In humans, albinism (unpigmented skin, hair, and eyes) is due to an enzymatic deficiency, and it is an autosomal recessive trait. Suppose that in a small country of one million people (“Generation 1”), there are 500 aa albinos and 9000 Aa heterozygous carriers. In the next generation of 1 million individuals (Generation 2), what are the expected numbers of aa albinos and Aa carriers? (Assume random mating and all other HardyWeinberg conditions.)

#Question id: 11373

#Unit 9. Diversity of Life Forms

Which of the following obtain energy by oxidizing inorganic substances; energy that is used, in part, to fix CO2?

#Question id: 11374

#Unit 9. Diversity of Life Forms

Which of the following use light energy to generate ATP, but do not release oxygen?

#Question id: 11392

#Unit 9. Diversity of Life Forms

Modes of obtaining nutrients, used by at least some bacteria, include all of the following except

#Question id: 11393

#Unit 9. Diversity of Life Forms

Given that the enzymes that catalyze nitrogen fixation are inhibited by oxygen, what are two ʺstrategiesʺ that nitrogen-fixing prokaryotes might use to protect these enzymes from oxygen?

1.  couple them with photosystem II (the photosystem that splits water molecules)

2.  package them in membranes that are impermeable to all gases

3.  be obligate anaerobes

4.  be strict aerobes

5.  package these enzymes in specialized cells or compartments that inhibit oxygen entry

#Question id: 11394

#Unit 9. Diversity of Life Forms

Foods can be preserved in many ways by slowing or preventing bacterial growth. Which of these methods would not generally inhibit bacterial growth?

#Question id: 11395

#Unit 9. Diversity of Life Forms

Mitochondria are thought to be the descendants of certain alpha -proteobacteria. They are, however, no longer able to lead independent lives because most

genes originally present on their chromosome have moved to the nuclear genome. Which phenomenon accounts for the movement of these genes?