Bio exam 2

During chordate evolution, what is the sequence (from earliest to most recent) in which the following structures arose? 1. amniotic egg 2. paired fins 3. Jaws 4. swim bladder 5. four-chambered heart

2, 3, 4, 1, 5

When a mycelium infiltrates an unexploited source of dead organic matter, what are most likely to appear within the food source soon thereafter?

Fungal enzymes

Female birds lay their eggs, thereby facilitating flight by reducing weight. Which "strategy" seems most likely for female bats to use to achieve the same goal?

Limit litters to a single embryo

Which eukaryotic kingdom includes members that are the result of endosymbioses that included an ancient aerobic bacterium and an ancient cyanobacterium?

Plantae

A billionaire buys a sterile volcanic island that recently emerged from the sea. To speed the arrival of conditions necessary for plant growth, the billionaire might be advised to aerially sow what over the island?

Soredia

Why have biologists hypothesized that the first land plants had a low, sprawling growth habit?

The ancestors of land plants, green algae, lack the structural support to stand erect in air.

Which of the following statements about human evolution is correct

The upright posture and enlarged brain of humans evolved separately.

In a comparison of birds and mammals, having four limbs is _____.

a shared ancestral character

Neutral theory proposes that _____

a significant proportion of mutations are not acted upon by natural selection

In what respect do hominins differ from all other anthropoids?

bipedal posture

Which of the following pairs are the best examples of homologous structures?

bones in the bat wing and bones in the human forelimb

All types of muscle tissue have _____.

interactions between actin and myosin

Chordate pharyngeal slits appear to have functioned first as _____.

suspension-feeding devices

The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8-25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can now enter. The uneaten seeds may subsequently germinate. The taller a Brazil nut tree is, _____. 1. the more valuable it is as a source of lumber 2. the less useful it is to harpy eagles 3. the greater its photosynthetic rate relative to neighboring plants

1 and 3

Harold and Kumar are pre-med and pre-pharmacy students, respectively. They complain to their biology professor that they should not have to study about plants because plants have little relevance to their chosen professions. 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

2 and 3

What adaptations should one expect of the seed coats of angiosperm species whose seeds are dispersed by frugivorous (fruit-eating) animals, as opposed to angiosperm species whose seeds are dispersed by other means? 1. The exterior of the seed coat should have barbs or hooks. 2. The seed coat should contain secondary compounds that irritate the lining of the animal's mouth. 3. The seed coat should be able to withstand low pHs. 4. The seed coat, upon its complete digestion, should provide vitamins or nutrients to animals. 5. The seed coat should be resistant to the animals' digestive enzymes.

3 and 5

Which of the following animals most likely uses the largest percentage of its energy budget for homeostatic regulation?

A bird living year round in the desert

Which of the following would be useful in creating a phylogenetic tree of a taxon? I) morphological data from fossil species II) genetic sequences from living species III) behavioral data from living species

All three

The following figure depicts the outline of a large fairy ring that has appeared overnight in an open meadow, as viewed from above. The fairy ring represents the furthest advance of this mycelium through the soil. Locations A-D are all 0.5 meters below the soil surface. What is the most probable location of the oldest portion of this mycelium?

C

The following figure depicts the outline of a large fairy ring that has appeared overnight in an open meadow, as viewed from above. The fairy ring represents the furthest advance of this mycelium through the soil. Locations A-D are all 0.5 meters below the soil surface. At which location should one find the lowest concentration of fungal enzymes, assuming that the enzymes do not diffuse far from their source, and that no other fungi are present in this habitat?

D

A botanist discovers a new species of plant in a tropical rainforest. After observing its anatomy and life cycle, she 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

Which principle of heat exchange is the most important explanation for why birds look larger in colder weather because they fluff their feathers?

Fluffing creates a pocket of air near the bird that acts as insulation.

The cycads, a mostly tropical phylum of gymnosperms, evolved about 300 million years ago and were dominant forms during the Age of the Dinosaurs. Though their sperm are flagellated, their ovules are pollinated by beetles. These beetles get nutrition (they eat pollen) and shelter from the microsporophylls. Upon visiting megasporophylls, the beetles transfer pollen to the exposed ovules. In cycads, pollen cones and seed cones are borne on different plants. Cycads synthesize neurotoxins, especially in the seeds, that are effective against most animals, including humans. On the Pacific island of Guam, large herbivorous bats called "flying foxes" commonly feed on cycad seeds, a potent source of neurotoxins. The flying foxes do not visit male cones. Consequently, what should be true?

Flying foxes can be dispersal agents of cycad seeds if the seeds sometimes get swallowed whole (in other words, without getting chewed).

Why are mycorrhizal fungi superior to plants at acquiring mineral nutrition from the soil?

Fungi secrete extracellular enzymes that can break down large molecules.

The most direct ancestors of land plants were probably _____.

Green algae

With which of the following statements would a biologist be most inclined to agree?

Humans and other apes represent divergent lines of evolution from a common ancestor.

In the United States and Canada, bats use one of two strategies to survive winter: They either migrate south, or they hibernate. Recently, those that hibernate seem to have come under attack by a fungus, Geomyces destructans (Gd), an attack that is occurring from Missouri to southern Canada. Many infected bats have a delicate, white filamentous mat on their muzzles, which is referred to as white-nose syndrome (WNS). The fungus invades the bat tissues, causes discomfort, and awakens the bat from its hibernation. The bat fidgets and wastes calories, using up its stored fat. The bat then behaves abnormally, leaving its cave during daytime in winter to search for food. Their food, primarily insects, is scarce during the winter, and the bats ultimately starve to death. Since 2007, it is estimated that up to one million bats have perished from WNS. The Gd mat on the fur of the bats should be expected to consist of _____.

Hyphae

In a cool environment, an ectotherm is more likely to survive an extended period of food deprivation than would an equally sized endotherm because the ectotherm _____

Invests little energy in temperature regulation

Primate evolution and behavior, such as hunting skills, have been directed in part by the development of depth perception. What anatomical change made depth perception possible?

Movement of the eyes to the front of the head

Which of the following would, if it had acted upon a gene, prevent this gene from acting as a reliable molecular clock?

Natural selection

The presence of a swim bladder allows the typical ray-finned fish to stop swimming and still _____.

Not Sink

Which of the following is a characteristic of all chordates at some point during their life cycle?

Post-anal tail

If all fungi in an environment that perform decomposition were to suddenly die, then which group of organisms should benefit most, due to the fact that their fungal competitors have been removed?

Prokaryotes

A woman standing and watching the stars on a cool, calm night will lose most of her body heat by _____.

Radiation

It has been hypothesized that fungi and plants have a mutualistic relationship because plants make sugars available for the fungi's use. What is the best evidence in support of this hypothesis?

Radioactively labeled sugars produced by plants eventually show up in the fungi with which they are associated.

An example of an ectothermic organism that has few or no behavioral options when it comes to its ability to adjust its body temperature is a _____.

Sea star living in the deep ocean

The following figure depicts the outline of a large fairy ring that has appeared overnight in an open meadow, as viewed from above. The fairy ring represents the furthest advance of this mycelium through the soil. Locations A-D are all 0.5 meters below the soil surface. In which of the following human mycoses should one expect to find a growth pattern most similar to that of the mycelium that produced the fairy ring?

Skin mycoses

The type of muscle tissue surrounding the intestines and blood vessels is _____.

Smooth Muscle

Fungi have an extremely high surface-area-to-volume ratio. What is the advantage of this to an organism that gets most of its nutrition through absorption?

The larger surface area allows for more material to be transported through the cell membrane.

An elephant and a mouse are running in full sunlight, and both overheat by the same amount above their normal body temperatures. When they move into the shade and rest, which animal will cool down faster?

The mouse will because it has the higher surface-area-to-volume ratio.

Rose-picker's disease is caused by the yeast Sporothrix schenkii (S. schenkii). The yeast grows on the exteriors of rose-bush thorns. If a human gets pricked by such a thorn, the yeasts can be introduced under the skin. The yeasts then assume a hyphal morphology and grow along the interiors of lymphatic vessels until they reach a lymph node. This often results in the accumulation of pus in the lymph node, which subsequently ulcerates through the skin surface and then drains. Humans have immune systems in which lymph nodes are important, because many phagocytes and lymphocytes reside there. Given that a successful infection by S. schenkii damages lymph nodes themselves, which of the following is most probable?

Their conversion from yeast to hyphal morphology allows such fast growth that the body's defenses are at least temporarily overwhelmed.

It is believed that the coelacanths and lungfish represent a crucial link between other fishes and tetrapods. What is the major feature in these fish in support of this hypothesis?

Their fins have skeletal and muscular structures similar to amphibian limbs.

The various taxonomic levels (for example, phyla, genera, classes) of the hierarchical classification system differ from each other on the basis of _____.

Their inclusiveness

Liverworts, hornworts, and mosses are grouped together as the Bryophytes. Besides not having vascular tissue, what do they all have in common?

They require water for reproduction.

Given that phylogenies are based on shared derived characteristics, which of the following traits is useful in generating a phylogeny of species W, X, Y, and Z?

Trait 2

If you were using cladistics to build a phylogenetic tree of cats, which of the following would be the best outgroup?

Wolf

Why do adult urochordates (tunicates) lack notochords, even though larval urochordates have them? Larvae use notochords to _____.

aid in swimming; adults are sessile and thus no longer propel themselves.

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

Orchid seeds are tiny, with virtually no endosperm and with miniscule cotyledons. If such seeds are deposited in a dark, moist environment, then which of the following represents the most likely means by which fungi might assist in seed germination, given what the seeds lack?

by providing the embryos with some of the organic nutrients they have absorbed

To apply parsimony to constructing a phylogenetic tree, _____.

choose the tree that represents the fewest evolutionary changes, either in DNA sequences or morphology

Some beetles and flies have antler-like structures on their heads, much like male deer do. The existence of antlers in beetle, fly, and deer species with strong male-male competition is an example of _____.

convergent evolution

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

Which feature seen in chytrids supports the hypothesis that they diverged earliest in fungal evolution?

flagellated spores

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 functional significance of porous septa in certain fungal hyphae is most similar to that represented by which pair of structures in animal cells and plant cells, respectively?

gap junctions — plasmodesmata

About 450 million years ago, the terrestrial landscape on Earth would have _____.

had non-vascular green plants similar to liverworts forming green mats on rock

Many mammals have skins and mucous membranes that are sensitive to phenolic secretions of plants like poison oak (Rhus). These secondary compounds are primarily adaptations that _____.

inhibit herbivory

Fishes that have swim bladders can regulate their density and, thus, their buoyancy. There are two types of swim bladder: physostomous and physoclistous. The ancestral version is the physostomous version, in which the swim bladder is connected to the esophagus via a short tube (see the figure above). The fish fills this version by swimming to the surface, taking gulps of air, and directing them into the swim bladder. Air is removed from this version by "belching." The physoclistous version is more derived, and has lost its connection to the esophagus. Instead, gas enters and leaves the swim bladder via special circulatory mechanisms within the wall of the swim bladder. If a ray-finned fish is to both hover (remain stationary) in the water column and ventilate its gills effectively, then what other structure besides its swim bladder will it use?

its opercula

Which extant chordates are postulated to be most like the earliest chordates in appearance?

lancelets

If haustoria from the fungal partner were to appear within the photosynthetic partner of a lichen, and if the growth rate of the photosynthetic partner consequently slowed substantially, then this would support the claim that _____.

lichens are not purely mutualistic relationships

Once labor begins in childbirth, contractions increase in intensity and frequency, causing more contractions to occur until delivery. The increasing labor contractions of childbirth are an example of which type of regulation?

positive feedback

Some molecular data place the giant panda in the bear family (Ursidae) but place the lesser panda in the raccoon family (Procyonidae). If the molecular data best reflect the evolutionary history of these two groups, then the morphological similarities of these two species is most likely due to _____.

possession of analogous (convergent) traits

Which characteristic is common to all the modern representatives of all major reptilian lineages (turtles, lepidosaurs, crocodilians, and birds)?

presence of a notochord

What kind of evidence has recently made it necessary to assign the prokaryotes to either of two different domains, rather than assigning all prokaryotes to the same kingdom?

rRNA genes

The best classification system is that which most closely _____.

reflects evolutionary history

Near a goose's abdomen, the countercurrent arrangement of the arterial and venous blood vessels causes the _____.

temperature difference between the contents of the two sets of vessels to be minimized

Due to its system of air sacs connected to the lungs, the respiratory system of birds is arguably the most effective respiratory system of all air-breathers. Upon inhalation, air first flows into posterior air sacs, then into the lungs, and then into anterior air sacs on the way to being exhaled. Thus, there is one-way flow of air through the lungs, along thousands of tubules called parabronchi. The one-way flow of air along parabronchi makes what type of gas exchange mechanism possible, at least theoretically?

the same as that occurring in fish gills

The following questions refer to this phylogenetic tree, depicting the origins of life and of the three domains. Horizontal lines indicate instances of gene or genome transfer. A possible phylogenetic tree for the three domains of life.If the early history of life on Earth is accurately depicted by the figure above, then which statement is most in agreement with the hypothesis proposed by this tree? What evidence do paleobotanists look for that indicates the movement of plants from water to land?

waxy cuticle to decrease evaporation from leaves

The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8-25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can now enter. The uneaten seeds may subsequently germinate. The same bees that pollinate the flowers of the Brazil nut trees also pollinate orchids, which are epiphytes (in other words, plants that grow on other plants); however, orchids cannot grow on Brazil nut trees. These observations explain _____.

why Brazil nut trees do not set fruit in monoculture plantations