Bio 211 Final Exam Part 2

Which of the following statements best describes the overall process of descent with modification?

A trait present in an ancestral organism is modified by natural selection over time in descendants of that ancestor.

Which of the following statements about bilaterian animals is true?

All bilaterians are triploblastic (have three germ layers).

Which phylum is characterized by animals that have a segmented body?

Arthropoda

Which of the following statements about bryozoans (ectoprocts) is correct?

Bryozoans build reefs and have lophophores that extend through a hard exoskeleton.

Which of the following statements is correct with respect to the evolutionary relationship between chordates and invertebrates?

Chordates are more closely related to echinoderms than to arthropods

Select the correct statement(s) about invertebrate taxa.

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

The phylum Cycliophora includes tiny organisms that live in large numbers on the outsides of the mouthparts and appendages of lobsters. The feeding stage permanently attaches to the lobster via an adhesive disk and collects scraps of food from its host's feeding by capturing the scraps in a current created by a ring of cilia. The body is saclike and has a U-shaped intestine that brings the anus close to the mouth. Cycliophorans have a coelom, do not molt (though their host does), and their embryos undergo spiral cleavage.Based on the information provided, to which clades should cycliophorans belong?

Eumetazoa and Lophotrochozoa

Which of the following chordate groups include(s) humans?

Hominins Amniotes Gnathostomes

Which of the following statements about human evolution is correct?

Human evolution has occurred within an unbranched lineage.

You find what you believe is a new species of animal. Which of the following characteristics would enable you to argue that it is more closely related to a nematode than it is to an annelid?

It has a hemocoel.

In which of the following ways did the evolution of the jaw contribute to diversification of early vertebrate lineages?

It made additional food sources available.

The heartworms that can accumulate within the hearts of dogs and other mammals have a hemocoel, an alimentary canal, and an outer covering that is occasionally shed. To which phylum does the heartworm belong?

Nematoda

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

Porifera

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

Shared DNA sequences

What is believed to be the most significant result of the evolution of the amniotic egg?

Tetrapods are no longer tied to the water for reproduction.

Soft-shell crab is a prized dish in many ocean-side resorts. Which of the following statements provides the best explanation for the soft shell of the crabs?

The crab has just molted and the new exoskeleton has not yet hardened.

Which of the following statements correctly describes a characteristic of the phylum Platyhelminthes?

They are dorsoventrally flattened.

Which of these statements accurately describes a similarity between sharks and ray-finned fishes?

They have a lateral line that is sensitive to vibrations.

Which of the following statements is true of annelids?

They perform gas exchange across their skin.

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

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

Which of the following characteristics is shared by both cnidarians and flatworms?

a digestive system with a single opening

A land snail, a clam, and an octopus all share

a mantle

Vertebrates and tunicates share

a notochrod and a dorsal, hollow nerve cord

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 organisms is 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 characteristics is shared by a hagfish and a lamprey?

a well-developed notochord

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

adult tunicate

Which of the following structures can be found in the mesohyl of a sponge?

amoebocytes and spicules

The diagnostic feature of Chondrichthyes is __________.

an endoskeleton of cartilage

A marine biologist dredges up a small animal from the bottom of the ocean. It is uniformly segmented, with short, stiff appendages and soft, flexible skin. It has a complete digestive system and a closed circulatory system, plus multiple true coeloms. Based on this description, it may be determined that the animal must be a(n) __________.

annelid

Members of the phylum Mollusca __________.

are soft-bodied and often covered by a shell

Which of the following statements correctly describes one difference between nematodes and arthropods?

arthropods have an open circulatory system while nematodes do not have a circulatory system

Which of the following are the only extant animals that descended directly from dinosaurs?

birds

Which one of these mollusc groups is classified as suspension feeders?

bivalves

What structure is responsible for gas exchange in most spiders?

book lungs

Which of the following characteristics is exhibited by most hydrozoans?

both polyps and medusa forms

Jaws evolved __________.

by modification of the skeletal rods that previously supported the anterior pharyngeal slits

Which sponge cell is most structurally and functionally similar to the cnidocyte of a cnidarian?

choanocyte

The presences of which of the following anatomicals would best distinguish a gastropod from a chiton?

dorsal plates

Which of the following organisms uses a lophophore for feeding?

ectoproct

Which of the following organisms have lophophores?

ectoprocts and brachiopods

In vertebrates, the earliest known mineralized structures were associated with body parts involved in which of the following processes?

feeding

Which of the following feeding strategies is most likely to be used by aquatic organisms?

filter feeding

Which of the following adaptations led to an explosion in insect evolution?

flight

A hemocoel refers to a

functional body cavity lined by tissues derived from mesoderm and endoderm.

The water vascular system of echinoderms

functions in locomotion and feeding

Which of the following is a characteristic of cnidarians?

gastrovascular cavity

Which of the following groups includes the greatest number of organisms?

gnathostomes

Based on the highlighted (white) branches in the phylogenetic tree shown, which of the following labels refers to a paraphyletic group?

green algae

Unlike eutherians, both monotremes and marsupials

have some embryonic development outside the uterus

Which of the following characteristics allowed early gnathostomes to become successful predators?

ins stiffened with bone that increased maneuverability and improved gas exchange in the gills

What would the presence of a lophophore in a newly discovered species suggest about that organism?

it feeds by trapping food particles suspended in the water

As you are walking along a beach, you find an animal and believe that it belongs to the class Asteroidea. Which of the following characteristics would support your hypothesis that the animal is a sea star and not another type of echinoderm?

it has five or more appendages.

Which extant chordates are most like the earliest chordates in appearance?

lancelets

There are three major groups of mammals, categorized on the basis of their _____.

method of reproduction

If you brush your fingers along the tentacles of a sea anemone, which of the following are you most likely to find upon microscopic examination of your fingers?

nematocysts

Which of following reproductive strategies in mammals involves the mother laying eggs that hatch outside of her body?

oviparous reproduction

During chordate evolution, which of the following structures arose first?

paired fins

Some species of rotifers consist solely of females. Their method of reproduction is described as __________.

parthenogenesis

The crown-of-thorns sea star, Acanthaster planci, preys on the flesh of live coral. If coral animals are attacked by these sea stars, then what part of the coral actually provides nutrition to the sea star?

polyps

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

post-anal tail

If a tunicate's pharyngeal gill slits were blocked by a foreign object, which of the following processes would the organism have trouble performing?

respiring and feeding

Which of the following statements about hominin evolution is correct? As hominins have evolved, _____.

sexual dimorphism was significantly reduced

Which of the following senses would be most directly affected by removing or damaging an insect's antennae?

smelling

Which of the following groups of organisms has flagella associated with its method of feeding?

sponges

Which structure of the amniotic egg most closely surrounds the embryo?

the amnion

Which of the following characteristics do all insects exhibit?

they have an exoskeleton or cuticle

Which of the following statements describes sponges?

they have larvae that are motile and move via the motion of flagella

Which of the following characteristics of their exoskeletons is exhibited by both arthropods and molluscs?

they help retain moisture in terrestrial habitats

Which of the following statements describes how healthy corals appear brightly colored?

they host symbionts with colorful photosynthetic pigments

All of the following represent diagnostic features of chordates except for which one?

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

Why do large animals need specialized organs for gas exchange?

volume increases more rapidly than surface area as size increases