Text Exam I. 1

I.                    Bacteria
a.       __major groups of Bacteria, ranging from __ that __to __ such as cyanobacteria and purple and green bacteria

II. Cyanobacteria: Important from Ecological and Evolutionary Views
a. Partake in the global __ and __ and represent one of the major evolutionary lines of Bacteria

a.       Photosynthetic cyanobacteria have __, together with __and accessory pigments called __(two kinds)
                                                              i.      What are they?


b.      Cells of cyanobacteria have several __, __to each other
                                                              i.      These membranes are __ that resemble those found in chloroplasts—and, in fact chloroplasts correspond in size to an entire cyanobacterial cell
1.       The main storage product of cyanobacteria is __

a.       Many cyanobacteria produce a __that bidns groups of cells/ filaments together
                                                              i.      Colors of the sheaths in different species __
1.       “blue-green algae” are not __and are about __
b.      They may often form __and grow in large amsses 1 m or more in length
                                                              i.      Some are __, some have __, and few have __

1. Division--> subunits separate to __

a. Cells of cyanobacteria are joined only by __ or __, so that each cell leads an __life
ii. Some filamentous cyanobacteria are __, doing what?
1. Some segments called __break off from a cy. Colony and glide away from their parent colony at rapid rates

a.       This movement may be connected with the __  through small pores in the cell wall, together with the production of __ in one of the surface layers of the wall
                                                                                                                                      i.      Some cyanobacteria exhibit __

 b.      Where They Live
                                                              i.      Despite the ‘7500’ species, there may be as few as __
                                                            ii.      Like other bacteria, they sometimes grow under very __ (hot springs, arctics, etc./ not in acidic places)
                                                          iii.      Layered chalk deposits called __ (2.7 billion years) are produced when colonies of cyanobacteria bind __

1.       Today, they are in only a few places
a.       Yet, their presence indicates what?
                                                                                                                                      i.      Most ancient ones were probably made by __

                                                              i.      Many marine cyanobacteria occur in __, like coralline algae and the shells of mollusks
                                                            ii.      Some freshwater species of cy. often deposit thick layers of __in their colonies. 

a.       Cyanobacterial Formation of Gas Vesicles, Heterocysts, and Akinetes
                                                              i.      The cells of cy. living in freshwater or marine habitats—especially plankton (on the surface)—commonly contain bright, irregularly shaped structures called __, which do what, thus allowing what? . 

1.       When several cy. can’t regulate __ properly (maybe due to fluctuating temps), they may __ and __
a.       Some cy. that form __secrete __ that are toxic to other organisms and cause death
                                                            ii.      Many genera of cy. can __[which is available for biological reactions])

                                                              i.      In filamentous cy., the __ often occurs with __, which are specialized, enlarged cells
1.       Surrounded by what?
2.       Within a __, the cell’s internal membranes are reorganized into a __

a.       Heterocysts are low in __, and they lack __, so the __ that occurs in these cells doesn’t result in the __      
                                                                                                                                      i.      The oxygen that is present is either rapidly __, a by-product of nitrogen fixation, or __
1.       __, the enzyme that catalyzes the nitrogen-fixing reactions, is sensitive to the presence of oxygen, and nitrogen fixation is __

a.       __have small __connections—__—with adjacent vegetative cells
2.       The products of __ are transported through the __from the __to the vegetative cells, and the products of photosynthesis move in the __ through these same connections, from the __ to the __.

1.       Among cy. that fix nitrogen are free-living species such as __, which lives in certain __
a.       They account for ¼ of the total __ there
2.       __cy. are also important in __
a.       In Asia, they helped with growing rice without fertilizers
                                                                                                                                      i.      Members of the genus Anabaena often occur in association with the small, floating water fern Azolla, which forms masses on __

                                                              i.      Cy. occur as __within the bodies of a vast number of species: amoebas, sponges, etc. and also act photosynthetically in lichens
1.       Some __cy. lack a __, in which case they function as __
2.       __ cy. divides at the same time as its host cell by  a process similar to __
                                                            ii.      In addition to __, some cy. form resistant spores called __, which are enlarged cells surrounded by thickened envelopes
1.       They are resistant to heat and drought and thus allow the cyanobacterium to survive during unfavorable periods

a.       Prochlorophytes contain Chlorophylls a and b and Carotenoids
                                                              i.      The __are a group of photosynthetic bacteria with __ and __, but no __.
1.       Only three discovered: What are they?

Prochloron

Prochlorococcus

Prochlorothrix

a.       Purple and green Bacteria and Photosynthesis
                                                              i.      Represent second major group of __after cy.
1.       The overall __ and the __ used by these bacteria differ from __ and __.

What is the difference between PnG bacteria and Prochlorophytes and Cy.

Differences in photosynthesis

Purple and green bacteria
a.       The __are ancestors of individual __—__
                                                                                                                                      i.      Unlike p & g bacteria, photosynthetic autotrophs (plants and algae), as well as cy. and prochlorophytes, have __

                                                              i.      Colors characteristic of photosynthetic bacteria are associated with the presence of __ that function in photosynthesis
1.       In two groups of purple bacteria= __
2.       In cy., the pigments are __, which aren’t in p & g bacteria
                                                            ii.      Purple and green bacteria are subdivided into those that __
1.       __plays same role in photosynthesis that water does 

                                                              i.      Purple nonsulfur and green nonsulfur bacteria, which are able to use __ at only low levels, also use organic compounds as __
1.       These compounds are fatty acids, alcohols, etc.

1.       Because of their requirement for __or a similar substrate, the purple sulfur and green sulfur bacteria can grow only in habitats containing large amounts of __, recognizable by the sulfurous odor
a.       In these bacteria, __ may accumulate as deposits within the cell