Evolution Unit Flashcards
Which of the following would best explain why we use the phrase “Theory of Evolution” instead of the “Hypothesis of Evolution”?
A. It is based on evidence and not an educated guess
B. It is a broad explanation for many observations
C. It may be tested
D. All of the above are correct
D. all of the above are correct
Which of the following is NOT a characteristic of natural selection?
A. More offspring are born than will survive to reproduce
B. Breeding pairs are chosen by humans
C. Organisms that are better adapted are more likely to survive
D. Mutations appear randomly
B. breeding pairs are chosen by humans
* this answer deals with Artificial Selection not Natural Selection
The diagram below demonstrates the Law of Superposition.
WHEN LOOKING AT THIS DIAGRAM, WHICH STATEMENT WOULD BE TRUE
A. Layer A is the oldest and Layer B is the most recent
B. Layer A is the same age as Layer B
C. Layer A is the most recent and Layer B is the oldest
D. You can’t tell which layer is the oldest based on this diagram, we would need dates to determine
C. Layer A is the most recent and Layer B is the oldest
this is because A is on top and B is on the bottom
Based on his Theory of Evolution, which statement would Darwin disagree with?
A. Individuals best suited to their environment survive and reproduce most successfully
B. Diverse species evolved from common ancestors
C. Organisms produce more offspring than can survive
D. Individual organisms differ, but none of this is inherited
E. Organisms compete for limited resources
D. Individual organisms differ, but none of this is inherited
Darwin would diagree because according to his Theory of Evolution, only traits that are inherited may be passes on (acquired traits are not).
Which statement would best support the fossil data and Darwin’s theory of evolution?
A. Comparing fossils from different layers would not support Darwin’s theory of evolution
B. The number of different species on the bottom would be greater than the number of species in the top layer
C. Organisms on the bottom layered would be more complex
D. Fossils found on the bottom layer would have evolved from fossils on the top layer
E. Comparing a fossil from the top layer to one on the bottom would show how an organism may have evolved.
E.Comparing a fossil from the top layer to one on the bottom would show how an organism may have evolved
This diagram represents which cause for evolutionary change?
Founder Effect which causes genetic drift
An inherited characteristic that increases an organism’s ability to survive and reproduce in its specific environment is called a/an ________________.
Adaptation
A population of squirrels is divided by a river and a canyon. Over time, the squirrels evolve into 2 separate colors and are unable to mate with one another. This is an example of ___________.
Geographical Isolation
This image represents what type of structure that is used to support the Theory of Evolution?
homologous
* similar structures - in this case the bones of the forelimb are similar in comparison of these organisms
Although they may be different in function
Use to support that they share a common ancestor
What feature on the finch did Darwin study and use as part of his evidence that evolution occurred?
Beaks
One common ancestor, but each population on separate islands had evolved due to different food sources available.
We also saw with the Gizmo how rainfall may help in selected certain size beaks.
Name 4 different types of evidence used to support the Theory of Evolution
- DNA sequences - compare and see % similar (see the ad for 23andme - a company that does DNA tests- this was really on the internet!)
- Homologous structures - compare parts of the anatomy and see what parts are similar (homologous would be similar in structure - but may be different in function)
- Vestigial structures - structures like the human appendix or wisdom teeth or a whale’s hip bone
they are greatly reduced from the original ancestral form and are no longer functional or is of reduced or altered function
- Embryos - compare development of embryos
- Fossils - serve as a representation of ancestors and record of previous life/organism (transitional fossils)
The concept that each living species has descended, with changes, from other species over time is referred to as _________________________.
descent with modification
A farmer’s use of the best livestock for breeding OR a dog breeder breeding only chocolate colored New Foundlands is an example of ________________________.
Artificial Selection
A random change in a a small populuation’s allele frequency is known as ____________.
Genetic Drift
Which of the following is an important concept in Darwin’s theory of evolution by natural selection?
I. Struggle for Existence
II. Survival of the Fittest
III. Descent with modification
* You can pick none, just 1 of the answers, only 2 of the answers, or all three!
if you picked all 3 you are correct!
Based on the table, which 2 organisms are most closely related?
dolphin & killer whale
because they have same Kingdom, Phylum, Class, Order, Family
- they only differ at the Genus and Species level
Human would be the next closest related organism (share same class)
Giant Kelp least closely related because not even in same Kingdom
This image would represent what kind of structure used in studying Evolution
Analogous Structure - a physical structure, present in multiple species, that is similar in FUNCTION but different in FORM AND INHERITANCE
* THESE ORGANISMS ARE LESS CLOSELY RELATED
* NOTE THE DIFFERENCE BETWEEN THIS & HOMOLOGOUS STRUCTURES - which is similar in Structure/form and inheritance BUT not in FUNCTION (ex. forelimb of human, whale, bird, and dog)
Use the circle graphs to answer the question.
The graphs illustrate change in a lizard population over time. Which process most likely led to the change in the lizard population?
A. natural selection acting on a harmful trait
B. natural selection acting on a beneficial trait
C. natural selection acting on a dominant trait
D. natural selection acting on a recessive trait
Correct Answer A. natural selection acting on a harmful trait.
This is another tricky question straight from the Keystone Sample! Technically, you don’t need the graph - it is to distract you!
* It can’t be C or D because natural selection can only act DIRECTLY on a trait (phenotype) NOT A GENOTYPE
- it INDIRECTLY causes a change in the genotype due to what phenotypes die/survive
* It can’t be B because it refers to a beneficial trait and natural selection acts on the ones that die due to a negative trait
Use the illustration to answer the question.
The skeletons of mammalian forelimbs represent variations of a structure that was present in their common acestor. What has most likely caused the variation in forelimbs?
A. changes in muscle structure
B. changes in genetic codes
C. trait formation due to behaviors
D. Development of vestigial structures
Correct answer is B. changes in genetic codes
Another tricky question from Keystone Sample!
This image shows homologous structures (same parts but DIFFERENT functions). So they have a common ancestor and have change over time. This would have to be due to genetics - only way to pass on a trait is if it is inherited.
This is also a good example of DIVERGENT evolution - the way that homologous structures show variation. see image!
A, C - wrong because wouldn’t be passed on
D - vestigial structures are nonfunctioning or low functioning and these are structures they still use.
Use the table to compare the genes for the Rat to the mouse and the cow.
Which organism is more closely related to the RAT?
The RAT and the MOUSE are more closely related!
Note that this table is showing DIFFERENCES Between them. So the lower the number the more alike they are!
** WATCH OUT & READ CAREFULLY ON THE EXAM!
You could also see a table where they show you SIMILARITIES AND THEN IT WOULD THE HIGHER THE NUMBER THE MORE CLOSELY RELATED!
A group of students measured a ten-square-meter section of a pond ecosystem and recorded observations. Which statement is a testable hypothesis?
A. the frogs living in the pond represent a population.
B. water is an abiotic component in the pond ecosystem
C. If the fish are given more food, then they will be happier
D. If the frogs are startled, then they will jump into the water.
Correct answer is D. If the frogs are startled, then they will jump into the water.
* can see from the table we know how many frogs there are and can count how many will jump
Clues for questions about Hypothesis:
“if” … “then” and Can measure the results
A & B aren’t questions that need an experiment to answer/ already can answer
C. can’t measure if they are happy- can’t ask the fish “are you happy”
What type of selection does this show?
Directional- shifts toward 1 end
Image here shows the 3 types - compare generation 1 to generation 2 to see what happens in each type
Which diagram represents convergent evolution?
A B or C?
correct answer: B!
convergent means 2 separate species evolve similar traits separately from one another - did NOT share a common ancestor
A & C wrong because…
A is showing divergent evolution - start with common ancestor but diversify
C is showing parallel evolution - share common ancestor and later evolve similar traits separately from one another
Use the graph to answer the question.
Tail length in mice varies within a population. Scientists observed change in the distribution of tail lengths in a mouse population over time. At the genetic level, what has most likely happened to the allele for the shortest tail lenghts?
A. the allele changed from being dominant to being recessive.
B. the allele changed from being autosomal to being sex-linked.
C. the allele became less frequent than the allels for longer tail lenghts
D. the allele began to code for long tail lenghts instead of the shortest ones.
CORRECT ANSWER IS C!
