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8 Feb 2018

1. What advantages and disadvantages were encountered by the first plants to venture out onto land? Give a few examples of plant adaptations to life on land.

2. Using an example of a familiar plant, describe its life cycle as it alternates between multicellular sporophyte and gametophyte stages. Describe these multicellular stages and explain where fertilization, mitosis, and meiosis occur in the life cycle.

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Casey DurganLv2

8 Feb 2018

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Related questions

Question 1

The key innovation that allowed for plant survival on land, seenin the first land plants and all others after, but not in thecharophytes, is

Question 1 options:

	fruit.
	vascular tissue.
	the seed.
	protection of the embryo.

Question 2

Which dramatic change in the alternation-of-generations lifecycle led to the protection of all phases of the life cycle and theformation of seeds?

Question 2 options:

	transition from a dominant gametophyte generation to a dominantsporophyte generation
	transition from a dominant sporophyte generation to a dominantgametophyte generation

Question 3

Which structure(s) allow the sporophyte of vascular plants to beprotected against drying out?

Question 3 options:

	the waxy covering of leaves, called the cuticle
	small openings in the leaves, called stomata
	guard cells that surround each stoma
	all of these structures protect the dominant sporophyte fromdrying out

Question 4

Why are the bryophytes called nonvascular plants?

Question 4 options:

	because they are specialized for transporting water and organicnutrients
	because their roots, stems, and leaves lack vascular tissue
	because they protect their embryo
	because they produce wind-blown spores

Question 5

Which generation is dominant in the bryophytes?

Question 5 options:

	the generations are equally dominant
	the sporophyte
	the gametophyte
	there is no sporophyte generation in bryophytes

Question 6

Which of the bryophytes are typically low-lying, due mostly totheir need for moisture and lack of vascular tissue?

Question 6 options:

	the mosses
	the liverworts
	the hornworts
	all of the bryophytes are low-lying

Question 7

Which structure of the moss protects the embryo from dryingout?

Question 7 options:

	the archegonium
	the antheridium
	the sporangium
	the stalk

Question 8

Cooksonia were the first __________ plants; they hadwind-blown spores, __________, leaves, and roots.

Question 8 options:

	nonvascular; branches
	vascular; seeds
	nonvascular; seeds
	vascular; branches

Question 9

The roots of today's lycophytes are much like __________ were inearly vascular plants; the vascular tissue is __________.

Question 9 options:

	roots; centrally placed
	stems; centrally placed
	leaves; only found at the perimeter
	branches; only found at the perimeter

Question 10

Pteridophytes, or ferns and their allies, are __________vascular plants with __________.

Question 10 options:

	seed-producing; microphylls
	seedless; microphylls
	seedless; megaphylls
	seed-producing; megaphylls

Question 11

Microphylls __________. Megaphylls__________.

Question 11 options:

	are found in all vascular plants; are only found in thelycophytes
	are broad leaves with a single strand of vascular tissue; arenarrow and have several strands vascular tissue
	are broad leaves with several strands of vascular tissue; arenarrow and have a single strand of vascular tissue
	are narrow and have a single strand of vascular tissue; arebroad leaves with several strands of vascular tissue

Question 12

The fern life cycle

Question 12 options:

	all of these choices accurately describe the fern lifecycle.
	is dependent on external water.
	relies on the wind to disperse the spores.
	produces a gametophyte that lacks vascular tissue.

Question 13

Seed plants use meiosis to produce

Question 13 options:

	spores and pollen.
	seeds and fruit.
	pollen and seeds.
	microspores and megaspores.

Question 14

In seed plants, a microspore develops into

Question 14 options:

	an egg.
	a pollen grain.
	a sporophyte.
	All of these answers correctly complete this sentence.

Question 15

Within the angiosperms, or ___________, two groups exist. Theyare named for their __________.

Question 15 options:

	vascular plants; number of cotyledons, or seed coats
	nonvascular plants; leaf type
	flowering plants; number of cotyledons, or seed coats
	fungi; leaf type

Question 16

The __________ parts of a flower are the stamens, each of whichhas two parts: the anther and the filament. The __________ parts ofa flower are the carpel, which has three major regions: the stigma,the style, and the __________.

Question 16 options:

	female; male; ovary
	male; female; sepals
	female; male; sepals
	male; female; ovary

Question 17

Double fertilization during the angiosperm life cycle involvestwo sperm, one of which __________, while the other __________.

Question 17 options:

	fertilizes the egg to form a zygote; produces the endospermnucleus, which will develop into food for the developing plant
	is a mature male gametophyte; is an immature malegametophyte
	lands on the carpel of the plant; is usually blown away in thewind
	develops into the seed; develops into the fruit that surroundsthe seeds

Question 18

The bodies of most fungi are made up of a network of filamentscalled hyphae.

Question 18 options:

	True
	False

Question 19

What is the difference between land fungi and the chytrids?

Question 19 options:

	Land fungi are motile and have flagella at all stages of theirlife cycle. The chytrids do not have flagella.
	Land fungi are nonmotile and do not have flagella at any stageof their life cycle. The chytrids have flagellated spores andgametes.
	Land fungi are nonmotile and only have flagellated spores. Thechytrids have flagellated spores and gametes.
	Both are motile for part of their life cycle. Land fungi aremotile as gametes. Chytrids are motile as spores.

Question 20

The vast majority of described species of fungi are __________fungi, which include unicellular __________, which reproducesexually once their food supply runs out. When yeast ferment, theyproduce ethanol and carbon dioxide.

Question 20 options:

	zygospore; black bread molds
	club; mushroom
	sac; yeast
	mutualistic; lichen

yellowmuskrat453

Question 1

The process by which RNA is synthesized using DNA as a template is â¦

Select one:

a. replication

b. transcription

c. translation

d. inspiration

Question 2

Which of the following occurs during meiosis but not mitosis?

Select one:

a. DNA condenses into chromosomes

b. nuclear envelop disappears

c. homologous chromosomes separate

d. sister chromatids separate

Question 3

Which part of the animal life cycle is haploid?

Select one:

a. gamete

b. zygote

c. sporophyte

d. spore

Question 4

Single celled eukaryotic organisms are â¦

Select one:

a. viruses

b. bacterial

c. archaea

d. protists

Question 5

Which type of cellular division results in the formation of diploid cells from a diploid parent cell?

Select one:

a. mitosis

b. meiosis

c. interphase

d. A and B but not C

e. all of the above

Question 6

A sequence of DNA that codes for a single protein is a â¦

Select one:

a. gene

b. ribosome

c. mRNA

d. none of the above

Question 7

Which of the following is characteristic of animals?

Select one:

a. heterotrophic

b. sexual reproduction

c. embryonic development

d. all of the above

Question 8

All genes have only two possible alleles.

Select one:

True

False

Question 9

The presence of membrane-bound organelles is characteristic of â¦

Select one:

a. prokaryotes

b. viruses

c. bacteria

d. eukaryotes

Question 10

What are the building blocks of proteins?

Select one:

a. fatty acids

b. amino acids

c. nucleic acids

d. all of the above

Question 11

During which phase of the cell cycle does DNA replication occur?

Select one:

a. Mitosis

b. Interphase

c. Meiosis

d. Replicosis

Question 12

Which of the following characteristic is shared among fungi and animals?

Select one:

a. autotrophic

b. heterotrophic

c. cell walls

d. absorb nutrients

Question 13

A error in DNA replication that goes unrepaired is a â¦

Select one:

a. chromosome

b. chromatid

c. mutation

d. none of the above

Question 14

Alternate forms of a gene are called ________.

Select one:

a. chromatids

b. chromosomes

c. ribosomal subunits

d. alleles

Question 15

The physical expression of a genotype is the phenotype.

Select one:

True

False

Question 16

In complete dominance, a heterozygous genotype results in â¦

Select one:

a. a recessive phenotype

b. a dominant phenotype

c. a third and unique phenotype

d. none of the above

Question 17

Which theory explains the evolution of eukaryotes from prokaryotes?

Select one:

a. phagocytosis

b. endosymbiosis

c. pinocytosis

d. none of the above

Question 18

Which scientist experimented with plants to describe patterns of inheritance?

Select one:

a. Mendel

b. Chase

c. Einstein

d. Watson

Question 19

Which cellular organelle contains aerobic cellular respiration?

Select one:

a. chloroplasts

b. mitochondria

c. nucleus

d. lysosome

Question 20

Which of the following statements is false?

Select one:

a. Haploid gametes are formed by meiosis

b. Mitosis forms genetically identical daughter cells

c. Mitosis results in the formation of four daughter cells from a single parent cell

d. Mitosis forms diploid daughter cells from a diploid parent cell

Question 21

The first forms of life on Earth were ________.

Select one:

a. plants

b. microorganisms

c. birds

d. dinosaurs

Question 22

Which of the following is used to separate chromosomes during nuclear division?

Select one:

a. cytoskeleton

b. microtubules

c. actin and myosin

d. amoeboid movement

e. all of the above

Question 23

Which generation is most dominant in more primitive plants?

Select one:

a. bryophyte

b. sporophyte

c. gametophyte

d. androphyte

Question 24

Which of the following is characteristic of plants?

Select one:

a. autotrophic

b. contain chloroplasts

c. multicellular

d. all of the above

Question 25

During which phase of mitosis do chromosome line up along the middle of the cell?

Select one:

a. prophase

b. metaphase

c. anaphase

d. telophase

Question 26

During which phase of mitosis does DNA condense into distinct chromosomes?

Select one:

a. prophase

b. metaphase

c. anaphase

d. telophase

Question 27

The process by which DNA is used as a template to make new DNA is â¦

Select one:

a. translation

b. replication

c. transcription

d. allocation

Question 28

Which of the following is characteristic of plant but not animal cells?

Select one:

a. chloroplasts

b. water vacuole

c. cell wall

d. all of the above

Question 29

Which meiotic division is most like mitosis?

Select one:

a. Meiosis I

b. Meiosis II

c. Meiosis III

d. Meiosis IV

Question 30

Which enzyme catalyzes replication?

Select one:

a. DNA polymerase

b. RNA polymerase

c. Ribosome

d. all of the above

1.. Polymorphisms for a given trait are relatively common in most species. Discuss the possible advantages or polymorphisms in terms of evolutionary fitness. Be sure to relate your discussion to a specific example. It is also possible that organisms showing more heterozygosity may actually be less fit. Describe one such possible scenario.

2. In the peppered moth (Biston betularia), black individuals may be either homozygous (A1A1) or heterozygous(A1A2), whereas the pale gray moths are homozygous (A2A2). Suppose that in a sample of 250 moths from one locality, 108 are black, and 142 are gray.

3. Retrace the history of primate evolution from early primates to monkeys, apes and hominins. When did some ofthe significant divergences occur (such as between the prosimians and the monkeys or between the chimps and hominins)? What was happening with the continents and the major climatic conditions during these times?What are the major species (including the extinct species) along the human lineage after the split with the chimps and bonobos? Where did many of these events occur on the globe and when?

4. Spencer Wells described his study how the genetic markers in humans are being used to infer the historical geographical distribution of humans and the dispersal of our ancestors. Explain how the genetic markers on our DNA (from blood samples) helps us understand that history. What are the techniques he is using? What is the nature of the evidence? What are the major conclusions about the journey of our ancestors out of Africa?What were the major migrations of humans to all the other continents? Approximately when did each migration occur and what were the major paths? How does the evidence support these conclusions? What Supporting evidence besides the DNA evidence is being used to support these conclusions?

5. Provide an adaptive and a non adaptive hypothesis for the evolutionary loss of useless organs, such as eyes in many cave-dwelling animals. How might these hypotheses be tested?

6. Directional selection is one of the models of natural selection. Describe this type of selection in terms of the frequencies of advantageous alleles over time. What is the trend over time? What is the eventual outcome for this allele as long as no other evolutionary factors intervene? Describe at least one good example of directional selection.

7. Consider the first copy of an allele for insecticide resistance that arises by mutation in a population of insects exposed to an insecticide. Is this mutation an adaptation? If, after some generations, we find that most of the population is resistant, is the resistance an adaptation? If we discover genetic variation for insecticide resistance in a population that has had no experience of insecticides, is that variation an adaptation? If an insect population is polymorphic for two alleles, each of which confers resistance against one of two pesticides that are alternately applied, is that variation an adaptation? Or is each of the two resistance traits an adaptation?Explain your reasoning thoroughly.

8. Suppose that a mutation in a species of annual plant increases allocation to chemical defenses against herbivores, but decreases production of flowers and seeds (i.e., there is an allocation trade-off). What would you have to measure in a field study in order to predict whether or not the frequency of the mutation will increase?

9. In many socially monogamous species of parrots and other birds, both sexes are brilliantly colored or highly ornamented. Is sexual selection likely to be responsible for the coloration and ornaments of both sexes? How can there be sexual selection in pair-bonding species with a 1:1 sex ratio, since every individual presumably obtains a mate? Which of the models of sexual selection described in the book might account for these species characteristics?

10. Kin selection explains why organisms may provide benefits to relatives. Is there a conflict between the principle of kin selection and the evolution of siblicide and abortion?

11.Many species of albatrosses and other seabirds nest in colonies on islands. The adult search for food at sea,sometimes over great distances. Some ecologists who study seabirds turn to their favorite topic of discussion in a bar one evening, and one says, âI can imagine an albatross genotype that destroys the eggs of nestlings of its colony mates when the parents are away foraging, and leaves them dead without eating them. Do you think such a behavior would evolve?â One of his companions says, âYes, because it would make more food available for the albatross and its offspring.â Another says, âNo, because it would threaten the survival of the population.â The fourth says, âYouâre both wrong. I have a different explanation for why albatrosses donât kill othersâ chicks.â What is the fourth ecologistâs explanation, and why does she think her companions are wrong?

12. The concept of a species is fundamental to understanding biology, yet there may not be one definition that fits all âtypesâ of organisms (e.g. animals, plants, fungi, bacteria, slime mold, lichens, etc.). Discuss several of the definitions of a species as presented in class and present your own definition for a species. Compare the strengths and weaknesses of each definition. Ernst Mayr is strong proponent of the biological species concept.How does he justify his position? Do you agree or disagree? If we employ the biological species concept, when did species first exist? What were organisms before then, if not species? What might the consequences of the emergence of species be for processes of adaptation and diversification? Be sure to explain your reasoning thoroughly.

13. The process of speciation ultimately involves the development of reproductive isolation between two related populations of organisms. Describe the various types of both prezygotic and postzygotic reproductive isolation and give an example of each.

14. Respond to the following quote from the character named Mr. Spock in âStar Trekâ:âA truly successful parasite is commensal, living in amity with its host, or even giving it positive advantages, as for instance, the protozoans who live in the digestive system of your termites and digest for them the wood they eat. A parasite that regularly and inevitably kills its host cannot survive long, in the evolutionary sense, unless it multiplies with tremendous rapidity ... it is not pro-survival.âFrom what you have learned in this course, do you agree or disagree with Spock? How can you apply your reasoning to the relative âfitnessâ of HIV which causes AIDS, the Ebola virus which causes hemorrhagic fever,fleas which suck blood from dogs, or the prokaryotic ancestors of mitochondria and chloroplasts?

15. In many species of birds and mammals, clutch size is larger in populations at high latitudes than in population sat low latitudes. Species of lizards and snakes at high latitudes often have smaller clutches, however, and are more frequently viviparous (bear live young rather than laying eggs), than low-latitude species. What selective factors might be responsible for these patterns? Explain your reasoning.

16. The popular media often presents evolution as being a predictable process with a definite goal. For instance, in one âStar Trek: Voyagerâ episode, the captain instructs the shipâs computer to extrapolate the âprobable courseâ of evolution of hadrosaurs (a bipedal dinosaur), if hadrosaurs had been removed from Earth before the Cretaceous-Tertiary (K-T) Extinction and allowed to evolve on another planet. What information about the hadrosaursâ new environment would have been useful in developing the best possible prediction? Given what you know on genetic drift and selective agents, is it possible to accurately predict the long-term course of evolution?

17. Young children often develop strong food preferences that sometimes seem bizarre to their parents --- such as wanting to eat only a certain food prepared in a familiar way, or being reluctant to each new foods or foods with strong or bitter tastes (like coffee and some vegetables). Develop an evolutionary explanation for such preferences. What evidence would you gather to investigate your hypothesis and rule out alternative explanations?

18. Many organisms, such as mammals, only reproduce by sexual means. Other organisms are exclusively asexual,such as many of the bacteria and fungi. And still others have ways of propagating by both sexual and asexualmeans. Discuss the relative advantages and disadvantages of each mode of reproduction. Why arenât all organisms sexual critters? Why are many asexual organisms still very successful as evidenced by the pure abundance and diversity? What is the adaptive significance of having different genders (e.g. male and female)?In other words, why sex?

19. How might differential expression and regulation by Hox genes contribute to mosaic evolution in which different segments of an animal body plan evolve different morphology?

20. Development of a morphological structure involves many different types of gene products, including transcription factors, signaling proteins, and âeffectorâ genes such as enzymes. When a morphological change occurs in a single mutational step, which of these types might be more or less likely to be involved? Within a gene, would such single-step events be more likely to involve coding or non-coding sequences, and what characteristics of the geneâs function might affect this likelihood?

21. Since 2001, the complete DNA sequences of the genomes of many people have been determined. If humans,along with other forms of life, have evolved from a common ancestor, what evidence of this would be expected in the human genome? In what ways might the history and processes of evolution help us interpret and make sense of the human genome sequence data?

22. Paleontologists and some biologists commonly infer function, and even behavior, from anatomical details.Skeletal features, for example, are often used to infer that an extinct mammal (such as an early hominid) was highly, somewhat, or not at all arboreal. This inference assumes a good fit of form to function (i.e., optimal form). Can this assumption be justified?

23. Stephen Jay Gould (1989) and others have argued that the evolution of self-conscious, intelligent species (i.e.humans) was historically contingent: it would not have occurred had any of a great many historical events been different. The philosopher Daniel Dennett (1995) and others have disagreed, arguing that convergent evolution is so common that if humans had not evolved, some other lineage would probably have given rise to a species with similar mental abilities. What do you think, and why? If Gouldâs position is right, what are its philosophical implications, if any?

24. Explain how Intelligent Design was determined as a religious view rather than a scientific view in the court casein Dover, PA. Should a scientific explanation of evolution be included in a science curriculum in K-12 schools?How is science and religion different in how they seek answers to questions? How is term "theory" used differently in science than in everyday English use? What is biological evolution? What evidence is used to support the scientific explanation of evolution? Is it possible to accept scientific explanations without rejecting religious faith?

25. Discuss how a creationist versus an evolutionary biologist might explain some human characteristics and the implications of their differences. Sample characteristics: eyes; wisdom teeth; individually unique friction ridges(fingerprints); five digits rather than some other number; susceptibility to infections; fever when infected;variation in sexual orientation; limited life span.