nucleus in which given electron or electron pair is likely to be found

valence electrons

Electrons in the outermost shell of an atom that determine the degree of reactivity & types of bonds an element can make

ionic bond

Formed when one or more electrons are transferred from one atom to another

Cations

positively charged ions

Anions

negatively charged ions

covalent bond

A chemical bond that involves sharing a pair of electrons between atoms in a molecule

polar covalent bond

A covalent bond in which electrons are not shared equally

nonpolar covalent bond

A type of covalent bond in which electrons are shared equally between two atoms of similar electronegativity.

hydrogen bond

Attraction between a slightly positive hydrogen atom and a slightly negative atom.

Why are hydrogen bonds important?

hydrogen bonds stabilize the structure of water, DNA, and protein

molecular formula

A chemical formula that shows the number and kinds of atoms in a molecule, but not the arrangement of the atoms.

structural formula

a formula that shows the arrangement of atoms in the molecule of a compound.

What is the correct way to write a chemical reaction?

reactants (left) -> products (right)

catalysts

any substance (organic or inorganic) that speeds up chemical reactions

Enzymes

specifically PROTEINS that act as biological catalysts

What is a solution?

a mixture of solute and solvent

Equation for concentration

C = m/v

m = moles of solute

v = volume of solution (L)

Hydrophobic

water repelling

Hydrophillic

Attracted to water

amphipathic

having both a hydrophilic region and a hydrophobic region

acid

solution that produces H+

Base

A substance that decreases the H+ concentration in a solution.

pH scale

1-7 is acidic (higher H+ than hydroxide)

7-14 is basic (higher hydroxide than H+)

7 is neutral (equal H+ and hydroxide)

How is pH mathematically expressed?

pH = -log [H+]

How many more (or less) H+ does 1 point change on the pH scale?

10x more or less

Organic chemistry

the study of carbon compounds

Organic Molecules

molecules that contain carbon, hydrogen, and oxygen

Why is carbon important?

carbon has the ability to form 4 covalent bonds with other atoms, making it ideal for building complex molecules

hydroxyl group

A functional group consisting of a hydrogen atom joined to an oxygen atom by a polar covalent bond. Molecules possessing this group are soluble in water and are called alcohols.

carbonyl group

A chemical group present in aldehydes and ketones and consisting of a carbon atom double-bonded to an oxygen atom.

carboxyl group

A functional group present in organic acids and consisting of a single carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group.

amino group

a chemical group consisting of a nitrogen atom bonded to two hydrogen atoms

phosphate group

A functional group consisting of a phosphorus atom covalently bonded to four oxygen atoms

sulfhydryl group

A functional group consisting of a sulfur atom bonded to a hydrogen atom (—SH).

What do carbon functional groups give to larger molecules?

- reactivity and bonding

- polarity and solubility

- energy storage and transfer

- biological function

aldehyde vs ketone

Aldehydes have a terminal carbonyl group (R‑CHO) bonded to at least one hydrogen, while ketones have an internal carbonyl group (R‑CO‑R') bonded to two carbon atoms; this structural difference makes aldehydes more reactive and more easily oxidized than ketones.

Proteins

Nutrients made of amino acids that the body uses to build and maintain its cells and tissues

Carbohydrates

made of simple sugars. Broken down to glucose to provide energy.

Nucleic Acids

Made of nucleotides, function is to store genetic information which can be seen in DNA and RNA

Lipids

Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen.

dehydration synthesis

A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.

Hydrolysis

A chemical process that splits a molecule by adding water.

Monosaccharides

simple sugars

Disaccharides

Carbohydrates that are made up of two monosaccharides

Polysaccharides

Carbohydrates that are made up of more than two monosaccharides

Cellulose

polysaccharide consisting of glucose monomers that reinforces plant-cell walls

Agar

a gel-like polysaccharide compound used for culturing microbes; extracted from certain red algae

Chitin

A structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeletons of all arthropods.

Peptidoglycan

A protein-carbohydrate compound that makes the cell walls of bacteria rigid

glycocalyx capsule

a bacterial capsule that is made of a fuzzy coat of sticky sugars

Starch

A storage polysaccharide in plants consisting entirely of glucose.

Glycogen

storage form of glucose in animals

Triglycerides

an energy-rich compound made up of a single molecule of glycerol and three molecules of fatty acid.

Saturated fatty acids

Fatty acids with no double bonds.

Unsaturated Fatty Acids

Fatty acids with one or more double bonds.