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Flashcards in Bacteria Lab Deck (13):
1

What are 3 safety procedures for this lab

1) disinfect the bench before and after the lab
2) be sure to wash your hands before and after the lab AND if you leave the lab for any reason
3) all open cuts or wounds must be covered

2

What is a gram positive bacteria

They have 3 layers, high peptidoglycan, negative strand test, and turn purple in a strand test

3

What is gran negative bacteria

Low peptidoglycan, 2 layers, positive strand test, turn pink during a strand test

4

Scientific name for blue green algae

Cyanobacteria

5

Why do blue green algae vary in colour

They have accessory pigments, certain concentrations determines the overall colour

6

What is nitrogen fixation and what 2 organisms can carry it out

Nitrogen fixation- changes atmospheric nitrogen into ammonia

2 organisms that do this are
- gleotrichia
-Nostoc

7

Describe the structure of oscillatoria

A long finger like structure that has line through it, these are separation disks

8

Why is Nostoc different from other blue green algae

They are able to large spherical shapes with thousands of colonies in a gelatinous matrix

9

What is the purpose of akinetes in gleotrichia

Protect, as they can survive harsh conditions and be inactive spores for 70-80 years

10

Are Cyanobacteria the same as plant cells

No cyanobacteria are prokaryotes, they do not have organelles like plants, they photosynthesize by unique fold in their membrane

11

What are heterocysts

Heterocsyts preform nitrogen fixation

12

Is gram negative or gram positive more resistant to bacteria

Gram negative are more resistant

13

How does a strand test work?

KOH breaks down the walls allowing the bacteria to come out