Lecture 3: Bacterial Anatomy And Growth

Front 1

What is flagella composed of?

Back 1

flagellin

Front 2

flagella, which is composed of flagellin, is a gear with ____ and ___ in the membrane

Back 2

rings and rod

Front 3

The direction of flagellar motion determines ____ vs. _____

Back 3

run vs. tumble

Front 4

The number and placement of flagella vary by species. Bacteria can be ____, _____, ____, _____.

Back 4

monotrichous, lophotrichous, amphitrichous, petrichous

Front 5

monotrichous

Back 5

possessing a single flagellum at one end

Front 6

lophotrichous

Back 6

having a group of two or more flagella at one end

Front 7

amphitrichous

Back 7

having a single or group of flagella at both ends

Front 8

peritrichous

Back 8

having flagella at many locations over the cell surface.

Front 9

chemotaxis

Back 9

a movement toward a chemical attractant. It can be an attraction or repulsion.

Front 10

how do flagella move in bacteria?

Back 10

rotate

Front 11

how do flagella move in protozoa?

Back 11

whip

Front 12

What forms spores when nutrients are exhausted?

Back 12

A few gram-positive bacteria, especially members of the genera Bacillus and Clostridium

Front 13

Spores contains very little water and use lots of ___ to stabilize proteins and DNA.

Back 13

dipicolinic acid

Front 14

spores become _____ as soon as favorable conditions return

Back 14

vegetative

Front 15

what three things can spores survive?

Back 15

1) boiling water
2) Ethanol
3) Radiation.

*Spore have been found in mummies & fossils

Front 16

What are the steps of binary fission?

Back 16

- Chromosome duplicates
- Cell elongates
- Plasma membrane moves inward to make 2 cells

Front 17

the interval of time between successive binary fissions of a cell or population of cells (a.k.a. doubling time)

Back 17

generation time

Front 18

What is Escherichia coli's generation time?

Back 18

20 minutes

Front 19

What is Staphylococcus aureus's generation time?

Back 19

30 minutes

Front 20

What is Mycobacterium tuberculosis's generation time?

Back 20

18 hrs

Front 21

What is treponema pallidum's gneration time?

Back 21

22 hrs

Front 22

What are the four distinct phases of a typical bateria growth curve?

Back 22

- lag phase
- exponential growth phase
- stationary phase
- death phase

Front 23

Lag phase

Back 23

the phase of a bacterial growth curve prior to binary fission. No cell divisions occur.

Front 24

exponential growth phase (also known as logartithmic phase)

Back 24

the phase of a bacterial growth curve when reproduction and growth are at their highest rates. all cells are undergoing binary fission. As each generation time passes, the number of bacteria doubles and the graph rises in a straight line on a logarithmic scale

Front 25

Stationary phase

Back 25

The phase of a bacterial growth curve when the reproduction rate equals the death rate.

Front 26

death phase (also known as decline phase)

Back 26

the number of dying cells exceeds the number of new cells formed.

Front 27

What are three important factors governing growth?

Back 27

- Temperature
- Oxygen
- pH

Front 28

Bacteria have different ideal growth temperatures. Psychrophiles grow at what temperature range?

Back 28

0-20°C
psychrophiles like the cold

Front 29

Mesophiles grow at what temperature range?

Back 29

20-40°C
-ex: pathogens that grow in the human body

Front 30

Thermophiles grow at what ideal temperature range?

Back 30

40-90°C

Front 31

Hyperthermophiles grow at what ideal temperature range?

Back 31

90 up to 113°C

Front 32

Most pathogenic bacteria prefer temperatures of 35-42°C, making them ___

Back 32

mesophiles

Front 33

psychrotropic or psychrotolerant bacteria

Back 33

-can grow below normal range (still alive in the fridge)
-mesophiles that grow in the cold.
-They are not truly psychrophilic. They will survive at 0°C but prefer to grow at typical mesophile temperatures.

Front 34

aerobic bacteria

Back 34

bacteria that depends on a plentiful supply of oxygen

Front 35

anaerobic bacteria

Back 35

bacteria that live in oxygen-free environment, may die in presence of oxygen
-ex: Clostridium botulinum

Front 36

facultative bacteria

Back 36

Can grow either in presence of or reduced concentration of oxygen (majority of bacteria)

Front 37

Microaerophilic bacteria

Back 37

requires low oxygen to grow
-Ex: T. pallidum

Front 38

Capnophilic bacteria

Back 38

low oxygen and high carbon dioxide required
-ex: Neisseria, Streptococcus)

Front 39

What is the pH range of bacteria?

Back 39

2.0-9.5

Front 40

What is the preferred pH range of bacteria?

Back 40

7.2-7.4
- Human blood and tissue, perfect hosts

Front 41

Most bacteria do not grow well in: a) acid or b) base?

Back 41

acid
- Stomach acid deters bacteria
- Citrus fruits rarely contaminated w/ bacteria. molds instead!

Front 42

acidophiles

Back 42

acid-tolerant and useful for food/dairy industry
-Ex: Lactobacillus, Streptococcus

Front 43

What is most bacteria grown on?

Back 43

some type of protein nutrient broth w/ agar added

Front 44

What is added to solidify the protein nutrient broth that most bacteria grow on?

Back 44

Agar

Front 45

Enriched media

Back 45

contains special nutrients for fastidious bacteria
- Ex: Neisseria grow on chocolate agar- heated whole blood (hemoglobin)

Front 46

Selective media

Back 46

allows growth of certain bacteria while inhibiting others

Front 47

Differential media

Back 47

distinguishes one type of bacteria from another