microbio exam 1

vals

microorganisms will only refer to these 5.

Bacteria, archaea, fungi, protozoa, algae, and viruses

Cellular composition

all life is composed of cells

cells are the most basic functional and structural unit of life; cells perform all functions for life

metabolism

The sum total of all chemical reactions occurring in a cell.

homeostasis

the regulation of internal environment despite changes in the external & internal environment. (heat shock proteins)

Growth and development

consistently grow and develope based on inherited genes

Reproduction

ability to make more offspring like them, and pass down genetic info.

Response to stimuli

the ability to respond to external stimuli; usually produces movement

Evolutionary adaptation

the change in genetic info in a population over time (evolution)

Macromolecules make up cells:

• Proteins

• Lipids

• Carbohydrates

• Nucleic Acids

proteins can serve as ____ for biochemical reactions.

Enzymes

any polymerase =

synthesizes new strands of nucleic acids

flagellin -

subunit of flagellum

Actin/myosin -

components of the cytoskeleton

amino acids are ______ of proteins

monomers

lipids

large, nonpolar, non-soluble molecules

- structural -> plasma membrane

- long-term energy storage -> macro organisms

- cell communication and regulation (steroids/hormones)

____________ serve as energy storage and structural components of cells.

Carbohydrates

carbohydrates are polymers of ______

monosaccharides

_____ → cell wall of fungi

chitin

Starch → plants

True

glycogen → animals (many glucose (monosaccharide))

True

_________ store genetic information (DNA) and facilitate protein synthesis (RNA).

Nucleic Acids

in 1970

Carl Woese sequenced and compared 16svRNA gene of many organisms

bacteria are similar to Archaea due to _______

prokaryotic characteristics

archaea is similar to ______ due to ______

Eukaryotes; histore-live proteins

viruses are NOT _____

cellular

viruses require a ____ for replication

host

viruses CANT _____

metabolize

viruses are _____ outside of a host cell

inactive

Why study microbes?

Fast & cheap

Produce enzymes & molecules for industrial/medical uses.

Genetic manipulation is much easier.

How did the first microbial life arise?

Primordial soup → contained all required atoms for life.

organic molecules could form in early Earths history

organic molecules have high affinity for _________

Iron pyrite

Ribozymes

RNA molecules with catalytic functions

Micelle

single lipid layer

When and how did eukaryotes appear?

Endosymbiotic theory

How do microbes obtain energy?

• Heterotroph

• Autotroph

_______ → 2 ATP; no oxygen

Fermentation

________→ up to 36 ATP

Aerobic respiration

Bacteria use ______ DNA for storage of genetic information.

double-stranded

DNA lacks the _________

free 2’ hydroxyl. 

______ - extra chromosomal DNA

plasmids

Anton van Leeuwenhoek

1600s - discovered microorganisms

Louis Pasteur

1800s - experiment disproved spontaneous generation theory.

Robert Koch

1800s - Koch’s Postulates & discovered cause of anthrax

prototrophs

can synthesize all macromolecules from a single carbon source and inorganic molecules

• Escherichia coli

Auxotrophs

must acquire macromolecules

• Bacteroides valgatus → must acquire arginine

Aerobes

grows with oxygen

anaerobes

grows without oxygen

Obligate anaerobes

grows in anoxic environments ( ABSOLUTELY NO OXYGEN)

• Clostridium spp

Facultative (an)aerobes

Can grow in the presence or absence of oxygen

• E. Coli

Aerotolerant

can grow with oxygen but do not use it

O2 can produce ______ that attack macromolecules

oxidants

Obligate aerobes

Grows best at atmospheric O2 levels

• pseudomonas spp

Microaerophiles

Grows best at very low levels of oxygen

• helicobacter pyloric

Acidophiles →

< 5.5 ph 

lactobacillus

Neutrophiles

5.6 - 8.5 pH

E. coli

Alkaliphiles

8.6>pH

Cyanobacteria (some)

Effects of pH on microbial growth:

affects transmembrane activity;

signal transduction;

gene expression;

ATP synthase

Most ______ need a_{w (water activity) ______} 0.9

bacteria; less than

Higher temperatures raise thermal energy availability in molecules →

Makes them more reactive

hyperthermophiles

→ 85 C; pyrococcus furiosus

thermophiles

→ 55-85 C; thermococcus literalis

mesophiles

→ 10 - 54 C; staphylococcus areus

psychrophiles

→ 10 lower psychromonas

Growth media

A mixture/combo of organic and inorganic nutrients

• Liquid (broths)

• Solid (agar plates)

• Complex

• Defined

Specialized media

• Selective

• Differential

• Enriched