Microbial%20GrowthSV - Microbial Growth Microbial Growth...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Microbial Growth ± Microbial growth is the increase in number of cells, not cell size The Requirements for Growth: Physical Requirements ± Temperature ± ± Optimum growth temperature ± Temperature Category ± Psychrophiles ± like it cold, just below freezing, up to ~20 °C ± Psychrotrophs ± Grow between 0°C-20 and up to 30°C ± ± ± Cause food spoilage ± Mesophiles ± prefer moderately warm temps, ~20°C - 45°C ± Thermophiles ± Psychrotrophs ± Grow between 0°C and 20-30°C ± pH ± Most bacteria grow between pH 6.5 and 7.5 ± Molds and yeasts grow between pH 5 and 6 ± ± Osmotic Pressure ± Hypertonic environments, increase salt or sugar, cause plasmolysis ± Extreme or obligate halophiles require high osmotic pressure ± Facultative halophiles tolerate high osmotic pressure ± Halophiles - salt loving ± salt conc. in body ± salt conc. in ocean ± salt conc. in Dead Sea and Great Salt Lake The Requirements for Growth: Chemical Requirements ± Carbon ± Structural organic molecules, energy source ± Chemoheterotrophs use organic carbon sources ± ± N, S, P ± Trace elements ± Inorganic elements required in small amounts ± Toxic Forms of Oxygen ± Singlet oxygen: O 2 boosted to a higher-energy state
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

Microbial%20GrowthSV - Microbial Growth Microbial Growth...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online