Unit 1 Review: Textbook Questions

Question 1

What would have happened if Pasteur had tipped one of his flasks so that the broth in the flask came into contact with the curve of the neck? Explain how this result would or would not have supported his conclusion.

Answer 1

If Pasteur had tipped his flask so that the broth inside had come in contact with the microorganisms trapped in the curve of the neck, the broth would have been contaminated and microorganisms would have grown in the flask. This would have supported Pasteur’s conclusion that microorganisms came not from the air, but from other microorganisms.

Question 2

Difference between spontaneous generation and biogenesis

Answer 2

Spontaneous Generation says that living things could arise from nonliving things in a process called spontaneous generation. Biogenesis states that all living things come from other living things.

Question 3

in the 17th/18th century, spontaneous generation was used to explain how

Answer 3

new life started

Question 4

Redi’s experiment was important because it showed that

Answer 4

flies do not form from rotting meat

Question 5

People objected to Spallanzani’s experiment because

Answer 5

he boiled his flasks for a long time.

Question 6

The neck of Pasteur’s flask

Answer 6

allowed air to enter the flask but kept particles out.

Question 7

During the first half billion years of it’s existence, Earth and the solar system grew by a process involving

Answer 7

collisions with space debris

Question 8

The oldest fossil of cellular life found on Earth is about

Answer 8

3.5 billion years old

Question 9

Coacervates and microspheres cannot evolve because they have no

Answer 9

Genetic information

Question 10

Miller and Urey’s experiment provided

Answer 10

support for Oparin’s hypothesis about the origin of organic molecules

Question 11

Coacervates and microspheres are collections of

Answer 11

collections of organic molecules enclosed within a boundary.

Question 12

The generation of organisms from nonliving material does not occur today mostly because

Answer 12

there is not enough energy to drive the chemical reactions needed to form the complex compounds necessary for life.

Question 13

What is the difference between an acquired trait and a genetic trait?

Answer 13

An acquired trait is not determined by genes and arises during an organisms lifetime and isn’t usually passed down to offspring. Ex: tattoo
A genetic trait is determined by genes and passed down to offspring.

Question 14

Distinguish between homologous structures and analogous structures.

Answer 14

Homologous structures - same structure (due to shared ancestor), but different function. (ex) bet wing and human hand
Analagous - different structure, same function (ex) insect wing and bird wing

Analogous structures: features serve identical functions, and look somewhat alike. They have very different embryological development, however, and may be very different in internal anatomy.
Ex: Hummingbird and humming moth. Both can hover to feed on sugar-rich nectar from flowers. But, there is no anatomical or embryological similarity between their wings. Birds and insects differ greatly in anatomy and embryological development. Although they share a very remote ancestor, their wings evolved independently and differently in more recent ancestors of each animal.

Homologous structures: similar features that originated in a shared ancestor. Homologous features can result from modifications that change an original feature to two different types, such as a wing and an arm.
Ex: The forelimbs of the penguin, alligator, bat, and human all derive from the same embryological structures. Although they look different and vary in function, they have very similar skeletal structures, and derive from the same structures in the embryo.

Question 15

How are divergent evolution and adaptive radiation related?

Answer 15

Adaptive radiation is a kind of divergent evolution in which many related species evolve from a single ancestral species.

Question 16

Lamarck’s explanation for the modification of a species depended on

Answer 16

inheritance of acquired features.

Question 17

The idea that processes occuring now on Earth are much the same as those that occurred long ago is called

Answer 17

uniformitarianism

Question 18

The observation that organisms arise in locations where similar, extinct organisms lived is referred to as

Answer 18

biogeography

Question 19

Similarities in Galapagos finches implied

Answer 19

adaptive radiation

Question 20

Difference in reproductive success is

Answer 20

natural selection

Question 21

Great similarity between species implies

Answer 21

recent common ancestry

Question 22

Features that were useful in ancestors but are no longer useful are called

Answer 22

vestigial structures

Question 23

Similar features in different species that originated in a shared ancestor are called

Answer 23

homologous features

Question 24

A hummingbird and hummingmoth have a number of superficial features in common with each other. This is an example of

Answer 24

convergent evolution

Question 25

The phylogenetic tree on pg 294 implies that modern finches and armadillos

Answer 25

share a remote common ancestor

Question 26

How was Darwins theory of evolution different from Lamarcks?

Answer 26

Darwin state that species change because individuals differ and that those with more favorable traits reproduce more, increasing those traits in a population.
Lamarck argued that a single organism could change in response to its environment and pass that change on to its offspring.

Question 27

Why are some traits favorable for some species and not others?

Answer 27

The traits that are favorable for a particular species are influenced by the environment. A white coat may be helpful in a snowy environment, but might not be favorable in a tropical rain forest.

Question 28

Could a characteristic that is not controlled by genetics be selected by the environment? Would this characteristic contribute to the evolution of the organism that has it?

Answer 28

Yes. a non genetic trait could be selected by the environment but it would NOT contribute to evolution bc it wouldn’t be passed down to offspring.

Question 29

In recent years, paleontologists have claimed that in some cases the evolution of a new species occurs quite suddenly—in less than a thousand years. Darwin stated that evolution was a gradual process. What effect does generation time have on evolution rate?

Answer 29

Organisms with a short generation time (like prokaryotes) could be modified more rapidly than those with a long generation time. A bacterium with a gene ration time of 1 hour would have almost 9 million generations in 1,000 years - whereas humans would only have 40 generations in that same period. More generations= more variation= more chance of natural selection + eventually evolution

Question 30

The process of natural selection throughout the history of life on Earth has resulted in the success of some species and the extinction of other species. Why has natural selection not resulted in the existence of a single best-adapted species?

Answer 30

There are many diff environments and many diff demands on species. A species adapted to 1 environment might fare poorly in a diff environment. Diff types of orgaisms are interrelated in complex ways. Ex: animals depend on plants for their existence and plants depend on animals that feed on them for pollination.

Question 31

What is the relationship between natural selection and sexual selection?

Answer 31

Sexual selection is a form of natural selection whose driving force is success at attracting mates

Question 32

What is the relationship between evolution and natural selection?

Answer 32

Natural selection is the primary driving force for evolution. Variation -> natural selection-> evolution

Question 33

Freeways may provide an effective geographic isolating mechanism for some slow-moving animals. Why are such artificial barriers not likely to result in complete speciation?

Answer 33

Such artificial barriers are unlikely to be in place long enough for speciation to occur

Question 34

The most common definition of species states that a species is a group of organisms that can interbreed and produce fertile offspring in nature. A mule is a sterile offspring of a horse and a donkey. By the definition above, do a horse and a donkey belong to the same species? Explain your answer

Answer 34

A donkey and a horse belong to different species because their mating does not produce fertile offspring.