Exam 1

Question 1

Natural Selection

Answer 1

variational change where some individuals have an allelic variation that grants them higher fitness than other individuals, therefore their alleles are passed to the next generation at a higher frequency

Question 2

Genetic Drift

Answer 2

Variational change caused by random sampling error when individual organisms reproduce

Question 3

Injury to Somatic Cells

Answer 3

Not a force for evolution as it does not have a direct impact on the population

Question 4

Mutation in Germ Cells

Answer 4

Transformational change that occurs either as a mistake during DNA replication or an error when damaged DNA is repaired incorrectly

Question 5

All genetic variation in biological populations originates as..

Answer 5

a mutation

Question 6

What are all the biological organisms that share a single common ancestor?

Answer 6

shark
cyanobacterium
whale
chicken
velociraptor

Question 7

7. In one of our reading selections Stephen Jay Gould argues that science is good for some human endeavors and religion and philosophy are good for others and that these two realms should be kept largely distinct from one another. He calls this idea ____________.

Answer 7

separate magisteria

Question 8

A body of scientific research that has been tested, refined and is well supported by multiple lines of evidence is called a

Answer 8

theory

Question 9

When did the first living organisms evolve on the planet earth?

Answer 9

3.5 billion years ago

Question 10

What is the best data to support the date in the above question?

Answer 10

relative dating of the oldest known fossils (stromatolites)

Question 11

Legal decisions regarding the teaching of creationism in public schools have focused on the separation of church and state and

Answer 11

non-scientific nature of creationism

Question 12

Which of the following molecules, common in todays atmosphere, was largely absent form the atmosphere of prebiotic earth?

Answer 12

oxygen (O2)

Question 13

What is the primary source of the molecule referenced in the question above?

Answer 13

photosynthesis

Question 14

The first molecular steps towards the origin of life on earth were

Answer 14

RNA

Question 15

Viruses originates as living cells that shared a common ancestor with all other living organisms slowly evolved to become parasites of other living cells and lost the ability to reproduce and gather their own energy.

Answer 15

The statement represents the reduction hypothesis of viral origin and is one of three possible explanations for the origins of viruses

Question 16

How did early ancestors of modern green algae and plants evolve the ability to photosynthesis?

Answer 16

An endosymbiotic event resulted in a prokaryotic cell that could photosynthesize living within these eukaryotic cells this eventually became the modern chloroplast

Question 17

Pterosaurs

Answer 17

an extinct group of diapsids, these were the first vertebrates to evolve flight

Question 18

Pigeon

Answer 18

one representative of a now diverse group of dinosaurs that survived the end cretaceous extinction 65 million years ago

Question 19

Ammonites

Answer 19

An extinct group of mollusks, that are closely related to modern nautilus and squid

Question 20

Sarcopterygii

Answer 20

This group represents the closest relatives of tetrapod vertebrates and has a few extant species including lungfish and coelacanths

Question 21

Which group of animals was the first evolve flight?

Answer 21

insects

Question 22

An organic sample of unknown age has 8 picograms of radioactive carbon. A modern sample of the same size and composition contains 128 picograms of radioactive carbon. If the half-life of radioactive carbon is 5,000 years, how old is the original sample?

Answer 22

20,000 years old

Question 23

Nodes in a phylogeny represents the most recent common ancestor of descendant branches

Answer 23

true

Question 24

The relatively rapid appearance of major groups of animals in the fossil record is known as the

Answer 24

cambrian explosion

Question 25

What group would be the least important if you were interested in studying the origin and early history of vertebrates?

Answer 25

ammonites

Question 26

Which is not a trend observed during the evolution of horses?

Answer 26

increase in average number of offspring for each pregnancy

Question 27

Which of the following is the closest relative of the family Equidae (horses, donkeys, and zebras) ?

Answer 27

rhinocerotidae (rhinoceroses)

Question 28

Why was a bipedal gait critical for the evolution of birds?

Answer 28

it released the forelimbs from the ancestral function of supporting body weight while walking or running

Question 29

Indohyus is an early ancestor of modern whales but it doesnt look much like modern whales. What morphological feature best establishes Indohyus as a whale ancestor?

Answer 29

distinctive shape of three ear bones

Question 30

Only extant species can be included in phylogenetic analyses

Answer 30

false

Question 31

Instead of branching tree like patterns, relationships between individuals in sexually reproducing species are better represented in network like diagrams. This is also true for relationships between species of

Answer 31

bacteria

Question 32

A polytomy represents

Answer 32

uncertainty about the relationships within a particular group

Question 33

Homology

Answer 33

its when two structures are similar due inheritance form a common ancestory

Question 34

What are two explanations for homoplasy?

Answer 34

convergent evolution of similar traits in separate lineages loss of an ancestral feature in a subset of descendants

Question 35

Which of the following features of humans could be best classified as vestigial?

Answer 35

erector pili muscles

Question 36

The ability to use language is the one feature that sets apart homo sapiens from all other species on earth

Answer 36

false

Question 37

Which of the following is the best explanation for why a structure becomes vestigial?

Answer 37

A species is living in an environment where a previously useful structure no longer provides a clear advantage, when random mutations occur that impact this structure they are more likely to be kept in the population due to natural selection.

Question 38

Which of the following is the closest relative of humans?

Answer 38

homo erectus

Question 39

Modern genetic analysis of the human species suggests that all humans had a common maternal ancestor somewhere between

Answer 39

100 and 200 thousand years ago

Question 40

Which species can be classified as homonids?

Answer 40

homo sapiens australopithcus afarensis gorilla gorilla

Question 41

which of the following is the best defining feature of the hominis

Answer 41

bipedalism

Question 42

Some humans, particularly those with ancestors from Europe and the Middle East, carry genetic markers that are common in Homo neanderthalensis. What is the best explanation for this?

Answer 42

introgression due to limited mating between these populations when they overlapped