Exam 1 - History of Earth

Question 1

The evolutionary relationship among organisms is known as

Answer 1

Phylogeny

Question 2

How long ago did the lineage leading to humans and chimps diverge from the lineage leading to gorillas?

Answer 2

7mya

Question 3

About when did the common ancestor of humans, chimps, gorillas, and orangutans last exist?

Answer 3

12.5mya

Question 4

Which trait would be least helpful in a phylogenetic analysis?

Answer 4

A trait that is altered easily by small changes in temperature

Question 5

When a single lineage divides into two, it is depicted as a split or node on a phylogenetic tree

Answer 5

True

Question 6

A homoplasy is a shared character between two or more animals that did not arise from a common ancestor

Answer 6

True

Question 7

The principle of Parsimony is

Answer 7

The simplest explanation is usually the right one

Question 8

The study and classification of biodiversity is called

Answer 8

Systematics

Question 9

Snakes, which lack limbs, evolved from vertebrates that had legs. The limbs of snakes disappeared by _____ and the backbones of snakes are a ______

Answer 9

An evolutionary reversal, synapomorphy

Question 10

Which synapomorphy unites the pigeon and the lizard?

Answer 10

Keratinous scales

Question 11

If a gene is a Hox gene, what is its most likely normal function?

Answer 11

To instruct a segment regarding what organ to form

Question 12

Two good reasons to study molecular evolution include

Answer 12

We can learn more about where we come from and who we are, and we can use this information to develop new drugs and treatments for disease

Question 13

Sexual reproduction results in new gene combinations that increase evolutionary potential

Answer 13

True

Question 14

Sexual recombination does not directly influence the frequencies of alleles but

Answer 14

It does generate new combination of alleles on which natural selection can act

Question 15

A gene family

Answer 15

Is a group of homologous genes with related functions

Question 16

Ginkgo trees are native to Asia but are now cultivated by horticulturalists widely in North America. Thus, they are divided into two geographically separated groups. According to Mayr’s framing of the biological species concept, these populations could be classified as belonging to the same species if they

Answer 16

Are still potentially capable of exchanging genes

Question 17

Which condition is least likely to lead to geographic isolation and allopatric speciation?

Answer 17

A narrow, but deep, river dividing a population of hummingbirds

Question 18

Despite inhabiting overlapping ranges, the western spotted skunk and the eastern spotted skunk do not interbreed, partly because the western species breeds in early fall and the eastern species breeds in late winter to early spring. This is an example of _____ isolation

Answer 18

Temporal

Question 19

Reproductive isolation

Answer 19

Increases with increasing genetic divergence

Question 20

Ernst Mary’s biological species concept says if you can’t interbreed then you are a different species, this includes physical, temporal, and location separations

Answer 20

True

Question 21

Consider meiosis, or the production of gametes. If a horse (2N=64) mated to a donkey (2N=62) they produce a sterile offspring, a mule. Mules are sterile because

Answer 21

Mules have 63 chromosomes and cannot produce viable eggs or sperm

Question 22

When does allopatric speciation occur?

Answer 22

When species are separated by a physical or geographic barrier

Question 23

The Founder Effect is defined as

Answer 23

When some members of a population cross and existing barrier and establish an isolated population

Question 24

Allopolyploids, more common in plants, are often fertile because each chromosome has a partner to pair with in meiosis

Answer 24

True

Question 25

Match the following characteristics and identify if they are associated with pre-zygotic or post-zygotic barriers

Answer 25

Habitat isolation and gametic isolation – pre-zygotic Reduced hybrid zygote viability and hybrid infertility – post-zygotic

Question 26

The Hadean is the time before life evolved

Answer 26

True

Question 27

Alfred Wegener and Marie Tharp suggested the idea of plate tectonics in 2021

Answer 27

False

Question 28

Match the type of plate movement with its definition

Answer 28

When two continental plates collide, they push up against one another, forming high mountain chains, such as the Himalayas – collision When continental plates diverge, new oceanic crust forms between them, resulting in deep rift valleys in which large freshwater lakes form – divergence Where oceanic and continental plates converge, the thinner oceanic plate is forced underneath the thicker continental plate – subduction

Question 29

Which sequence represents a correct chronological ordering of Earth's geological history, from the most ancient to the most recent period?

Answer 29

Cambrian, Devonian, Permian, Cretaceous

Question 30

Match the type of respiration with its characteristic

Answer 30

Occurs in the mitochondria of cells and uses oxygen – aerobic Early prokaryotes did this and produces less glucose per molecule - anaerobic

Question 31

Which finding was not known to nineteenth-century geologists?

Answer 31

Radioactivity can be used to determine the age of rocks

Question 32

If the half-life of a radioactive substance is 600 years, what fraction of the original material is left after 1,800 years?

Answer 32

One-eighth

Question 33

Which statement about continental drift is true?

Answer 33

Continents move because rising magma exerts tremendous pressure on the plates that float on top of it

Question 34

In the _____ period, fishes diversified and evolved jaws and club mosses , horsetails, and tree ferns became more common. The earlier fossil terrestrial vertebrate and insects date from this period and there was a mass extinction at the end of period that may have been caused by meteorite impacts.

Answer 34

Devonian

Question 35

The RNA world hypothesis states:

Answer 35

Life on Earth began with a simple RNA molecule that could copy itself without help from other molecules

Question 36

Organize the following statements into an orderly succession of the general path of early life took to evolve on our planet

Answer 36

1. Hot earth cooling organic elements present 2. Elements want to form into molecules 3. Miller and Urey demonstrated this 4. Lipids and fats can hold other macromolecules producing micelles 5. Self-replicating prokaryotic like cells 6. Great oxidation event 7. Lynn Margulis identified this theory 8. Single celled eukaryotic cells 9. Multicellular eukaryotic cells

Question 37

Stromatolites are famous for two key features that promote life on our planet. These are:

Answer 37

Producing oxygen and ozone

Question 38

The podcast question

Answer 38

Select all