Which of the following is (are) unique to animals?
nervous system signal conduction and muscular movement
Both animals and fungi are heterotrophic. What distinguishes animal heterotrophy from fungal heterotrophy is that most animals derive their nutrition by ________.
ingesting materials
What do animals ranging from corals to monkeys have in common?
presence of Hox genes
The last common ancestor of all animals was probably a _____.
flagellated protist
Which of the following genetic processes may be most helpful in accounting for the Cambrian explosion?
gene duplication
Whatever its ultimate cause(s), the Cambrian explosion is a prime example of _____.
adaptive radiation
asymmetry
sponge
radial symmetry
hydra, jelly
bilateral symmetry
bobcat, turtle, snake, octopus
Animal tissues develop from embryonic germ layers. Triploblastic animals have three germ layers (ectoderm, mesoderm, and endoderm) and three basic body plans related to body cavities (acoelomate, pseudocoelomate, and coelomate).
Select the three statement
A diploblast has no mesoderm.
A pseudocoelom has the same functions as a true coelom.
In a coelomate, the tissue lining the inner side of the body cavity arises from the same germ layer as the tissue lining the outer side of the body cavity.
protostome
mouth before blastopore.
spiral, determinate cleavage.
coelom from solid masses of mesoderm.
deuterostome
anus before blastopore.
radial, indeterminate cleavage.
coelom from folds of archenteron.
both protostome and deuterostome
triploblast
neither protostome and deuterostome
diploblast
Gastrulation is the process that directly forms the _____.
primary germ layers
An important trend in animal evolution was cephalization. An animal is said to show cephalization when it _____.
has an aggregation of sensory neurons at the anterior end
When a scientist describes the "body plan" of a phylum, he or she is implying that ________.
the body shapes we see now have been more successful than others in the past
The distinction between sponges and other animal phyla is based mainly on the absence versus the presence of
true tissues.
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.
Identify the features that distinguish animals from organisms in other multicellular kingdoms.
Identify the features that distinguish animals from organisms in other multicellular kingdoms.
Select the correct statement(s) about animal body plans.
Development in all animals is determined by the unique family of Hox genes (or other similar homeobox genes).
What is the key difference between a coelom and a pseudocoelom?
Only a coelom is fully lined with mesoderm tissue.
Which feature of deuterostome development explains the formation of identical human twins?
Deuterostomes have indeterminate development.
Which of the following is characteristic of the phylum Platyhelminthes?
They are dorsoventrally flattened.
Members of the phylum Mollusca _____.
are soft-bodied and often covered by a shell
Which of the following is true of annelids?
They perform gas exchange across their skin.
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 flatworm than it is to a roundworm?
It has no coelom.
Which of the following organisms would you expect to have the largest surface-area-to-volume ratio? Assume that all of the following are the same total length.
a platyhelminth
Large animals need specialized organs for gas exchange because ________.
volume increases more rapidly than surface area as size increases
Which of the following changes would lead to an increase in surface-area-to-volume ratios?
increasing the number of layers in the chloroplasts of plants
What structure is responsible for gas exchange in most spiders?
book lungs
Nematodes and arthropods both ________.
grow in conjunction with shedding of their exoskeleton
Arthropod exoskeletons and mollusc shells both ________.
help retain moisture in terrestrial habitats
All insects ________.
have segmented bodies and an exoskeleton
The heartworms that can accumulate within the hearts of dogs and other mammals have a pseudocoelom, an alimentary canal, and an outer covering that is occasionally shed. To which phylum does the heartworm belong?
Nematoda
Compared to insects with incomplete metamorphosis, insects with complete metamorphosis ________.
use a greater variety of food resources
The increase in plant species diversity allowed which of the following events?
a massive increase in species diversity of insects
Which of the following are thought to be most closely related to humans?
sea stars.
(Humans and sea stars are deuterostomes)
Select the correct statement(s) about invertebrate taxa.
1. Rotifers are smaller than many protists.
2. Ectoprocts lack a distinct head.
3. Tapeworms lack a mouth and gastrovascular cavity.
Select the correct statement(s) describing nematodes
1. Nematodes lack a circulatory system and circular body wall muscles.
2. Some nematodes play important roles in nutrient cycling
What evidence suggests that vertebrates are more closely related to echinoderms than are any other invertebrate phyla?
Shared DNA sequences
Which of the following is NOT a diagnostic feature of the Chordata?
vertebrae
Which extant chordates are postulated to be most like the earliest chordates in appearance?
lancelets
Jaws evolved _____.
by modification of the skeletal rods that previously supported the anterior pharyngeal gill slits
The diagnostic feature of Chondrichthyes is _____.
an endoskeleton of calcified cartilage
Which of these statements accurately describes a similarity between sharks and ray-finned fishes?
They have a lateral line that is sensitive to vibrations.
Jaws first occurred in which extant group of fishes?
chondrichthyans
Most members of which of the following groups are most closely associated with a wet or moist environment?
amphibians
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
Listed below are four adaptations of terrestrial vertebrates. Which is a characteristic only of truly terrestrial animals with no need to return to water at any stage of the life cycle?
amniotic eggs
(in contrast to the shell-less eggs of amphibians, amniotic eggs (of most reptiles, and a few mammals) have a shell that retains water and can be laid in a dry place.)
Which structure of the amniotic egg most closely surrounds the embryo?
the amnion
Which characteristic is common to all the modern representatives of all major reptilian lineages (turtles, lepidosaurs, crocodilians, and birds)?
presence of a notochord
Which of the following are the only extant animals that descended directly from dinosaurs?
birds
During chordate evolution, what is the sequence (from earliest to most recent) in which the following structures arose?
paired fins, jaws, swim bladder, amniotic egg, four-chambered heart
At one time, birds held the same taxonomic rank as Reptilia and Mammalia. Now, however, they are considered as part of the reptile clade. Without this change, ________.
Reptilia would be paraphyletic
There are three major groups of mammals, categorized on the basis of their _____.
method of reproduction
(Monotremes are egg-laying mammals, marsupials are pouched mammals, and eutherians are placental mammals.)
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?
location of the eyes at the front of the head
What group of mammals have (a) embryos that spend more time feeding through the placenta than the mother's nipples, (b) young that feed on milk, and (c) a prolonged period of maternal care after leaving the placenta?
Eutheria
Which of the following represents the strongest evidence that two of the three middle ear bones of mammals are homologous to certain reptilian jawbones?
These bones can be observed to move from the developing jaw to the developing middle ear in mammalian embryos.
Unlike eutherians, both monotremes and marsupials _____.
have some embryonic development outside the uterus
Which of the following statements about the geographic distribution of marsupials is accurate?
they occur in Australia and the Americas
Which clade does not include humans?
diapsids
Which of the following chordate groups include(s) humans?
1. Hominins
2. Gnathostomes
3. Amniotes
Select the vertebrate taxon or taxa whose origin(s) involved duplication of Hox genes.
1. Craniates
2. Gnathostomes