Assessment 2

Metabolism

All chemical reactions that occur to keep cells alive and functioning

Enzyme

Biological catalyst that facilitates chemical reactions within a cell

Ends in “-ase”

Enzyme function

Each enzyme can catalyze one specific reaction

But can do it over and over again

Factors that increase enzyme activity

-Warmer temperature (unless it gets too hot, then it will denature)

-Optimal pH

Factors that decrease enzyme activity

-Too hot or cold temperatures

-pH too acidic or basic

-Denaturing agents (high salt, heavy metals, some solvents)

-Enzyme inhibitors (drugs)

Glycolysis

Breaks down glucose to make ATP

What goes into glycolysis

Glucose

What comes out of glycolysis

-2 pyruvic acid

-2 ATP

-2 NADH

Kreb’s cycle 

Gets rid of pyruvic acid

What goes into the Krebs cycle

2 pyruvic acid

What comes out of the Krebs cycle

-2 ATP

-6 CO2

Electron transport chain (ETC)

Empty the buckets, regenerate NAD+ and FAD

What goes into ETC

-10 NADH (3 ATP)

-2 FADH2 (2 ATP)

-Final electron acceptor (O2)

What comes out of ETC

-10 NAD+

-2 FAD 

-34 ATP

-Waste product (H2O)

Fermentation

Deals with NADH and pyruvic acid from glycolysis

What goes into fermentation

-2 pyruvic acid

-2 NADH

What comes out of fermentation

-2 NADH+

-Various waste products

Glycolysis + respiration=

38 ATP

Glycolysis + fermentation=

2 ATP

Aerobic respiration

Uses O2 as the final electron acceptor, resulting in H2O as a waste product

Anaerobic respiration

Is cellular respiration, but uses electron acceptors other than O2, such as sulfate or carbonate

Obligate aerobes

Require O2 for survival and respiration 

Obligate anaerobes

-Killed by oxygen

-Can do anaerobic respiration or fermentation

Aerotolerant anaerobes

-Tolerate O2, do not use it but are not harmed

-Only do fermentation

Facultative anaerobes

-Can survive without O2, but prefer it

-Prefer respiration to produce more ATP, will survive by fermentation

Microaerophiles

-Use O2 in metabolism

-Cannot survive in atmospheric concentrations of O2

Microscopic morphology

-Appearance of individual cells under the microscope

-Cell shape (cocci/bacilli) and arrangement (strepto/staphylo)

Colony morphology

-Describes an individual spot of growth

-Color, shape, texture, opaque/ translucent, elevation

Biofilm

Complex community or ecosystem that includes multiple species of microbes

How does biofilms contribute to human disease

-Difficult to eliminate with antibiotics or disinfectants

-Can grow onto medical devices and get into bloodstream

Lag phase

Cells are actively metabolizing but are not dividing yet

Log phase

-Cells divide at maximum rate

-Population doubles with every generation

Stationary phase

Cells are dividing but also dying'

*Rate of cell division=rate of cell death

Death phase

Rate of cell death exceeds rate of cell division

*Population dies off

Archaea domain

-Single celled prokaryote

-Live in extreme environments

-Do not directly cause human disease

Bacteria domain

-Single celled prokaryotes

-Some cause human disease

Eukarya domain

-Single or multicellular eukaryotes

-Some cause human disease

Monera kingdom

-All prokaryotes

-Bacteria and archaea

Animalia kingdom

-Multicellular eukaryotes

-No cell walls

-Chemotrophs

Plantae kingdom

-Multicellular eukaryotes

-With cell walls

-Chloroplasts

-Phototrophs

Fungi kingdom

-Single or multicellular eukaryotes

-Chemotrophs

Protista kingdom

-Single celled eukaryotes

-Some phototrophs, some chemotrophs

Gram stain test

-Gram positive organisms stay a crystal violet color

-Gram negative organisms have no/thin cell wall that dissolves in ethanol, so it will be a red color from the safranin dye