Bio 315: Biosynthesis, Horizontal Gene Transfer, and Mircrobial Ecology

The following statements about the Calvin-Benson Cycle are correct

• Rubisco catalyzes the carboxylation and hydrolysis of ribulose 1,5 biphosphate

• Some of the glyceraldehyde 3-phosphate molecules will be converted to glucose and amino acids

Transamination reactions can directly help produce 1)____ and 2) ____

1. Amino acids

2. TCA intermediates

Syntrophy occurs in an association when

Two organisms benefit from each pther through non-specific interactions

Anaplerotic reactions regeneraste intermedicates from the _____

TCA

The highest number of bacteria is present in the

Neuston

Ribose 5-phosphate is a precursor for the synthesis of the amino acid histidne. It is also a precursor for the synthesis of:

RNA and DNA

Following eutrophication, a lake will contain _____ numbers of Cyanobacteria compared to a oligotrophic lake.

Lower

The ____ pathway rregenerates ribulose 1,5 biphosphate.

Pentose phosphate

Since Rhizobium uses chemotaxis to swim towards flavenoids, we can infer that it has a flagella and that it will increase ____ rotation to get to the flavenoid source.

Counterclockwise

Freshwater layer containing many organisms at air/water interface

Neuston

Freshwater lsyer containing many Cyanobacteria and Algae

Epilimnion

Freshwater layer containing many heterotrophs

Thermocline

Freshwater layer containing photosynthetic sulfate reducers

Hypolimnion

Freshwater layer containing few organisms

Benthos

The marine environment with the lowest density of microrganisms is the

Benthos

All of the following mechanisms of horizontal gene transfer involve the transfer fo single stranded DNA:

Conjugation and Transformation

Nitrogen fixation is found only in a few organisms and is tightly regulated because

Nitrogen fixation is energy-intensive

Glucose-6-phosphate needs to be oxidized and corboxylated before being converted into ribulose 5-phosphate

Oxidize

Production of reduced nitrogen (NH3) by nitrogenase is _____ by oxygen

Not affected

SPI-1 with a different G-C content than the rest of the Salmonella chromosome, is necessary for:

Invasion of the intestinal epithelial cells

Actinomycete that produce antimicrobial peptides that kill surrounding bacteria (that provided the actinomycete nutirents) is an exmaple of

Amensalism