BIOL 112 Exam 1 Flashcards
The binomial system assigns to each organism a unique name that describes its ____
Genus and Species
Which of the following conditions would allow gene frequencies to change by chance?
Small Population
The three domains of life are
Bacteria, Archaea, Eukarya
Which scientist proposed “Descent with modification”?
Charles Darwin
In _____, the fitness of a phenotype depends on how much common it is in the population.
Frequency dependent selection
Which of the following involves strengthening reproductive barriers so as to reduce the formation of unfit hybrids?
Stability
Which of the things below describes a phylogenetic tree that is rooted?
A tree that has a common ancestor to all organisms on that tree at the base
A defining characteristic of allopatric speciation is
Geographic Isolation
Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, which develop from similar embryonic tissues. These structures similarities are an example of ____
Homology
In a phylogenetic tree, when two lineages stem from the same branch point, they are _____.
Sister taxa
It has been observed that organisms on islands are different from, but closely related to, similar forms found on the nearest continent. This is taken as evidence that ____.
Island forms are descended from mainland forms
Which among the following leads to sympatric speciation?
Polyploidy
Which of the following mechanisms DOES NOT decrease genetic variance?
Diversifying Selection
Genetic Variation _____.
Must be present in a population before natural selection can act upon the population
The Linnaeus Classification system grouped organisms by ___.
Increasingly more specific groups
When individuals of one sex compete directly for mates of the opposite sex, it is known as ___.
Intrasexual selection
Which of the following is not an example of a prezygotic barrier?
Two species of insects produce infertile offspring
WHich of the following statements describes a mechanical isolation prezygotic barrier?
Two snails have shells that spiral in different directions
Which one of these processes describes bottleneck effect?
Sudden change in environments that alters gene frequency of a population
Which of the following scientific terms is used to describe a pattern of speciation that happens rapidly followed by a long period of stability?
Punctuated
Use the following tree to answer the question. Which tree depicts the same relationship?
A B C D-E. F-G.
G-F E-D. C B A
In a Hardy-Weinberg popultion with two alleles, A and a, that are in equilibrium, the frequency of allele a is 0.2. What is the frequency of individuals that are heterozygous for this allele?
a= .2
p= .8
2(.2)(.8)= .32
Given a population that contains genetic variation, what is the correct sequence of the following events under the influence of natural selection?
- Well adapted individuals leave more offspring than do poorly adapted individuals
- A change occurs in the environment
- Genetic frequencies within the population change
- Poorly adapted individuals have decreased survivorship
2->4->1->3
Arrange the following in order from most general to most specific
1. Natural Selection
2. Microevolution
3. Intrasexual Selection
4. Evolution
5. Sexual Selection
4, 2, 1, 5, 3
Which of the following is the most predictable outcome of increased gene flow between two populations?
Decreased genetic difference between the two populations
If natural selection favors an average phenotype, selecting against extreme variation, the population will undergo
Stabilizing Selection
The best classification system is that which closely ___
Reflects evolutionary history
Which of the following is the proper format of binomial nomenclature for the African Lion?
Panthera leo (italicized)
Butterfly allele frequency
0.3
Which of the following descriptions illustrates phenotype variation caused by environment?
Diet of caterpillars changes their morphology
Rank the following in order from most general to most specific
1.gametic isolation
2.reproductive isolation mechanism
3.sperm-egg incompatibility in sea urchins
4.prezygotic isolation mechanism
2,4,1,3
Which geologist proposed “gradualism”?
James Hutton
Microevolutions occur when
change in allele frequencies in a population occur over generations
The production of sterile mules by interbreeding between female horses (mares) and male donkeys (jacks) is an example of
Reduced hybrid fertility
Genetic Drift produces variation for evolution when ____
chance event causes allele frequencies to fluctuate unpredictably
Two species of frogs belonging to the same genus occasionally mate, but the embryos stop developing after a day and die. These two frogs species separate by ___
Reduced hybrid viability
Which of the follow describes this genetic grouping?
(D and E sister taxa, grouped with F connected but in different sister taxa) Paraphyletic
Whenever diploid populations are in HArdy-Weiberg equilibrium at a particular locus, __
The allele frequency should not change from one generation to the next
What are adaptations?
Inherited characteristics of organisms that enhance their survival
