Lecture 1

Question 1

What is the definition of evolution?

Answer 1

A change in genetic frequencies

Question 2

What is the definition of natural selection? (our class definition)

Answer 2

The mechanism of evolution and how it occurs

Question 3

Which statement does not describe the natural selection example discussed in class (the one about the black and brown mice)?

Answer 3

There are two different colored mice, some black and others tan, sitting on a black rock. Because tan mice are more visible to predatory birds as compared to black mice, the tan mice are eaten in a higher frequency than the black mice, with only the surviving mice reaching reproductive age and leaving offspring. Because black mice had a higher chance of leaving offspring than tan mice, the next generation contains a higher percentage of black mice than tan mice.

Question 4

According to the video Natural Selection, if there are organisms which are considered the same species, which statement describes one of the things they can do?

Answer 4

• They can breed with each other
• They pass down their DNA to their offspring

Question 5

According to the video Natural Selection, what does fitness mean in the biological sense?

Answer 5

The ability of an individual to produce surviving fertile offspring relative to that ability in other individuals in the population.

Question 6

What is artificial selection?

Answer 6

When humans pick the genes they want expressed

Question 7

Fossils provide direct evidence of evolution. How does one make a fossil?

Answer 7

The organism has to be buried cement, second the calcium has to mineralize, the surrounding cement has to harden to form rock by applying a lot of pressure

Question 8

What is a difference between relative and absolute dating of fossils?

Answer 8

relative dating was done in darwin’s day and they were dated by there position with respect to one another, higher means younger lower means older

absolute dating looking at radioactive decay by looking at half life’s, the amount of time for one half of the time to be transformed from something to decay

Question 9

What is the definition of a homologous structure?

Answer 9

structures with different appearances and functions that all derive from the same body part in a common ancestor

Question 10

Anatomical evidence for evolution is extensive and persuasive. How do the presence of homologous structures on certain species support this statement?

Answer 10

You can use it to see how closely something is related

Question 11

What is the definition of a vestigial structure?

Answer 11

body part of structure that is no longer used by an organism but it can explain as holdovers from the passed

Question 12

Which statement describes an examples of a vestigial structure?

Answer 12

A body part or structure that is no longer used by an organism but it can explain as holdovers from the past.

Question 13

According to the video Molecular Evolution: Genes and Proteins, when scientists compare the entire genome of backer’s yeast and a worm, what did they find?

Answer 13

• Human appendix: Useless to us humans. Rats however, still use the appendix in their digestive system, holding extra things inside their body when doing digestion. Humans probably used it in the same way.
• Whales have a pelvic bone, having no function and being very weak. Them having it exemplifies and proves how we are related to them through being both mammals.

Question 14

According to the video Molecular Evolution: Genes and
Proteins, how can the genome of cytochrome C tell us how organisms are related?

Answer 14

organisms are related to each other because it’s found in the mitochondria of every eukaryotic cell

Question 15

What is a difference between convergent and divergent evolution?

Answer 15

Convergent Evolution- occurs when species have different ancestral origins but have developed similar features bc they live in a similar location

Divergent Evolution- occurs when two separate species evolve differently from a common ancestor

Question 16

Which statement describes an example of convergent evolution?

Answer 16

Convergent: Occurs when species have different ancestral origins but develop similar features due to them living in the same location.

Question 17

Which statement describes an example of divergent evolution?

Answer 17

EX: Darwin’s finches in the galapagos. Only 1 finch species came to the Galapagos from Ecuador led to around 20 different species of Finches in the Galapagos islands.

Question 18

Which statement accurately describes the current theories for where life originated on earth four billion years ago?

Answer 18

• At the ocean’s edge: Life arose at bubbles that were constantly forming at the ocean’s edge (RNA become DNA that became an organism- life arose in bubbles).
• Under frozen oceans: Discounted by the fact that early Earth was warm instead of cold.
• Volcanic activity & Earth’s crust (simulated this in a lab, and made peptides)
• Within clay- because of its positive charge, if a negative charge is introduced it can cause a bonding structure and end up in a life form

Question 19

Which theory is regarded as the most viable (currently) for where and how life originated on Earth? Why?

Answer 19

Deep sea events, because they have everything needed to evolve

Question 20

What is the definition of a mass extinction?

Answer 20

extremely sharp decline in species diversity

Question 21

Which of these is not a mass extinction which occurred in the past?

Answer 21

Past mass extinctions: Ordovician, Devonian, Permian, Triassic, Cretaceous

Question 22

The most severe extinction occurred at the end of the ____ period approximately 250 million years ago
(96-98% of all plant and animals went extinct).

Answer 22

permian

Question 23

We are currently in the sixth mass extinction called the

Answer 23

Anthropocene