Bio 2, Lecture Exam 1

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1

Which one of the following is not a fundamental assumption of Science?

A. that an objective reality (ie. realism) exists

B. that a consistency among facts exists

C. that empirical evidence is less important than logic

C. that empirical evidence is less important than logic

2

One of the ways in which science distinguishes itself from religion, mysticism and philosophy is:

A. science seeks to limit confirmation bias (strives for negation)

B. science seeks to promote confirmation bias

C. science seeks to ‘prove’ a hypotheses

D. science seeks to ‘prove’ theories

A. science seeks to limit confirmation bias (strives for negation)

3

Which one of the following definitions of the term 'natural' is implied in the definition of science as "the study of natural phenomena?"

A. natural = not man-made or not artificial

B. natural = typical or usual

C. natural = not metaphysical or not supernatural

C. natural = not metaphysical or not supernatural

4

According to scientists, what is the main difference between a theory and a law?

A. theories are well examined facts and laws are hypotheses that are explanatory

B. theories are natural and laws are not

C. theories are well examined hypotheses that explain phenomena and laws do not explain facts, they simply state them

D. theories are stated facts whereas laws are well examined hypotheses that explain phenomena

E. theories are just untested ideas and laws are facts

C. theories are well examined hypotheses that explain phenomena and laws do not explain facts, they simply state them

5

Suppose you sign up for a drug study and as part of the study you don’t know if the pills they have given you are the actual drug or a placebo. Suppose further that the nurse that gathers data from you doesn't know whether you have received the placebo or the drug. Which one of the following is a correct statement about this study?

A. it is a single blind study

B. it is a double blind study

C. it is a triple blind study

D. this study is non-blinded

B. it is a double blind study

6

New Lectures (weekly readings) are posted:

A. every Tuesday by 11:59pm

B. every Wednesday by 11:59pm

C. when I turn in my previous week's quiz

D. when I request it

E. every Monday by 11:59pm

E. every Monday by 11:59pm

7

You can take a quiz or turn in your answers to a quiz later than 2 minutes after its due date.

True
False

False

8

What should I do if:

I submitted my answers to an un-timed Quiz. The due date has not passed for that quiz and I wish to change my answers for that quiz. Think this one out - pick the most reasonable answer.

A. send changes to Holly's college email

B. send changes to Holly's phone as a text (preferable) or left on her personal voice mail

C. call the changes into the science department secretary

D. put the answers into Holly's SCC office mailbox (interoffice mailbox)

B. send changes to Holly's phone as a text (preferable) or left on her personal voice mail

9

The scheduled dates for Lecture Exams, Lab Practicals and the 2 timed Special Quizzes are found listed in the document 'Important Testing Dates and Protocols' posted in the Course Administration Module.

True
False

True

10

The Lecture Exam and Weekly Quiz questions are based on material presented in the Lectures.

True
False

True

11

Which one of the following most specifically defines natural selection?

A. Natural selection is the random survival and reproduction of individuals with typical genotypes.

B. Natural selection is the random survival and random reproduction of individuals with specific genotypes.

C. Natural selection is the non-random survival and reproduction of individuals with specific genotypes.

D. Natural selection is the random survival of random individuals.

E. Natural selection is defined exactly the same as concept of 'decent with modification'.

C. Natural selection is the non-random survival and reproduction of individuals with specific genotypes.

12

With Lepus americanus and Lepus californicus we see two species of hares (genus Lepus) that have lived in very different environments for a long time. The current range of L. americanus is Alaska and most of Canada, ranging south to northern California, northern New Mexico, northern Minnesota, northern Michigan, and in the east, southward through the Allegheny Mountains. L. californicus occurs all throughout Texas and into Mexico, ranging as far west as California and Baja California and north into Washington, Idaho, Colorado and Nebraska.

What is the scientific explanation for the differences between these two, similar, species?

A. They are different because one is a rabbit and the other is a hare.

B. They have always been different, that's just how things are.

C. Both kinds of rabbits were once members of the same species in the past, but by separation into different regions followed by different natural selection pressures they have adapted differently. They now look and act so differently that they do not mate with one another.

C. Both kinds of rabbits were once members of the same species in the past, but by separation into different regions followed by different natural selection pressures they have adapted differently. They now look and act so differently that they do not mate with one another.

13

Which one of the following statements does not pertain to the process of natural selection (ie. its not part of the definition nor of its parameters). Hint: one of the statements below is just false. Which one is it?

A. Heritable variation exists among the individuals of all kinds (e.g. species).

B. Not all offspring survive to reproductive maturity.

C. The strongest & most powerful individuals in populations always pass on their genes.

D. Survival of individuals is not random. It is based on the possession of attributes (ie. genotypes) that are most useful in creating a 'fit' between the individual and the environment. The degree of this 'fitness' is measured only as future reproductive success.

E. Over many generations, the accumulation and spread of many 'adaptive' (genotypes that increase the 'fitness' of individuals), heritable traits will change the frequency of those same adaptive traits along with numerous others, in a population and species. When a population and, therefore, species (ie. a particular 'kind'), undergoes this process, it will appear to be 're-molded' to a form better matched to the environment.

C. The strongest & most powerful individuals in populations always pass on their genes.

14

Which one of the following is not a factor affecting the gene frequencies of populations?

A. natural selection

B. genetic drift

C. gene flow

D. mutation

E. mating behavior

F. All of these are likely to affect the gene frequencies in a population.

F. All of these are likely to affect the gene frequencies in a population.

15

This is defined as the tendency for gene pools to change strictly by stochastic (randomly determined or chance) events.

A. genetic drift

B. gene flow

C. natural selection

D. fitness

E. phenotype

A. genetic drift

16

Gene flow is the population geneticist's code for ...

A. mutation

B. migration

C. natural selection

D. random mating

E. fertilization

B. migration

17

Most mutations are ...

A. gene flow

B. non-random

C. advantageous to the organism or the population to which it will contribute its genes.

D. disadvantageous to the organism or the population to which it will contribute its genes.

E. events that only create monsters.

D. disadvantageous to the organism or the population to which it will contribute its genes.

18

f the selections listed below, which one is the most likely cause of rapid evolutionary change?

A. natural selection

B. neutral mutations

C. chromosomal rearrangements

D. non-random mating

E. gene flow

C. chromosomal rearrangements

19

What term is defined as: 'when the fitness (advantage) of a specific trait is inversely proportional to its frequency in the population'?

A. natural selection

B. assortative mating

C. inbreeding

D. frequency-dependent selection

E. kin selection

D. frequency-dependent selection

20

Biologically speaking, the tendency for humans to mate with people within their same culture and socioeconomic group (not including relatives) is an example of...

A. assortative mating

B. genetic drift

C. kin selection

D. bigotry

E. frequency-dependent selection

A. assortative mating

21

What is the term for a cultural embodiment of the rational human tendency to seek natural explanations for observed phenomena? It represents an effort to understand the Universe using empirical methods.

Science

22

One of the two fundamental assumptions needed for science: The assumption that facts are real and not constructed by our perceptions. (also it is possible to accurately perceive reality)

Realism

23

One of the two fundamental assumptions needed for science: The assumption that natural phenomena are laws. (also Universal laws are sufficient to explain all phenomena)

Consistency

24

A well tested, highly respected, working explanation of basic natural phenomena. Explains the "how" of something

Theory

25

Term for a concept that is socially constructed by the human mind and is culturally and situationally relative

Value

26

Term for the human nature tendency to seek cororoboration, net negation

confirmation bias

27

An occurrence, circumstance, or fact that is perceptible by the senses

phenomenon

28

Name the three possible meanings of "natural" in order from the essay

1. Not artificial
2. Not uncommon
3. Not supernatural

29

Science comes form the Latin scire which means

to know

30

Science comes from the Indo-European root skei which means

to cut or split

31

The systematic identification, classification, and explanation of things and ideas and the relationships among them is called

descriptive science

32

Which form of natural does this statement refer to? The strange flashes or light seen in the swamp at night are clearly from natural causes.

3 Supernatural

33

Which meaning of the word natural is meant by the definition "Science is the study of natural phenomena"

3 Not supernatural

34

What activity can be considered the cornerstone of all science? How does it relate to the term science?

Classification. To classify is to cut or split objects into categories.

35

What are the 6 steps of the scientific method?

1. make observation
2. ask questions w.r.t. observations
3. form hypothesis(es)
4. make predictions that would follow if hypothesis is correct
5. verify prediction by either observation or experimentation
6. draw conclusions by analysis

36

Term for a postulated solution or working explanation of a problem that needs to be further tested

Hypothesis

37

Can you prove a hypothesis?

No! You can, however, currently accept a hypothesis as the best explanation or principle thus far examined.

38

Term for a sample to which the treatment is not applied but is subject to all other factors that the treated sample is exposed to

Control group

39

Term for a study wherein the participants and/or those taking information from the patients don't know who is receiving treatments

blinded study

40

Study in which those taking the info know who are in the treatment group but the patients do not

single blind study

41

Study in which those taking the info and the patients are both unaware of who is the the treatment group

double blind study

42

When an observation is made repeatedly in different systems and it is always the same under same conditions, the observation is called a ...

law
(defines the "what" of something)

43

Name the term for this statement: Because not all the individuals of a given kind will live to reproduce, probability favors the reproduction of those that have the characteristics or traits most advantageous for survival in their environment

natural selection

44

Name the term for this statement: The heritable change in allele frequencies in a population over time. The changes occur because of either natural selection, gene flow, genetic drift, or mutation

biological evolution (specific definition)

45

Name the term for this statement: the changes in the traits of populations within a species causes the populations to substantially diverge from one another possibly causing speciation. The changes can be caused by those listed above and also the processes of hybridization and endosymbiosis.

biological evolution (general definition)

46

Term for the study of gene frequencies in populations and how they are affected by selection, genetic drift, gene flow, mutation, and mating behavior

population genetics

47

Term for the tendency for gene pools to change strictly by stochastic (randomly determined) events

genetic drift

48

Genetic drift is most effective when the sample size is ...

small
1. (think flipping a coin all heads 4 times in a row vs. flipping 1000 times in a row)
2. (think the log falling on a population and destroying all the members with a certain allele)

49

Term for when an allele is unopposed in a population

fixed

50

Term for an effect that occurs when a segment of an existing population is separated from the main body of the population.

Founder effect
(this is an example of genetic drift due to the random nature of the event that set the sub population on such a journey)

51

Term for any catastrophic event that reduces the numbers of a population to very low levels also lending itself to genetic drift

genetic bottleneck
eg. natural disasters, hunting, habitat destruction

52

Term for migration either into or out of a population

gene flow

53

If there is low gene flow between two populations, what is likely to occur?

segregation
(the two populations become almost or completely isolated from one another)

54

Complete isolation of a population may lead quickly to...

speciation

55

A change in an organism's DNA is called

a mutation

56

Are mutations random with respect to chromosomes?

No, there are placed on the chromosomes that are more likely to mutate than others.

57

Are mutations random with respect to natural selection?

Yes they are random. Natural selection cannot direct mutation.

58

Most mutations cause...

loss of function of the mutated gene and are disadvantageous.

59

In rare instances, a mutation's loss of function is...

advantageous

60

Mutations that cause a loss of function are the origin of...

recessive alleles

61

Molecular clocks can you what to determine the origin of a species and larger taxonomic groups?

neutral mutations

62

"Instant" species change can occur from what

mutations of whole chromosomes. (rearrangements with regard to their constitution and number)

63

Type of mating behavior where individuals mate with others that are closely related. If widespread this quickly reduces genetic varitation.

Inbreeding. (ultimate height of inbreeding is selfing or self fertilization)

64

Inbreeding reduces BLANK and promotes BLANK

reduces heterozygosity
promotes homozygosity

65

Type of mating behavior where individuals select mates based on their characteristics. (Those that have appealing characteristics are chosen more often as mates)

Assortive mating

66

Type of selection that when a trait is rare, it is favored by selection and when it is common it is at a disadvantage.

Frequency-dependent selection

67

Type of selection that is the altruistic behavior of an organism that may benefit relatives and thereby increase its and its relatives' survival.

Kin selection

68

Type of selection in which there are differential abilities of individuals to acquire mates in competition with other individuals of the same sex and this directly leads to the change in allele frequencies over time.

Sexual selection

Can be based on morphological, biochemical, or behavioral traits.

Can also be improved opposite sex preference

69

Sexual selection often leads to BLANK.

The differences between the secondary sex characteristics of males and females.

Sexual dimorphism

70

(Support of evolution)
The study of the geographical and habitat distributions of organisms and the historical and biological factors which produced them

biogeography

71

Why don't multiple islands have identical species as related to biogeography?

island species came from mainland populations that migrated the the island and that they genetically diverged from their ancestors on the mainland.

72

(Support of evolution)
Device used to determine species to be related based on fossil evidence. Often times showing transitional forms.

Fossil record
(Transitional forms may not exist in events of chromosomal mutations)

73

(Support of evolution)
Comparison of morphology between taxa.

comparitive anatomy

74

Body parts of differing species that due to ancestry have similarity of structure but not always function

Homologous structures

75

Organs or structures that completely lack function in an organism but not in the organism's ancestors.

vestigial organs

76

(Support of evolution)
Comparing the tissues of different animals as they develop is called...

Comparative Embryology

77

What have comparative embryologists noted?

Certain taxa go through very similar stages of development. (Vertebrates have a gill pouch stage whether or not they ultimately develop gills)

78

All the genes that have to be turned on to complete the formation of some body part

developmental cascade

79

Distantly related species share similar basic body plan development because of these two things

1. shared master developmental genes
2. shared developmental cascades

80

Study of molecular genetics, embryology and evolution has led to a new hybrid discipline of biology called

evolutionary developmental biology
evo-devo

81

(support of evolution)
Division of science that makes note of the conservation of certain genes and/or gene segments and the proteins that they produce across distant taxa

molecular biology

82

DNA segments within larger genes that turn on or off other genes during development and are found in numerous related taxa. They are conserved sequences across taxa.

Homeobox genes.
(All Homeobox genes are developmental genes but not all developmental genes are homeobox genes)

83

Homeobox gene that when turned on by another upstream gene creates "spots". The spots produce outward projections called limbs.

distal-less

84

a particular genotype is measured by how much it spreads in the next generation relative to another genotype. Purely based on offspring produced. This is called...

relative fitness

85

The differences in or between populations of a species.

Variation

86

If there is more than one phenotype for a trait, then the trait is...

polymorphic

87

If there is only one phenotype for a trait in a population or species, then that trait is...

monomorphic

88

Term that describes the concept that most traits are produced from multiple genes

polygenic inheritance

89

Type of selection that occurs when conditions favor individuals exhibiting one extreme of a phenotype range, thereby shifting a population's frequency curve for the phenotypic character in one direction or the other. Common when the environment changes.

Directional Selection

90

Type of selection where the mean doesn't shift but increases in frequency. The frequency of the extreme frequencies are reduced.

Stabilizing Selection

91

Type of selection that favors the extreme phenotypes. The mean stays the same but the number of individuals at the mean decrease.

Disruptive Selection

92

Definition 1: A BLANK can be defined based on its reproductive isolation

species
(problem is some species do make viable offspring, ie. hybridize)

93

Definition 2: A BLANK can be defined based on its phenotypes or morphology

species
(more accepted, but where to draw the morphological separation is not always clear)

94

Definition 3: A BLANK is a group of actually or potentially interbreeding populations that are generally reproductively isolated from other such groups.

species
(best definition)

95

Four ways speciation can come about

1. accumulation of many gene changes
2. small number of gene changes that have occured to developmental genes
3. hybridization (mating between species)
4. endosymbiosis (acquisition of a genome by a host

96

The physical splitting of one genome into two via geographic barriers and then the accumulation of mutations in the 2 separate groups producing speciation.

allopatric speciation

97

One genome can split into two via a reproductive barrier that is not caused by geographic separation in a process called

sympatric speciation
(could be due to timing such as early bloomers)
or
(could be due to chromosome number)

98

Term for when a species increases its chromosome sets and there is now variation in chromosome sets

autopolyploidy
(a form of sympatric speciation)

99

Term for an increase in chromosome number that has been preceded by hybridization

allopolyploidy
(a form of sympatric speciation)

100

Sympatric speciation can occur via these three ways...

1. reproductive barriers forming, via mutations that allow some individuals to diverge from the populations genome.

2. autopolyploidy

3. allopolyploidy

101

If a small number of mutations occur to developmental genes, that can cause...

speciation

102

Retaining juvenile traits but having sexual maturity is called...

neoteny

103

When two separate species successfully make offspring (hybridize), that causes...

speciation

104

Hybridization occurs most often in what two situations?

Where pollen is spread by the wind
Where gametes are let loose in water

105

The close, intimate (on or inside another) association between 2 different species of organisms.

Symbiosis

106

Smaller body in symbiosis that lives on or in the larger is called the

Symbiont

(The larger body is the host)

107

Symbioses in which the symbiont lives upon the internal or external body surfaces of the host is called

ectosymbiosis

108

Symbioses in which the symbiont lives inside the host cells and is called

endosymbiosis

109

What are the three organelles thought to have endosymbiont origins?

1. mitochondria
2. plastids
3. kinetosomes

110

What are the three pieces of evidence to support the endosymbiont theory?

1. Mitochondria and Plastids have a double membrane
2. Have their own DNA
3. Mitochondria and Plastids have their own ribosomes

111

Species 1 has a population that is rather small (8 individuals). In this population there are only 2 individuals that are ‘Aa’ and 6 are ‘AA’. Suppose further, that by chance, the 2 ‘Aa’ don’t mate with each other and instead they mate with the AA individuals. Question: What is the chance that an Aa individual crossed to a AA individual could make AA offspring? [note: don't over-think; this is a simple genetics cross; gets more difficult in following questions]

A. 0%

B. 25%

C. 50%

D. 75%

E. 100%

C. 50%

112

Species 1 has a population that is rather small (8 individuals). In this population there are only 2 individuals that are ‘Aa’ and 6 are ‘AA’. Suppose further, that by chance, the 2 ‘Aa’ don’t mate with each other and instead they each mate, only one time each, with an AA individual. [O.K. this is really a continuation of #1 above]
Let's next, suppose that the 2 separate AaxAA crosses produced only AA offspring and the parents died after this single mating. Also, the AA parents mated once to each other and died after the mating. Thus, the ‘a’ allele is lost this population. The loss of the ‘a’ allele, under these circumstances, in this population and the subsequent population having only A, has come about because of :
[i.e. what term, out of the selections below, best describes a mechanism whereby the population is now 'fixed' at dominant alllele ('A') for the A trait.]

a synopsis for this problem:
Aa x AA = 1 offspring that is AA;
Aa x AA = 1 offspring that is AA;
all others are AA x AA = all AA offspring
A. gene flow

B. genetic drift

C. frequency dependent selection

D. inbreeding

E. assortative mating

F. directional selection

G. stabilizing selection

H. disruptive (diversifying) selection

I. kin selection

J. sexual selection

B. genetic drift

113

Species 2 has a population that is rather small (10 individuals). In this population there are only 2 individuals that are ‘aa’ and 8 are ‘AA’. Suppose further, the 2 ‘aa’ perish in a hurricane before ever getting a chance mate. The loss of the ‘a’ allele in this population has come about because of:

A. gene flow

B. genetic drift

C. frequency dependent selection

D. inbreeding

E. assortative mating

F. directional selection

G. stabilizing selection

H. disruptive (diversifying) selection

I. kin selection

J. sexual selection

B. genetic drift

114

Suppose a population of: AA, Aa, aa individuals each with their own separate phenotype (i.e. 3 phenotypes total).
Question: Suppose that the ‘aa’ individuals were more cold tolerant and left more offspring than the other genotypes. In a cold environment, would you expect the relative fitness of ‘aa’ individuals to be higher or lower than the others genotypes?

A. higher

B. lower

A. higher

115

The scenario detailed in previous question is indicative of:

A. gene flow for cold tolerance

B. genetic drift for cold tolerance

C. natural selection for cold tolerance

D. evo-devo for cold tolerance

E. assortative mating for cold tolerance

C. natural selection for cold tolerance

116

Suppose a population wherein males have a green necks. Recently, those males that have darker green necks are more often chosen by females (always drab light brown) for mating. Those males with lighter green necks are chosen less often. Question: females CHOOSING and MATING with (both behaviours) males with darker green colored necks is an example of:
A. gene flow

B. genetic drift

C. frequency dependent selection

D. inbreeding

E. assortative mating

F. directional selection

G. stabilizing selection

H. disruptive (diversifying) selection

I. kin selection

E. assortative mating

117

Suppose a population of an species wherein the males have a green necks. Recently, those males that have darker green necks are more often chosen by females for mating. Those with lighter green necks are chosen less often for mating. Additionally, all male offspring, produced from the matings of females with dark green necked males, have dark green necks. [note: this is same background as previous question]

If females continue mating disproportionately with dark necked males, the dark neck phenotype will increase in frequency in the population. The TYPE of selection that would be increasing dark green necked individuals in this population would be correctly termed:

A. gene flow

B. genetic drift

C. frequency dependent selection

D. inbreeding

E. assortative mating

F. directional selection

G. stabilizing selection

H. disruptive (diversifying) selection

I. kin selection

J. sexual selection

J. sexual selection

118

Suppose a population of an species wherein the males have a green necks. Recently, those males that have darker green necks are more often chosen by females for mating. Those with lighter green necks are chosen less often for mating. Additionally, all male offspring, produced from the matings of females with dark green necked males, have dark green necks. [note: this is same background as previous question]

If females continue mating disproportionately with dark necked males, the dark neck phenotype will increase in the population. The MODE of selection that would be increasing dark green necked individuals in this population would be correctly termed:

A. gene flow

B. genetic drift

C. frequency dependent selection

D. inbreeding

E. assortative mating

F. directional selection

G. stabilizing selection

H. disruptive (diversifying) selection

I. kin selection

J. sexual selection

F. directional selection

119

What term is defined as ‘a group of actually or potentially interbreeding populations that are generally reproductively isolated from other such groups’?

A. neoteny

B. species

C. population

D. sympatry

E. allopatry

F. autopolyploidy

G. allopolyploidy

B. species

120

The limitation of (or problem with) the Biological Species concept is:

A. doesn’t allow for sympatry

B. doesn’t allow for drift

C. doesn’t allow for drift

D. doesn’t allow for reproductive barriers

E. doesn’t allow hybridization

E. doesn’t allow hybridization

121

As listed in this week’s lecture, which one of the following cannot produce speciation?

A. neutral mutations

B. a few mutations of developmental genes

C. many mutations of non-developmental genes

D. endosymbiosis

E. hybridization

A. neutral mutations

122

Suppose a population that covers an area of 1 square mile. Next suppose that a major highway is put right through the center of the population dividing it into 2 populations that, although doing well, can no longer mate with each other. If over time, the 2 separated populations accumulate enough phenotypic differences to be considered 2 species, what type of speciation would this be called?

A. hybridization

B. symbiosis

C. sympatric speciation

D. allopatric speciation

E. b & c

D. allopatric speciation

123

If a species increases its chromosome sets so that there is now variation in chromosome sets without hybridization directly preceding it, it is called:

A. allopatry

B. neoteny

C. ploidy

D. allopolyploidy

E. autopolyploidy

E. autopolyploidy

124

When individuals from two different species successfully make offspring it is called:

A. disruptive selection

B. allopatry

C. neoteny

D. genetic drift

E. hybridization

E. hybridization

125

Which one of the following will not produce sympatric speciation?

A. reproductive barriers forming (from mutation) that allow some individuals to diverge from the rest of the population’s genome

B. autopolyploidy

C. hybridization

D. allopolyploidy

C. hybridization

126

What are the 3 organelles thought to have an endosymbiont origin?

A. mitochondria, plastids, and kinetosomes

B. ribosomes, golgi , and nucleus

C. ribosomes, cell membrane, and plastids

D. mitochondria, golgi, nucleus

E. stroma, endoplasmic reticulum and golgi

A. mitochondria, plastids, and kinetosomes

127

Which one of the following is not evidence* in support of the endosymbiont theory?

* note that a statement may be true but, it is not evidentiary (i.e not evidence) if it doesn't support or lend credence to the idea it is linked to. For example, the fact that I have brown hair is not evidence in support of the statement (ie. evidentiary) that I am a female. The statement is true but, it doesn't support the contention that I am female.

A. mitochondria have their own DNA (small, looped)

B. chloroplasts have photopigments

C. chloroplasts and eukaryotic flagella have their own DNA (small, looped)

D. chloroplasts have their own ribosomes (which resemble bacterial ribosomes)

E. mitochondria have their own ribosomes (which resemble bacterial ribosomes)

B. chloroplasts have photopigments