Mud, Lake Water, or a Sewage Sample Inoculated into Mineral

question 22

Multiple Choice

Mud, lake water, or a sewage sample inoculated into mineral salts medium supplemented with an organic acid as the carbon source, lacking fixed or organic nitrogen, and incubated anoxically in the light invariably selects for

• A) purple nonsulfur bacteria.
• B) purple sulfur bacteria.
• C) nitrifying bacteria.
• D) green nonsulfur bacteria.

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Definitions:

Fertilized Egg

A cell formed by the combining of a male and female gamete (sperm and egg) which then begins cell division to develop into an embryo.

Gametes

Reproductive cells (sperm in males and eggs in females) that carry half the genetic information of an individual and can combine to form a new organism.

Zygotes

The initial cell formed when a new organism is produced by the union of sperm and egg cells, representing the earliest developmental stage of the embryo.

Alleles

Different versions of a gene that determine distinct traits that can be passed from parents to offspring.