Mastering Biology Chapter 27 HW 1

Which of the following statements about vertebrates is true?

The development of an amniotic egg and internal fertilization allowed vertebrates to reproduce away from water.

Many blood-feeding parasites carry diseases but bed bugs do not. What is the most logical explanation for this?

The infectious agent is inactivated within the gut of the bed bug.

Select the correct statement about the evolution of animals.

The oldest generally accepted fossils of large animals range in age from 565 to 550 million years old.

Which characteristics define a chordate?

The presence of four specific morphological traits

Why do we often get an itchy red bump after being bitten by a bed bug?

The proteins injected by the bed bug trigger an inflammatory response in the human body.

How did the great transition from fish to tetrapod occur?

The transition occurred gradually over time, so there are many intermediate forms.

Which characteristic distinguishes echinoderms from the other two deuterostome lineages?

Their body plan

Bed bugs probably evolved from bat bugs. Which statement best describes how this likely happened?

There were two populations of bat bugs, one feeding on humans, and one on bats. Reproductive isolation, mutation, and natural selection led to speciation.

Which of the following is NOT a characteristic of all animals?

They have tissues, organs, and organ systems.

Why did Shubin and Daeschler search in the Canadian arctic for fossil evidence of the transition from fish to tetrapods?

They hypothesized that the transitional fossils were in sedimentary rocks older than 365 million years ago, when the first tetrapods appear in the fossil record.

Which of the following is a hypothesis the researchers were testing in this study?

Through evolution, periwinkle populations with a history of predation by crabs have become less vulnerable to crab predation.

What kind of habitat did tiktaalik live in?

Tiktaalik lived in a warm, freshwater swamp.

What is a transitional fossil?

Transitional fossils have features that are intermediate between ancestors and descendants.

Some invertebrates combine morphological simplicity with features of great structural or biochemical complexity. Select all correct examples of this statement. Select all that apply.

Trematodes are acoelomates that have effective defenses against attack by their hosts' immune system. Cnidarians are diploblasts that produce complex, capsule-like organelles.

Members of the phylum Mollusca __________.

are soft-bodied and often covered by a shell

Fossil steroid and molecular clock evidence suggests that animals originated __________.

both the first and the second choice listed

The phylum Arthropoda includes four major lineages: cheliceriforms (also called chelicerates); myriapods; insects and their relatives (together called hexapods); and crustaceans. Drag each word or phrase to the appropriate bin.

cheliceriforms- horseshoe crabs, arachnids, and possess claylike feeding appendages myriapods- millipedes and centipedes, exclusively terrestrial insects- butterflies, wings allow flight; body divided into head, thorax, and abdomen; and three pairs of walking legs crustaceans- primarily aquatic, crabs and isopods, two pairs of antenna

Which of the following is a characteristic of cnidarians?

gastrovascular cavity

An important trend in animal evolution was cephalization or development of a "head." An animal is said to show cephalization when it __________.

has an aggregation of sensory structures at the anterior end

Which of the following is the most inclusive term for an organism that obtains organic food material by eating other organisms or substances derived from them?

heterotroph

Ectoprocts and brachiopods are collectively referred to as __________

lophotrochozoans

Is this statement supported or not supported by the graph? For the species represented on this graph, body mass is directly proportional to brain size.

not supported

The animal phylum most like the protists that gave rise to the animal kingdom is _____.

Porifera

Why doesn't Dr. Logan feel the bed bug feeding on him?

The bed bug injects an anesthetic as it feeds.

Which of the following is a tetrapod? Select all that apply.

an amphibian a bird a reptile a mammal

Which of the following statements is correct?

All animals share a common ancestor.

Which of the following statements about deuterostomes is false?

All deuterostomes exhibit radial symmetry in their bodies.

Which of the following chordate groups include(s) humans? Select all that apply.

Amniotes Hominins Gnathostomes

What makes bed bugs different than most other blood-feeding parasites?

Bed bugs prefer humans over other hosts.

The diagnostic feature of Chondrichthyes is __________.

an endoskeleton of cartilage

The phylogenetic tree shown here displays the major clades of chordates.

- Descendants of organism (d) have limbs with digits - Rays and frogs have vertebrae; -Birds and ray-finned fishes have a notochord and jaws - Mammals and turtles are more closely related than are lungfishes and sharks - Organism (a) is a common ancestor of all chordates

Which evidence supports the hypothesis that four-limbed animals came from fish? Select all that apply.

-DNA analysis shows that fish are tetrapods' closest relatives. -The fossil record shows more and more tetrapod -like fish before the appearance of tetrapods about 365 million years ago. -Both fish and four-limbed animals are vertebrates.-Fish and four-limbed animals have very similar embryos.

Why have we NOT found examples in the fossil record of every animal that ever lived on Earth? Select all that apply.

-To become a fossil, an animal must remain buried for thousands or millions of years until it (and the layer around it) turns to rock. -Many fossils remain buried. We can only find them when they are exposed by erosion or excavation. -To become a fossil, an animal must be quickly and completely buried in ash or sediment before it has a chance to decompose.

Tiktaalik had a combination of fishlike and tetrapod-like characteristics. Which were the tetrapod-like characteristics? Select all that apply.

-a neck -interlocking ribs -flat head with eyes on top

Insects are the most diverse group of organisms, in terms of numbers of species, dominating terrestrial habitats. More than 30 orders of insects have been described, with the order Coleoptera being the largest. Classification is based on traits such as wings and mouthparts. All insects have a three-part body plan consisting of a head, thorax, and abdomen; three pairs of walking legs; and one or two pairs of wings. The chart below indicates defining characteristics for eight of the more than 30 orders of insects.

-a. hard forewings protect membranous hindwings -b. hindwings reduced to stabilizers -c. wings have scales -d. hairy wings -e. complete metamorphosis -f. incomplete metamorphosis -g. flies -h. "true bugs" -i. butterflies, moths -j. caddisflies

The body mass of the chimpanzee is approximately _______kg greater than the body mass of Australopithecus afarensis.

10

The ratio of brain volume to body mass of Homo ergaster is approximately _______.

14 cm3/kg

The brain volume of Homo sapiens is approximately _____ times as large as the brain volume of Australopithecus afarensis.

3

Identify the features that distinguish animals from organisms in other multicellular kingdoms. Select all that apply.

Animals are ingestive heterotrophs.

Which type of symmetry does each of the following animals display? Drag each picture to the appropriate bin.

Asymmetry: Sponge Radial Symmetry: Jelly, Hydra Bilateral Symmetry: Bobcat, Turtle, Snake, Octopus

Which species of hominin had a brain volume closest to the brain volume of the chimpanzee?

Australopithecus afarensis

Nematodes and arthropods are the largest ecdysozoan phyla. Which of the following statements are true? Select all that apply.

Both nematodes and arthropods must molt in order to increase in size. Arthropods possess an open circulatory system. Some nematodes are parasitic on humans. Both nematodes and arthropods possess an external covering, or cuticle. Arthropods are named for their jointed appendages

The earliest ancestors of about half of all extant animal phyla can be traced back to the __________ explosion.

Cambrian

Select the vertebrate taxon or taxa whose origin(s) involved duplication of Hox genes. Select all that apply.

Gnathostomes Craniates

What does the distance between two white horizontal lines on this graph represent?

an increase of 200 cm3 in brain volume

Which of the following statements describing hominin evolution is/are correct Select all that apply.

Homo sapiens is the only surviving member of a highly branched evolutionary tree of hominin species.

Which of the following best summarizes the results shown in the graph?

Crabs are more successful in preying on northern periwinkles.

Which feature of deuterostome development explains the formation of identical human twins?

Deuterostomes have indeterminate development.

Select the correct statement(s) about animal body plans. Select all that apply.

Development in all animals is determined by the unique family of Hox genes (or other similar homeobox genes).

What is the significance of the evolution of Hox gene clusters during vertebrate evolution?

Duplication of Hox genes made increased morphological complexity possible.

Select the correct statement(s) about invertebrate taxa. Select all that apply.

Ectoprocts lack a distinct head. Tapeworms lack a mouth and gastrovascular cavity. Rotifers are smaller than many protists.

Which structure is not an innovation that occurred during vertebrate diversification?

Exoskeleton

True or false? An organism that is radially symmetric has many well-developed head regions.

False

Lancelets and tunicates are two groups of chordates. Classify each statement as applying to lancelets, tunicates, both lancelets and tunicates, or neither. Drag each item to the appropriate bin.

Lancelets: - All chordate characters present in adults - Adults bury themselves into the sediment of the seafloor - Adults swim by the contraction of a series of muscles along the notochord Tunicates: - In adults, water enters through one siphon and leaves through another - Most chordate characters not present in adults - Larvae swim using the notochord, but adults may be sessile Both: - Adults feed with the aid of pharyngeal slits Neither: Adults swim using vertebral column

In the figure given below, the clade Deuterostomia is most closely related to which two main clades?

Lophotrochozoa and Ecdysozoa

All chordates share a set of derived characters during at least some part of their life. Drag the labels to their correct locations on the diagram of chordate characters below.

Notochord: - A flexible rod that runs along the anterior-posterior axis - May be associated with jointed skeleton Pharyngeal Clefts: - Grooves that separate pouches along the side of the pharynx - May develop into parts of the ear Pharyngeal Slits: - Openings to the outside of the body along the side of the pharynx - May develop into gill slits Dorsal, Hollow Nerve Cord - A bundle of nervous tissue running the length of the body - May develop into the brain and spinal cord Muscular, Post-Anal Tail: - A structure that contains muscles and extends past the anus - May be used to propel some species in water

What is the key difference between a coelom and a pseudocoelom?

Only a coelom is fully lined with mesoderm tissue.

Which structure can be used for feeding and gas exchange?

Pharyngeal gill slit

What evidence suggests that vertebrates are more closely related to echinoderms than are any other invertebrate phyla?

Shared DNA sequences

Select the correct statement(s) describing nematodes. Select all that apply.

Some nematodes play important roles in nutrient cycling. Nematodes lack a circulatory system and circular body wall muscles.

Based on the results shown in the graph, how has natural selection affected populations of flat periwinkles in the southern Gulf of Maine over the last century?

Southern populations of flat periwinkles have accumulated traits that make them less vulnerable than northern populations to predation by European green crabs.

What does the bed bug illustrate in regards to evolution?

Speciation can occur in just a few thousand years.

Some scientists are conducting research on the "saliva" of bed bugs. Which of the following is the most logical medical benefit from this research?

Using the anticoagulant to prevent blood clots in humans.

In a phylogenetic tree, a lineage that diverges from all other members of its group early in the evolutionary history of the group is described as

a basal taxon.

Which of the following is radially symmetrical?

a doughnut

Which of the following could be considered the most recent common ancestor of living tetrapods?

a sturdy-finned, shallow-water lobe-fin whose appendages had skeletal supports similar to those of terrestrial vertebrates

Which of the following chordates is least likely to look like other chordates?

adult tunicate

Which of the following groups contains members most closely associated with a wet or moist environment?

amphibians

Which of the following are thought to be most closely related to humans?

sea stars

Is this statement supported or not supported by the graph? Despite having a body mass similar to that of Homo sapiens, Homo neanderthalensis had a larger brain volume.

supported

Is this statement supported or not supported by the graph? The ratio of brain volume to body mass of Homo sapiens is larger than that of Homo ergaster.

supported

Which of the following clades contains the greatest number of animal species?

the bilaterians

Which of the following was probably the LEAST important factor in bringing about the Cambrian explosion?

the movement of animals onto land

Identify the dependent variable in this experiment.

the number of periwinkles killed by crabs

Identify an independent variable in this experiment.

the source of the periwinkles (northern or southern sites in the Gulf of Maine)

Why did the researchers present unshelled northern and southern periwinkles to northern and southern crabs in the second experiment?

to test if either population of periwinkles was unpalatable to either population of crabs

Why did the researchers set up four treatments?

to test whether the origin (northern site or southern site) of the crabs and periwinkles affected their interactions

Which of the following is NOT a diagnostic feature of the Chordata?

vertebrae

In the phylogenetic tree shown, which of the following are shared ancestral characters for members of the turtle-leopard group?

vertebral column; four limbs