Biology Ch. 5&6

Metabolism & Bacterial Growth and Culturing
the sum of all the chemical processes carried out by living organisms
requires energy to synthesize complex molecules from simpler ones
anabolism example
growth, reproduction, repair
releases energy by breaking down complex molecules into simpler ones
catabolism example
captures its own energy and uses carbon dioxide to synthesize organic molecules. makes its own food.
captures energy from sunlight and uses carbon dioxide to make carbohydrates(energy). photosynthesizes.
photoautotroph example
cyanobacteria, algae, plants
uses energy from inorganic substances such as sulfides or nitrates and uses carbon dioxide to make carbohydrates(energy). does not photosynthesize.
chemoautotroph example
nitrogen-fixing bacteria
uses ready made organic molecules obtained from other organisms. take in food from outside source.
captures energy from light but still needs an additional energy source(organic molecules) present such as methanol to meet all energy requirements
photoheterotroph example
green non-sulfur bacteria
obtains energy from breaking down organic molecules
chemoheterotroph example
humans, most bacteria, fungi, protozoa
metabolic pathway used by most autotrophic and heterotrophic organisms to break down glucose which is needed for energy. doesn't require oxygen but can occur when oxygen is present.
metabolic process that keeps glycolysis going by further breaking down glucose when oxygen is not present. occurs after glycolysis and oxygen is not present.
product of glycolysis
pyruvic acid
types of fermentation
homolactic acid fermentation and alcoholic fermentation
homolactic acid fermentation
pyruvic acid is converted to lactic acid, creating foods such as yogurt and cheese
alcoholic fermentation
pyruvic acid is converted to ethyl alcohol. yeast does this to make bread, wine, beer, etc.
aerobic metabolism. occurs when oxygen is present and further breaks down pyruvic acid created during glycolysis.
the amount of energy released in respiration as compared to that of initial metabolism of glucose
pyruvic acid
pyruvic acid ---->with O2_______
aerobic metabolism
pyruvic acid --->without O2 _______
anaerobic metabolism
anaerobic metabolism --->______ or _____
homolactic acid fermentation and lactic acid or alcoholic fermentation and ethyl alcohol
microbial growth
an increase in the number of cells that occur by cell division, not by size increase
mother cell
the cell that doubles in size to divide itself into two
daughter cell
a cell created by a mother cell splitting in half
types of microbial cell division
binary fission or budding
binary fission
a cell duplicates all its components and then divides in half to form two cells. this is asexual reproduction.
when a small new cell develops from the surface of an existing cell and separates from the parent cell.
example of a binary fission cell
example of a budding cell
four phases of growth
lag phase, log phase, stationary phase, decline phase.
lag phase
organisms don't increase in number, but are metabolically active and grow in size.
log phase
organisms adapt to their medium and grow at an exponential or logarithmic rate. cell division occurs rapidly.
stationary phase
the rate of cells dividing slows to the rate of cells dying and the number of cells remains constant.
decline phase
the medium and environment becomes less supportive for cell growth and division. the number of live cells decrease at a logarithmic rate.
when cells dont completely separate in cell division
they form tetrads, chains, sarcinaes, or grape like clusters.
group of 8
generation time
the interval between cell divisions. can be 20 minutes to 20 hours.
when cells divide exponentially, they form this group of descendants from the original cell.
the edges of a colony grow faster than the middle of a colony because
nutrients are less abundant in the middle