Lecture 8

Question 1

Agar Slants

Answer 1

Used to store a culture for up to a year. It is a test tube with the culture slanted up the side. This is what we use in lab.

Question 2

Binary Fission

Answer 2

The way bacteria divide. The daughter cells are identical. DNA replicates, moves to ends of cell and the cell splits.

Question 3

Biofilm

Answer 3

In nature bacteria usually grows as mixed-species biofilms. They have to attach to the surface and the more attach to them and then they become specialized. Planktonic cells lose flagella and the clump together with glycolyx or pili and then differentiate and then the middle cells form flagella and break free and the process is repeated.

Question 4

Clonal

Answer 4

Or isogenic. When a streak plate is used to separate cultures the speices is clonal

Question 5

Enrichment Culture

Answer 5

Specially designed medium allows one organism to grow better than others. Used to isolate one particular species of organism from a mixed sample

Question 6

Freezer Culture

Answer 6

Most commonly used. Will last several years. It is stored in >10% glycerol at -70C. Water will lysis cells and glycerol won’t. Stored in plastic tubes(like my DNA was in)

Question 7

Growth Factor

Answer 7

Amino Acids, Fatty acids, Vitamins, & Nucleotides. Some bacteria make their own (prototrophs) some bacterial must have them provided (auxotrophs)

Question 8

Lyophilize

Answer 8

Freeze Dry. Used to create pure colonies. Not for all organisms. Can use set on a shelf. Good for years.

Question 9

Nutritionally Fastidious

Answer 9

Must have their growth factors provided for them

Question 10

Planktonic

Answer 10

Cells in biofilm formation. They lose their flagella and then build up and then reform it and break away.

Question 11

Complex Media

Answer 11

At least one ingredient is not defined(has no chemical formula). Often contain extracts of various things. Commonly used to grow fastidious organisms. (Like orange juice)

Question 12

Defined Media

Answer 12

All ingredients can be listed by chemical formula and by amount

Question 13

Differential Media

Answer 13

Cause different organisms to produce different reactions. Blood agar. Hemolysis and pH indicators

Question 14

Selective Media

Answer 14

Prevent growth of some organisms. Salt agars >5%

Question 15

Psychrophile

Answer 15

Optimal Grow temperature. Min:<20. optimal:10-15. Grows best at relatively low temperatures

Question 16

Psychrotroph

Answer 16

Optimal growth temperature. Min:0. Max:>25. optimal: 15-30. Able to grow at low temps but prefers moderate temps (cold)

Question 17

Mesophile

Answer 17

Optimal growth temperature. Min:10-15. max: <45. optimal:30-40. Most bacterial. especially those that are associated with warm-blooded animals (middle)

Question 18

Thermophile

Answer 18

Optimal growth temperature. Min: 45. Max: >100. Optimal: 50-85. Wide variations in optimal temp and max temp

Question 19

Hyperthermophile

Answer 19

Optimal growth temperature. Min:65. Max:110-112. Optimal:90-110. Optimum often above boiling.

Question 20

Shake Tube

Answer 20

It is a tube that shows how the oxygen affects the culture in the tube

Question 21

Fluid Thioglycollate Medium

Answer 21

Same as a shake tube. Shows how the oxygen affects the culture in the tube

Question 22

Obligate Aerobe

Answer 22

Needs oxygen. Respiratory. Top of tube

Question 23

Obligate Anaerobe

Answer 23

Oxygen kills them. Fermented. Bottom of the tube

Question 24

Facultative Anaerobe

Answer 24

Can use oxygen but doesn’t need it. Respiratory and fermented. Separated throughout the tube

Question 25

Microaerophile

Answer 25

Needs oxygen but it also kills them. The culture needs less oxygen. Respiratory. Culture in the middle of the tube

Question 26

Aerotolerant

Answer 26

Doesn’t use oxygen but it doesn’t kill them. Fermented. More at the bottom then the top but it is spread out

Question 27

Catalase

Answer 27

a common enzyme found in nearly all living organisms exposed to oxygen. It catalyzes the decomposition of hydrogen peroxide to water and oxygen

Question 28

Superoxide Dismutase

Answer 28

enzymes that catalyze the dismutation of superoxide (O2−) into oxygen and hydrogen peroxide. Thus, they are an important antioxidant defense in nearly all cells exposed to oxygen

Question 29

Acidophile

Answer 29

Organisms that thrive under acidic conditions. Usually a pH of 2 or below, Pumps out excess H+. Prevents H+ from getting in the cell

Question 30

Neutrophile

Answer 30

Organisms thrive in a pH of about 7.

Question 31

Alkalophile

Answer 31

Organisms that thrive in basic conditions. Use Na+ gradient rather than H+. Don’t have PMF

Question 32

Osmolarity

Answer 32

Must avoid lysis. Must avoid plasmolysis. Can absorb salt by binding to protein surface charges. Can synthesize osomprotectants

Question 33

Lysis

Answer 33

Cell explodes

Question 34

Plasmolysis

Answer 34

the process in plant cells where the cytoplasm pulls away from the cell wall due to the loss of water through osmosis. This occurs in a hypertonic solution

Question 35

Halophile

Answer 35

Organisms that live in a high salt content

Question 36

Osmoprotectant

Answer 36

small molecules that act as osmolytes and help organisms survive extreme osmotic stress

Question 37

Auxotroph

Answer 37

a mutant organism that requires a particular additional nutrient that the normal strain does not.

Question 38

Prototroph

Answer 38

A wild type that makes its own nutrient

Question 39

Chemotroph

Answer 39

Obtains energy from Delta G redox reactions. Energetic electrons

Question 40

Phototroph

Answer 40

Receives energy from the sunlight (photosynthesis) excited by light

Question 41

Lithotroph

Answer 41

Reduced inorganic compounds. Lito=mineral source. That’s where electrons come from.

Question 42

Organotroph

Answer 42

Reduced organic compounds. That’s where electrons come from

Question 43

Autotroph

Answer 43

CO2 and occasionally CO. Calvin Cycle. That’s where carbon comes from

Question 44

Heterotroph

Answer 44

Organic compounds. C-H bonds. That’s where carbon comes from