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Biology Of Gymnosperms And Angiosperms Flashcards

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Gametangia Reproductive strcutures that protect gametes as they develop
Pollen Reproductive structures that allow sperm to be transported in the abscence of water
Seeds Reproductive structures that provide stored nutrients and a protective coat so that offspring can be dispersed by wind away from parent plant
Fruit Reproductive structures that provide nutritious tissue around seeds that facilitate dispersal by animals
Angiosperm only Fruit
All land plants except angiosperms Gametangia
Gymnosperms and Angiosperms Pollen and seeds
The appearance of cuticle and stomata correlated with what event in the evolution of land plants? Growth on land
What impact would the spraying of fungicide have on soil-dwelling organisms? Plant and animal diversity would decrease due to reduced amounts of available phosphorus and nitrogen.
When pathogenic fungi are found growing on the roots of grape vines, grape farmers sometimes respond by covering the ground around their vines with plastic sheeting and pumping a gaseous fungicide into the soil. The most important concern of grape farmers who engage in this practice should be that the _____. fungicide might also kill mycorrhizae
The following statements describe something about the body structures or functions of fungi Some fungi secrete digestive enzymes into the environment and then absorb the digested nutrients.
Some fungi can grow as either filamentous or single-celled forms.
All fungi are heterotrophs; some species live as decomposers and others as symbionts
Mycelia are made up of small-diameter hyphae that form an interwoven mass, providing more surface area for nutrient absorption.
Fungal mycelia _____ have a large surface area composed of branching hyphae
Why is it more difficult to treat fungal infections than bacterial infections in humans? Fungal and animal cells and proteins are similar. Thus, drugs that disrupt fungal cell or protein function may also disrupt human cell or protein function.
Based on the idea that fungi have pores between their cell walls, which allow cytoplasm to move from one end of the mycelium to the other, which of the following hypotheses is the most plausible? If a single mycorrhizal fungus formed symbiotic associations with more than one tree, carbon could travel from one plant to another
The term gymnosperm refers to plants _____. with "naked seeds"
Molecular phylogenies show all land plants are a monophyletic group. This suggests that _____. there was a single transition from aquatic to terrestrial habitats.
You find a green organism in a pond near your house and believe it is a plant, not an alga. The mystery organism is most likely a plant and not an alga if it ____ is surrounded by a cuticle
Fungal digestion _____ is extracellular, meaning that it takes place outside the organism.Fungi are absorptive heterotrophs that release digestive enzymes to the external environment and absorb the digested nutrients.
Based on the graphs in the figure above, which of the following plant species is most likely NOT to form mycorrhizal associations?

Carex flacca (graph a)

The adaptive advantage associated with the filamentous nature of fungal mycelia is primarily related to _____. an extensive surface area well suited for invasive growth and absorptive nutrition.
In graph (b) in the figure above, which of the following best explains the data given about Lotus corniculatus?
This plant forms multiple AMF associations, growing best with increased fungal diversity
What is the major difference between Bromus erectus (graph f) and the other plant species (graphs a-d) included in the study? Bromus erectus is unaffected by AMF diversity.
In most fungi, karyogamy does not immediately follow plasmogamy, which consequently _____. results in heterokaryotic or dikaryotic cells
The hyphae of arbuscular mycorrhizal fungi (AMF) form bushy structures after making contact with the plasma membrane of a root cell.Why?
They increase the surface area available for the transfer of nutrients.
According to the fossil record, plants colonized terrestrial habitats _____. in conjunction with fungi that helped provide them with nutrients from the soil
Which of these characteristics is shared by algae and seed plants? chloroplasts
Cuticle, stomata, and vascular tissue are all key adaptations enabling land plants to _____. colonize land.
Fruit is most important in facilitating _____. seed dispersal.
Which of the following was a challenge to the survival of the first land plants? desiccation.
A botanist discovers a new species of plant in a tropical rain forest. After observing its anatomy and life cycle, he notes the following characteristics: flagellated sperm, xylem with tracheids, separate gametophyte and sporophyte generations with the sporophyte dominant, and no seeds. This plant is probably most closely related to _____. ferns.
Big Bend National Park in Texas is mostly Chihuahuan desert, where rainfall averages about 10 inches per year. Yet, it is not uncommon when hiking in this bone-dry desert to encounter mosses and ferns. One such plant is called "flower of stone." It is not a flowering plant, nor does it produce seeds. Under arid conditions, its leaflike structures curl up. However, when it rains, it unfurls its leaves, which form a bright green rosette on the desert floor. Consequently, it is sometimes called the "resurrection plant." At first glance, it could be a fern, a true moss, or a spike moss.


Which of the following features is most important for true mosses and ferns to reproduce in the desert? 		either that their gametophytes grow close together, or that they be hermaphroditic
In terms of alternation of generations, the internal parts of the pollen grains of seed-producing plants are most similar to a _____. fern gametophyte bearing only antheridia.
The generative cell of male angiosperm gametophytes is haploid. This cell divides to produce two haploid sperm cells. What type of cell division does the generative cell undergo to produce these sperm cells? mitosis
Angiosperms are the most successful terrestrial plants. Which of the following features is unique to them and helps account for their success? fruits enclosing seeds
The fruit of the mistletoe, a parasitic angiosperm, is a one-seeded berry. In members of the genus Viscum, the outside of the seed is viscous (sticky), which permits the seed to adhere to surfaces such as the branches of host plants or the beaks of birds. What should be expected of the fruit if the viscosity of Viscumseeds is primarily an adaptation for dispersal rather than an adaptation for infecting host plant tissues? It should ______. be nutritious to the dispersing organisms.
Which adaptations of land plants are likely to provide Harold with future patients?
I) sporophyte dominance
II) defenses against herbivory
III) adaptations related to wind dispersal of pollen 		II and III
Which feature of cycads distinguishes them from most other gymnosperms?
1. They have exposed ovules.
2. They have flagellated sperm.
3. They are pollinated by animals. 		2 and 3
Which answer best explains how certain patterns of histone acetylation or DNA methylation could influence whether a cell became a muscle cell or a brain cell? They could affect which sets of genes are transcribed in different cell types.
Which of the following is most critical for the association between histones and DNA? Histones are positively charged.
If cells of an individual contain the same set of genes, how do these cells become different from each other during development? Differences in extracellular signals received by each cell lead to differences in the types of regulatory proteins present in each cell.
Imagine that you've discovered a regulatory sequence thousands of base pairs away from the promoter and that when this sequence is lost due to mutation, levels of gene expression decrease sharply. This sequence is most likely ______. An enhancer
Alternative RNA splicing allows for the number of different _________ to exceed the number of different __________. Proteins; genes
Why is "chain reaction" an appropriate part of the term PCR? Newly synthesized DNA segments serve as templates in subsequent cycles. A chain reaction occurs when a product of one reaction set (or cycle in the case of PCR) is a reactant in a following set, causing the reaction to spread (as with neutrons in nuclear fission). For PCR, this means that the amount of DNA doubles in each cycle.
Compare and contrast PCR with the DNA synthesis that occurs in cells. Both produce copies of a template DNA

Both rely on DNA polymerase

Both rely on primers
PCR Copies only a specific target sequnce

Occurs at a high temperature

Uses Taq polymerase
Cellular DNA synthesis Copies entire genome
One morphological feature of modern cetaceans is a vestigial pelvic girdle. If it is determined that the cetacean lineage diverged from the artiodactyls' lineage afterthe divergence of pigs and other artiodactyla, then the vestigial pelvic girdle of cetaceans should be considered a shared _____. derived character of the cetaceans
What is plausible evidence supporting the hypothesis that birds evolved from dinosaurs?
Fossilized transitional forms are discovered that possess features of birds and dinosaurs yet are difficult to classify into either group.
Why are human and chimpanzee DNA 96 percent similar? The two species descended from a recent common ancestor.
What must be true of any organ described as vestigial? It must be homologous to some feature in an ancestor.
Which of the following is the best modern definition of evolution? Descent with modification.
Given a population that contains genetic variation, what is the correct sequence of the following events under the influence of natural selection?
1. Well-adapted individuals leave more offspring than do poorly adapted individuals.
2. A change occurs in the environment.
3. Genetic frequencies within the population change.
4. Poorly adapted individuals have decreased survivorship. 		2 → 4 → 1 → 3
After the drought of 1977, researchers hypothesized that on the Galápagos island Daphne Major, medium ground finches with large, deep beaks survived better than those with smaller beaks because they could more easily crack and eat the tough Tribulus cistoides fruits. A tourist company sets up reliable feeding stations with a variety of bird seeds (different types and sizes) so that tourists can get a better look at the finches. Which of these events is now most likely to occur to finch beaks on this island? Increased variation in beak size and shape over time.
A proficient engineer can easily design skeletal structures that are more functional than those currently found in the forelimbs of such diverse mammals as horses, whales, and bats. The actual forelimbs of these mammals do not seem to be optimally arranged because _____. Natural selection is generally limited to modifying structures that were present in previous generations and in previous species.
A researcher wants to know if gene flow is contributing to evolution of drought tolerance of pitcher plants in a specific bog. As a control, she should Determine if the population is in Hardy-Weinberg equilibrium.
Three-spined stickleback fish (Gasterosteus aculeatus) show substantial heritable variation in gill-raker length related to differences in their diets. Longer gill rakers appear to function better for capturing open-water prey, while shorter gill rakers function better for capturing shallow-water prey. Which of the following types of selection is most likely to be found in a large lake (open water in the middle and shallow water around the sides) with a high density of these fish? Disruptive selection.
Soon after the island of Hawaii rose above the sea surface (somewhat less than one million years ago), the evolution of life on this new island should have been most strongly influenced by _____. The founder effect.
Natural Selection Consistently causes a population to become better adapted to its environment.

A result of differential success in reproduction.

Cannot cause a harmful allele to become more common.
Genetic Drift Responsible for the Founder Effect

Responsible for the Bottleneck Effect

Causes allele frequencies to fluctuate randomly
Gene Flow Can introduce new alleles into a population's gene pool.

A result of the movement of fertile individuals or their gametes.
Natural selection _____. Can favor beneficial mutations.
Biological, morphological, and phylogenetic species concepts allow biologists to identify evolutionarily independent groups because they all rely on criteria indicative of _____. No gene flow between populations.
Which of the following statements about species, as defined by the biological species concept, is (are) correct?
I. Biological species are defined by reproductive isolation.
II. Biological species are the model used for grouping extinct forms of life.
III. All members of a species can potentially interbreed. 		I and III.
Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species. Recently, these birds have been classified as eastern and western forms of a single species, the yellow-rumped warbler. Which of the following pieces of evidence, if true, would be cause for this reclassification? The two forms interbreed often in nature, and their offspring have good survival and reproduction.
Which two of the following have operated to increase divergence between mosquitofish populations on Andros?
1. improved gene flow
2. bottleneck effect
3. sexual selection
4. founder effect
5. natural selection 		3 and 5
Which is the first step in allopatric speciation? Physical isolation of two populations.
Which of the situations below describes vicariance? The Grand Canyon forms, separating two populations of squirrels on the North rim and the South rim.
There is an island in the middle of a large river that houses a large population of ants. Damming of the river causes the island to flood and only the highest points of the island are now above water. The ants cannot swim, so are now in multiple isolated populations. Which of the following best describes this event? This situation represents isolation by vicariance.
Reinforcement is most likely to occur when _____. Hybrids have lower fitness than either parent population.
A hybrid zone is properly defined as _____. An area where mating occurs between members of two closely related species, producing viable offspring.
Which statement is correct Synapomorphies identify monophyletic groups.
What is the difference between a branch and a node on a phylogenetic tree? A branch is a population through time; a node is where a population splits into two independent populations.
We know the streamlined bodies shown in the figure above are examples of homoplasy. If the following groups also had streamlined bodies, which of the groupings would give the most support to this body type being homologous? lizards, pterosaurs, dinosaurs, birds, synapsids, monotremes, marsupials, rodents, and primates
Archaeon Eon Origin of Earth

Oldest fossils of cells (prokaryotes appear)
Proterozoic Eon Oldest fossilsof eukaryotic cells appear
Paleozoic Era The Camnrian explosion
First tetrapods and insects appear
Mesozoic Era Origin of mammals
Dinosaurs evovle and radiate
Cenozoic Era Humans appear
Major radiation of pollinating insects
Cambrian Explosion Sudden increase in diversity of many animal phyla
In what way(s) could the evolution of animals that move throughout marine environments—from animals that live exclusively on the ocean floor—contribute to speciation and ecological diversification? The more mobile animals represent new species.
The presence of animals at an array of ocean depths creates selection pressure for the evolution of species that can eat them.
The ability to move off the ocean floor allows animals to exploit new resources.
Which of the following statements about adaptive radiation is correct? Adaptive radiation occurs within a single lineage
Which organisms are not examples of an adaptive radiation? Mammals and reptiles in the post-dinosaur age
True or false? Convergent evolution is said to have occurred if the mouse species on two islands with similar habitats are found to have similar characteristics even though they originated from different species that did not have these characteristics. True
Which Anolis lizard ecomorph has long legs? Trunk/ground
Which of the following statements about the evolution of Anolis lizards in the Caribbean islands is true? The phylogeny of ecomorphs on a given island reveals that adaptive radiation has taken place.
What was the main selective pressure behind the evolution of different Anolis lizard species in the Caribbean? Specific ecological niches.
Adaptive radiations can be a direct consequence of four of the following five factors. Select the exception. Genetic drift
Whatever its ultimate cause(s), the Cambrian explosion is a prime example of _____. Adaptive radiation
How do mass extinctions differ from background extinctions? Mass extinctions cause a larger proportion of organisms to go extinct than background extinctions
What evolutionary mechanism caused new alleles? Mutation
Researchers have identified closely related plant species native to Hawaii that have very diverse adaptations to their particular environments. Significant diversity among closely related species is a characteristic of Adaptive radiation
Which of the following statements about speciation is true? Speciation will occur more slowly if gene flow is high.
Many songbirds breed in North America in the spring and summer and then migrate to Central and South America in the fall. They spend the winter in these warmer areas, where they feed and prepare for the spring migration north and another breeding season. Two hypothetical species of sparrow, A and B, overwinter together in mixed flocks in Costa Rica. In spring, species A goes to the east coast of North America, and species B goes to the west coast. What can you say about the isolating mechanisms of these two species? Their winter habitat has no bearing on their degree of reproductive isolation.
Which of the following describes the most likely order of events in allopatric speciation? Genetic isolation, genetic drift, divergence.
What is genetic drift? A change in allele frequencies caused by random events.
Which of the following statements about reinforcement is true? Reinforcement is a type of natural selection.
In a hypothetical situation, a certain species of flea feeds only on pronghorn antelopes. In the western United States, pronghorns and cattle often associate with one another in the same open rangeland. Some of these fleas develop a strong preference for cattle blood and mate only with other fleas that prefer cattle blood. The host mammal can be considered as the fleas' habitat. If this situation persists, and new species evolve, this would be an example of _____.
Sympatric speciation and habitat isolation
A researcher notices that in a certain moth species, some females prefer to feed and lay eggs on domesticated solanaceous plants like potatoes and tomatoes. Other females prefer to feed and lay eggs on wild solanaceous plants like Datura. Both male and female moths primarily use scent to find these plants from afar. Females tend to mate where they feed, and the researcher finds a genetic basis for scent preference in these moths. Based on the above information, what might be occurring in this moth species? Divergence in sympatry
Male frogs give calls that attract female frogs to approach and mate. Researchers examined mating calls of closely related tree frogs in South America. If reinforcement is occurring, what would you expect if you compare the calls of the two species in zones of sympatry versus zones of allopatry?
Calls would be more different in areas of sympatry.
Which of the following characteristics, structures, or processes is common to bacteria and viruses? Genetic material composed of nucleic acid
Which of the following supports the argument that viruses are nonliving? They are not cellular.
Which of the following is characteristic of the lytic cycle? A large number of phages are released at a time.
What would the result be if a drug that blocks the action of polymerase was introduced into a virus-infected organism? The viral proteins would not be made and the virus would not be able to reproduce.
Viruses use the host's machinery to make copies of themselves. However, some human viruses require a type of replication that humans do not normally have. For example, humans normally do not have the ability to convert RNA into DNA. How can these types of viruses infect humans, when human cells cannot perform a particular role that the virus requires? The viral genome codes for specialized enzymes not in the host.
Can viruses evolve? Why or why not? Yes, their genetic makeup responds to natural selection
Which character separates bacteria from archaea? Bacteria have peptidoglycan in their cell wall
While examining a rock surface, you have discovered an interesting new organism. Which of the following criteria will allow you to classify the organism as belonging to Bacteria but not Archaea or Eukarya? Cell walls are made primarily of peptidoglycan
To establish a link between a specific bacterium and a skin disease, researchers have shown that bacterium was present in sick persons but not in healthy individuals. They isolated the bacterium in a pure culture and demonstrated that experimental healthy animals injected with this culture became sick. What other experiment do researchers need to perform to be absolutely sure that the bacterium is responsible for the disease? Isolate bacterium from an infected sick animal and demonstrate that it is the same bacterium as the one used for infection.
Organisms that synthesize their own C-C molecules from single-carbon starting materials are named _____, while those that absorb preformed C-C compounds are _____. autotrophs; heterotrophs
The purple non-sulfur bacterium Rhodospirillum grows best as a photoheterotroph. What are the most favorable sources of energy and carbon for this bacterium? Fructose and light

Would you predict that disease-causing bacteria, such as those listed in the Table above, obtain energy from light, organic molecules, or inorganic molecules?

Organic molecules
Protists and bacteria are grouped into different domains because _____. protists have a membrane-bounded nucleus, which bacterial cells lack
Which of the following statements is consistent with the assertion that protists are paraphyletic? Some protists evolved into other eukaryotic groups
According to the phylogenetic tree in the figure above, G. intestinalis constitutes a _____ group Paraphyletic
What advantage do organisms that reproduce sexually have over organisms that reproduce asexually? Their offspring may be more adaptable to changes in the environment
Which term describes the fusion of two gametes to form a diploid zygote? Syngamy
Which term describes the multicellular haploid form of a protist that shows alternation of generations? Gametophyte
Which of the following statements about Ulva's haploid stage is true? Haploid cells are produced by meiosis of diploid cells
How does the haploid form of Ulva "switch" to its diploid form? Gametophytes produce cells that undergo mitosis to produce gametes that fuse to form a zygote.
False, Organisms that exhibit alternation of generations reproduce sexually in the diploid stage Organisms that exhibit alternation of generations reproduce asexually in the diploid stage by producing haploid cells that form spores, which then germinate into haploid adults. The haploid adults produce haploid gametes that can then participate in sexual reproduction.
Which evidence is consistent with the endosymbiotic hypothesis for the origin of the mitochondrion? Mitochondria have their own ribosomes and manufacture their own proteins.
Chloroplasts arose via _____. endosymbiosis of cyanobacteria
Assume that some members of an aquatic species of motile, photosynthetic protists evolve to become parasitic to fish. They gain the ability to live in the fish gut, absorbing nutrients as the fish digests food. Over time, which of the following phenotypic changes would you expect to observe in this population of protists? loss of chloroplasts
Where on the phylogenetic tree should the origin of chloroplasts appear? At the base of Plantae
Imagine that there are twenty-five different species of protists living in a tide pool. Some of these species reproduce both sexually and asexually, and some of them can reproduce only asexually. The pool gradually becomes infested with disease-causing viruses and bacteria. Which species are more likely to thrive in the changing environment? the sexually reproducing species
Muscle cells differ from nerve cells mainly because they _____. express different genes.
In a nucleosome, the DNA is wrapped around _____. histones
Which of the following allows more than one type of protein to be produced from one gene?
alternative forms of RNA splicing
Several of the different globin genes are expressed in humans, but at different times in development. What mechanism could allow for this? differential gene regulation over time.
If a cell were unable to produce histone proteins, which of the following would be a likely effect? The cell's DNA couldn't be packed into its nucleus
Imagine that you've isolated a yeast mutant that contains histones resistant to acetylation. What phenotype do you predict for this mutant? The mutant will show low levels of gene expression
Histone acetyl transferases exert their effect on gene activity by _____. neutralizing positive charges on the lysines of histones
In eukaryotes, general transcription factors _____ bind to other proteins or to the TATA box
If the DNA sequence was substantially altered from one of the following, which would prevent the binding of the TATA-binding protein (TBP)? The promoter
Which of the following terms describes the DNA–protein complexes that look like beads on a string? Nucleosomes
Which of the following regulatory elements is not composed of DNA sequences? Activators
Which of the following regulatory DNA sequences might be located thousands of nucleotides away from the transcription start site of a gene? The Enhancer
Which of the following events in transcription initiation likely occurs last? RNA polymerase binds to the promoter of the gene
An example of a basal transcription factor is _____. the TATA-binding protein
The primary difference between enhancers and promoter-proximal elements is that enhancers _____. are at considerable distances from the promoter; promoter-proximal elements are close to the promoter
The reason for differences in the sets of proteins expressed in a nerve and a pancreatic cell of the same individual is that nerve and pancreatic cells contain different _____. sets of regulatory proteins
Alternative RNA splicing _____. can allow the production of proteins of different sizes and functions from a single mRNA
Which of the following is in the correct order for one cycle of polymerase chain reaction (PCR)? Denature DNA; anneal primers; extend primers
What information is critical to the success of polymerase chain reaction (PCR) itself? The DNA sequence of the ends of the DNA to be amplified must be known.
What information can not be obtained from the sequence of a gene? Whether the gene is methylated.
What is the polymerase chain reaction (PCR)? A method to amplify a fragment of DNA
How many DNA molecules would there be after four rounds of PCR if the initial reaction mixture contained two molecules? 32
During which step in the PCR cycle are nucleotides used? Extension
During which step in the PCR cycle do primers form bonds with a single-stranded template? Annealing
In a single polymerase chain reaction (PCR) cycle consisting of 15 seconds at 94°C, 30 seconds at 50°C, and 1 minute at 72°C, what is happening in the step run at 50°C? Primers are annealing to the DNA to be amplified.
What controls which DNA is amplified in PCR? the choice of primers