All animals are ______________________.

Animal cells lack _____________________

Worms and insects are both ____________________.

The __________________ in a chordate embryo has nerves branching from it at intervals.

An animal species that has evolved the adaptation of changing color with the seasons likely produces gametes with _____________ genes

The ____________ system delivers metabolic wastes to the excretory system for processing and elimination.

Animals rely on ______________ feedback mechanisms to maintain homeostasis.

Biologists have hypothesized that echinoderms are closely related to ______________ because both groups are deuterostomes.

The hollow nerve cord develops from the ____________.

A lobster is considered bilaterally symmetrical because its __________ sides are mirror images of each other.

All vertebrates are ______________.

The ____________ side of an animal is its upper side.

Natural selection favors the evolution of any behavior that is adaptive and influenced by _______.

A cat that runs into the kitchen when it hears a can being opened shows that its behavior has been modified through ______________.

Most bats sleep during the day and hunt or forage at night. This activity pattern in bats is an example of ______________.

Unlike a vertebrate chordate, a nonvertebrate chordate adult lacks ________________.

___________ are not considered a clade because the organisms all lack a particular characteristic instead of sharing one.

Animals gather information using special cells called _________.

The fact that appendages appear in several different vertebrate and invertebrate phyla indicates that the formation of __________ has evolved more than once.

The _______ of animals is based on scientists' current understanding of the evolutionary history of living species.

Different species within a phylum all have the same basic ___________.

Fishermen often claim that fish are more likely to strike at bait when it is raining because the fish react to the raindrops on the surface of the water as if they were potential food. This response is considered a behavior because the fish are responding to a stimulus in their _______________________.

Unlike learned behavior, a(an) ____________________ behavior is performed correctly the first time an animal attempts it.

Baby sea turtles hatch underground, automatically dig upward toward the sky, and scurry toward the waves. This is an example of ________________ behavior.

__________________ in newborn animals is considered a complex behavior because it involves both innate and learned behavior.

Behavioral cycles that repeat daily are called _________________________.

The smaller worker ants on the leaf serve as lookouts while the larger ant carries the leaf back to the ant colony’s fungus farm. This is an example of ____________________ behavior.

Apes shake branches, make arm gestures, and vocalize loudly when competing with one another. These behaviors are manifestations of ____________________.

If an animal produces a sound and another animal obtains information by hearing the sound, the two animals are engaging in a form of ____________________.

Female silkworm moths release a chemical messenger called bombykol to attract male moths of the same species. Bombykol is a(an) ____________________.

Look at the illustration in Figure 25–2. This animal can be classified as

Look at the illustration in Figure 25–3. Which of the following internal characteristics would you expect this animal to have?

Look at the illustration in Figure 25–4. Do you think that the bud on the side of the adult hydra is an embryo? Why?

Look at the jellyfish in Figure 25–6. How many planes of symmetry could you draw through this animal?

Study the illustration in Figure 29–2. These baby swans likely imprinted on their mother after they hatched because she

Organisms that must obtain nutrients and energy by eating other organisms are

Which of the following correctly describes the major types of animals?

Nerves branch in intervals from which of the following structures in a chordate embryo?

Fewer than 5 percent of all animal species have

Homeostasis is a

All animals eat to obtain

Muscles work together with a support structure called a

When an animal’s environment changes, sexual reproduction improves a species’ ability to

One advantage of asexual reproduction is that animals can

to maintain homeostasis, land animals that hunt and feed in salt water

The presence of legs or other limbs indicates that the animal is

In an animal that is bilaterally symmetrical, which two halves mirror each other?

An animal that has body parts that extend outward from its center shows

A coelom is a body cavity

A blastula is

Four types of animal tissues are

Which of the three germ layers in animal embryo gives rise to muscles and much of the circulatory, reproductive, and excretory systems?

The lungs develop from the

Which of the following pairs of phyla are segmented protostomes with true coeloms?

Which of the following is a node that you would expect to find on the cladogram for animals?

Body plans evolve as adaptation

Which of the following behaviors is not necessary for an animal to reproduce?

Which of the following behaviors must be learned from another animal?

Young sea turtles head for the ocean immediately after they hatch. This behavior is most likely

you could conclude that a behavior is innate rather than learned if you showed that

Aquarium fish often swim to the water’s surface when a person approaches. Their behavior has probably formed through

When people first move into an apartment near railroad tracks, they are awakened at night each time they hear a train go by. Which of the following responses to the sound of the train would be the result of habituation?

The Fischer’s lovebird builds its nests with long strips of vegetation that it cuts with its beak. All lovebirds know how to punch holes with their beaks. But young birds must practice to find the arrangement of holes that cuts a strip suitable for nest building. This suggests that nest-building behavior in Fischer’s lovebirds is

Imprinting is a form of behavior that

The ability of salmon to recognize their home stream at spawning time is an example of

After a young duck imprints on a nonliving model of an adult duck, the young duck will

The appearance of fireflies at dusk is an example of a circadian rhythm because it

Entering a sleeplike state during winter to survive when resources are scarce is a type of behavioral cycle called

Body temperature of a ground squirrel changes over the course of a year as shown in Figure 29–3. A decline in body temperature indicates times when the ground squirrel has become dormant to conserve energy in response to scarce resources and cold temperatures. Based on the graph, the squirrel was dormant the most during which months?

During migration, animals undertake a

The theory that helping family members survive increases the chances that some of one's genes will be passed along to offspring is called

The members of a society

It is advantageous for grazing mammals to gather in groups because groups

In some species of balloon flies, males spin balloons of silk and carry them while flying. If a female approaches one of the males and accepts his balloon, the two will fly off to mate. This type of behavior is an example of

Cephalopods such as squid and octopi can communicate by changing skin colors and sometimes even skin patterns. This type of communication is an example of a

Many cat species mark their territory by rubbing glands on their faces against a surface such as a tree trunk. This form of communication relies on a

What would be the best way for an animal to communicate its ownership of an area’s resources to other individuals that visit the area when the owner is not around?

Nocturnal animals that have a poorly developed sense of smell are most likely to communicate by