exam 3: major transitions

Question 1

Which of the following statements regarding complexity is true?

Answer 1

knowing the function of a component of a living system can provide insights into the structure and organization of the living system

Question 2

Which of the following major transitions proposed by John Maynard Smith and Eörs
Szathmary (1997) most likely occurred first?

Answer 2

the origin of the first cells

Question 3

Which of the following is not an organelle that is thought to be the result of endosymbiosis?

Answer 3

golgi apparatus

Question 4

According to the endosymbiotic theory, early eukaryotes acquired the mitochondrion from a
symbiotic bacterium. What happened to the bacterial genes

Answer 4

some bacterial genes were transferred to the nucleus, some were lost, and some were comprised the mitochondria genome

Question 5

The transition from unicellularity to multicellularity

Answer 5

must convey a selective advantage to individuals if it is to occur

Question 6

What is the chemical signal for slime mold amoebas to aggregate

Answer 6

cyclic amp

Question 7

Which of the following statements about multicellularity is true?

Answer 7

multicellularity has evolved many times in eukaryotes

Question 8

A somatic cell is

Answer 8

cells other than sex cells

Question 9

Wilson (1980) defined a social group as which of the following

Answer 9

a group of conspecific individuals that affect each other’s fitness

Question 10

Which process was responsible for the evolution of chloroplasts?

Answer 10

secondary endosymbiosis

Question 11

Which statement regarding the evolution of multicellularity is FALSE

Answer 11

most plants and animals are thought to have evolved through the coming tgt route

Question 12

The complete division between soma and germ-line cells may have been an evolutionary
response to which of the following selective pressures

Answer 12

certain cells acting as cheaters that over-represent themselves in the next generation

Question 13

Which of the following best describes a cost of group living

Answer 13

increased energy expenditure
increased competition for resources

Question 14

Put the following major transition events in eukaryotes in order from most ancient to most
recent.
I. Origin of chloroplasts
II. Gene transfer from the mitochondrial precursor to the nuclear genome
III. Evolution of multicellularity
IV. The expression of genes in Asgard archea that are now called “eukaryotic signature
proteins

Answer 14

IV. The expression of genes in Asgard archea that are now called “eukaryotic signature
proteins

I. Origin of chloroplasts

II. Gene transfer from the mitochondrial precursor to the nuclear genome

III. Evolution of multicellularity

(4,1,2,3)

Question 15

Based on the figure, what date of origin would you predict for organisms with around 100
different cell types?

Answer 15

500 million years ago

Question 16

How do groups offer protection in foraging?

Answer 16

large groups draw the attention of predators

many eyes detect predators more quickly

Question 17

Why are many of the benefits of group living centered around foraging and predation?

Answer 17

fitness benefits have been shown to accrue by group living including improved foraging, decreasing predation risk, conserving heat and water, conserving energy used in movement.

Question 18

Which of the following is characteristic of an individual

Answer 18

it is an integrated and indivisible whole