Nutrition

Question 0

Important cations

Answer 0

K, Mg, Ca, Fe

Mg- enzyme activation
Fe- cytochromes, electron carrying proteins

Question 1

Macroelements necessary for life

Answer 1

• needed to make carbohydrates, proteins, lipids, RNA, DNA
• SCHNOP(s)
• –sulfur, carbon, hydrogen, nitrogen, oxygen, phosphorus

Question 2

Trace Elements

Answer 2

• found on glassware, water etc
  Mn, Zn, Cu, Co, Mo, Ni

*found in enzymes and enzyme cofactors

Question 3

Specialized requirements

Answer 3

Diatoms require silicic acid for cell wall (contains silica)

Question 4

Micro organisms and Carbon Source

Answer 4

Used to make carbohydrates, other organic molecules
Ultimate source of C= CO2
Plants and microorganism can “fix” carbon dioxide
We can’t! We incorporate CO2 into organic compounds

Question 5

Heterotrophs

Answer 5

Use preformed organic molecules as C source

Question 6

Autotrophs

Answer 6

Principle C source is CO2

Question 7

Microorganisms and Scavengers

Answer 7

Probably all naturally occurring organic molecules can be broken down by some microorganism ( plastics, DDT, degraded slowly if at all)

Some fastidious (1 molecule= carbon source)

Question 8

Prototroph

Answer 8

Microorganism with typical nutritional requirements for its species

Question 9

Auxotrophs

Answer 9

Mutation (lost ability to synthesize an essential molecule)

Question 10

Phototroph

Answer 10

Uses light as energy source, traps light energy during photosynthesis (CO2 is sole C)

Question 11

Chemotroph

Answer 11

Produces energy by oxidizing chemical compounds

Question 12

Organotroph

Answer 12

Extracts electrons or protons from organic compounds

Question 13

Lithotroph

Answer 13

“Rock eaters”

Reduces inorganic substances to produce electrons or protons

Question 14

Photoorganotroph autotrophs

Answer 14

Photosynthetic, use organic molecules for electrons and hydrogen donors

Question 15

Chemolithotrophic heterotrophs

Answer 15

Oxidize inorganic compounds, both for energy and as sources for electrons, hydrogen use CO2 as C source

Question 16

Photolithotrophic heterotrophs

Answer 16

Photosynthetic, use water or other inorganic sources as electron donors, use CO2 as C source

Question 17

Chemoorganotrophic autotrophs

Answer 17

Use organic compounds for energy, hydrogen, electrons as carbon donors

Question 18

Nitrogen Requirments

Answer 18

Used for DNA and RNA, amino acids,
NH3 ammonia
NO3 nitrate, many bacteria reduce to NH3 , fertilize soil with nitrates
N2 “fixing” nitrogen, certain bacteria convert it to nitrate

Question 19

Phosphorus Requirments

Answer 19

Used for amino acids, methionine and cytosine, some carbohydrates
Usually incorporated at SO4-

Question 20

Defined Medium

Answer 20

Every compound and it’s concentration is known

E. Coil can grow in medium with only:
 Glucose
 Sodium phosphate
 Potassium phosphate
 Ammonium sulfate
 Magnesium sulfate
 Ferrous sulfate
 Calcium chloride
 pH 6.8

Question 21

Complete Medium

Answer 21

“Enriched”
Amino acids, partially digested proteins, carbohydrates
Ex. TSB and TSA

Question 22

Selective Medium

Answer 22

Selects for one kind of microorganism by inhibiting others

Ex Hektoen media contains salts, only those adapted will survive
Eosin, methylene blue (EMB) inhibit growth of gram +, only gram - grow
Inhibits gram-, only gram + will grow

Question 23

Can medium be differential and selective? Explain!

Answer 23

Levine EMB agar
Medium has inhibitors of gram + growth
Medium also has lactose and dye, colonies that ferment lactose turn pink