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Flashcards in lecture 1.3 Deck (54):
1

How do Prokaryotes differ from Eukaryotes?

most lack internal membrane systems

2

What are the different shapes?

cooci, bacilli, vibrios, spirilla, spirochetes

3

Cocci=

round sphere

4

How is the arrangment determined?

determined by plane of division
determined by separation or not

5

diplococci=

pairs of spheres

6

streptococci=

chains of spheres

7

staphylococci=

grape like clusters

8

tetrads=

4 cocci in a square

9

sarcinae=

cubic configuration of 8 cocci

10

Bacilli=

rods

11

coccobacilli=

very short rods

12

vibrios=

resemble rods, comma shaped

13

spirilla=

rigid helices

14

spirochetes=

flexible helices

15

mycelium=

network of long, multinucleate filaments

16

pleomorphic=

organisms that are variable in shape

17

How small can a bacteria be?

0.3 μm (Mycoplasma)

18

How large is the average rod?

average rod – 1.1 - 1.5 x 2 – 6 μm (E. coli)

19

How large can bacteria be?

– 600 x 80 μm (Epulopiscium fishelsoni)

20

Why is size/shape important?

important for nutrient uptake
surface to volume ratio (S/V)

21

What typically happens to cells when they are under stress?

When cells are under stress, they typically get rounder and smaller

22

What is an advantage to being small besides S/V ratio

small size may be protective mechanism from predation

23

What are the common features of Bacterial Cell Orginization? (in regards to layers)

Cell envelope – 3 layers
Cytoplasm
External structures

24

What does the Bacterial Cell Evelope contain?

Plasma membrane
Cell wall
Layers outside the cell wall

25

What are some plasma membrane functions?

Encompasses the cytoplasm
Selectively permeable barrier
Interacts with external environment

26

How does the plasma membrane interact with the external barrier?

receptors for detection of and response to chemicals in surroundings
transport systems
metabolic processes

27

amphipathic lipid has what two parts?

polar ends (hydrophilic – interact with water)
non-polar tails (hydrophobic – insoluble in water)

28

Peripheral in regards to the plasma membrane=

loosely connected to membrane
easily removed

29

Integral in regards to the plamsa membrane=

amphipathic – embedded within membrane
carry out important functions
may exist as microdomains

30

bacterial membranes do not contain sterols, but contain what?

hopanoids, sterol like molecules

31

What are the macronutrients?

C O H N S P K Ca Mg and Fe

32

Where can you find C O H N S P?

organic molcules such as proteins, lipids, carbohydrates, and nucleic acids

33

What do you use K Ca Mg and Fe for?

cations used in enzymes and biosynthesis

34

What are the micronutrients?

Mn Zn Co Mo Ni and Cu

35

Where are micronutrients found?

Ofrten in the water or media components

36

What do micronutirents serve for?

Serve as enzymes and cofactors

37

What are the growth factors?

organic compounds
essential cell components (or their precursors) that the cell cannot synthesize
must be supplied by environment if cell is to survive and reproduce

38

What are the classes of growth factors?

amino acids
purines and pyrimidines
vitamins
heme

39

What are amino acids used for (growth factor)

protien synthesis

40

What are purines and pyrimidines used for? (growth factor)

nucleic acid synthesis

41

What are vitamins used for? (growth factor)

enzyme cofactors

42

What is passive diffusion

Molecules move from region of higher concentration to one of lower concentration between the cell’s interior and the exterior

43

What molecules travel by passive diffusion

H2O, O2, CO2, glycerol, ethanol

44

What is facilitated diffusion

movement of molecules is not energy dependent
direction of movement is from high concentration to low concentration
size of concentration gradient impacts rate of uptake

45

How is facilited diffusion different from passive diffusion?

uses membrane bound carrier molecules (permeases)
smaller concentration gradient is required for significant uptake of molecules
effectively transports glycerol, sugars, and amino acids
more prominent in eukaryotic cells than in bacteria or archaea

46

What defines active transport?

energy-dependent process
move molecules against the gradient
concentrates molecules inside cell
involves carrier proteins (permeases)
--carrier saturation effect is observed at high solute concentrations

47

What defines an ABC Transporter?

Consist of
- 2 hydrophobic membrane spanning domains
- 2 cytoplasmic associated ATP-binding domains
- Substrate binding domains

48

What is the energy for active transport?

--ATP or proton motive force used

49

What are the types of Secondary Active Transport?

protons
symport – two substances both move in the same direction
antiport – two substances move in opposite directions

50

symport=

two substances both move in the same direction

51

antiport=

two substances move in opposite directions

52

How does secondary active transport get its energy?

Use ion gradients to cotransport substances

53

What is group translocation?

Energy dependent transport that chemically modifies molecule as it is brought into cell

54

How do micororganisms get iron into the cell

siderophore complexes with ferric ion (iron)