Animals: Animal Development

A graduate student finds an organism in a pond and thinks it is a freshwater sponge. A postdoctoral student thinks it looks more like an aquatic fungus. How can they decide whether it is an animal or a fungus? 1. Determine whether it is unicellular or multicellular. 2. Figure out whether it is autotrophic or heterotrophic. 3. See if it reproduces sexually. 4. Look for cell walls under a microscope. 5. See if it is a eukaryote or prokaryote.

4. Look for cell walls under a microscope.

How many times has blastopore fate changed over the course of evolution? 1. 0 times 2. 1 time 3. 2 times 4. Multiple times, though the exact number is uncertain.

4. Multiple times, though the exact number is uncertain.

Which of the following is a feature of the "tube-within-a-tube" body plan in most animal phyla? 1. The outer tube consists of a hard exoskeleton. 2. The two "tubes" are separated by tissue that comes from embryonic endoderm. 3. The outer tube consists of digestive organs. 4. The mouth and anus form the ends of the inner tube.

4. The mouth and anus form the ends of the inner tube.

Both animals and fungi are heterotrophic. What distinguishes animal heterotrophy from fungal heterotrophy is that most animals derive their nutrition by ________. 1. consuming living, rather than dead, prey 2. using enzymes to digest their food 3. preying on animals 4. ingesting materials

4. ingesting materials

Which of the following is (are) unique to animals? 1. heterotrophy 2. the structural carbohydrate, chitin 3. flagellated gametes 4. nervous system signal conduction and muscular movement

4. nervous system signal conduction and muscular movement

Which tissue type or organ is not correctly matched with its germ layer tissue? 1. muscular: mesoderm 2. stomach: endoderm 3. skin: ectoderm 4. nervous: mesoderm

4. nervous: mesoderm

Gastrulation is the process that directly forms the _____. 1. organs 2. blastula 3. muscles 4. primary germ layers 5. central nervous system

4. primary germ layers

During embryological development, the anus forms before the mouth in _____. 1. earthworms 2. arthropods 3. flatworms 4. slugs 5. humans

5. humans

Many animals can be categorized as either protostomes and deuterostomes based on certain features of their embryonic development. Determine whether each of the following terms applies to only protostomes, only deuterostomes, both protostomes and deuterostomes, or neither. Drag each item to the appropriate bin. To review protostome and deuterostome characteristics, see the Hint -protosome -deuterostome -both -neither

-protostome: mouth from blastopore; spiral, determinate cleavage; coelom from solid masses of mesoderm -deuterostome: anus from blastopore; radial, inderterminate cleavage; coelom from folds of archenteron -both: triploblast -neither: diplobast

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 statements that are true. To review the germ layers and the terminology associated with body cavities, see the Hints. 1. A diploblast has no mesoderm. 2. The digestive tract of a coelomate functions as a coelom. 3. A pseudocoelom has the same functions as a true coelom. 4. In a coelomate, the tissue lining the inner side of the body cavity arises from the same germ layer as the lining of the digestive tract. 5. 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. 6. In a pseudocoelomate, the tissue lining the inner side of the body cavity arises from the same germ layer as the muscles. 7. An acoelomate triploblast has no endoderm.

1. A diploblast has no mesoderm. 3. A pseudocoelom has the same functions as a true coelom. 5. 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.

Which feature of deuterostome development explains the formation of identical human twins? 1. Deuterostomes have indeterminate development. 2. In deuterostomes, the blastopore becomes the anus. 3. Deuterostomes have radial cleavage.

1. Deuterostomes have indeterminate development.

Part complete Which of the following would you classify as something other than an animal? 1. choanoflagellate 2. sponge 3. coral 4.jellyfish

1. choanoflagellate

Part complete The last common ancestor of all animals was probably a _____. 1. flagellated protist 2. multicellular algae 3. multicellular fungus 4. unicellular chytrid

1. flagellated protist

The most ancient branch point in animal phylogeny is the characteristic of having _____. 1. true tissues or no tissues 2. diploblastic or triploblastic embryos 3. radial or bilateral symmetry 4. a body cavity or no body cavity

1. true tissues or no tissues

Which of the following statements comparing symmetry in sessile and swimming animals is most probable? 1. Radial symmetry occurs most frequently in animals that catch their prey by rapid swimming. 2. Bilaterally symmetric animals can be streamlined for swimming, but radially symmetric animals cannot. 3. Radial symmetry is more advantageous for active swimming than is bilateral symmetry. 4. Bilateral symmetry allowed animals to evolve nerves.

2. Bilaterally symmetric animals can be streamlined for swimming, but radially symmetric animals cannot.

Which of the following is radially symmetrical? 1. an automobile 2. a doughnut 3. a spoon 4. a submarine sandwich 5. a dog

2. a doughnut

An organism that exhibits a head with sensory equipment and a brain probably also ________. 1. is diploblastic 2. is bilaterally symmetrical 3. is segmented 4. has a coelom

2. is bilaterally symmetrical

The distinction between sponges and other animal phyla is based mainly on the absence versus the presence of... 1. a body cavity. 2. true tissues. 3. mesoderm. 4. a complete digestive tract. 5. a circulatory system.

2. true tissues.

Which of the following is NOT a characteristic of all animals? 1. They are eukaryotes. 2. They ingest their food. 3. They have tissues, organs, and organ systems. 4. They are all multicellular. 5. They are heterotrophic

3. They have tissues, organs, and organ systems.

The fact that choanoflagellates and collar cells of sponges resemble each other supports the inference that ________. 1. choanoflagellates and sponges evolved similar cell structures through convergent evolution 2. choanoflagellates are animals 3. choanoflagellates and sponges are sister groups 4. choanoflagellates are more closely related to sponges than they are to protists

3. choanoflagellates and sponges are sister groups

What was an early selective advantage of a coelom in animals? A coelom _____. 1. was a more efficient digestive system 2. allowed cephalization and the formation of a cerebral ganglion 3. contributed to a hydrostatic skeleton, allowing greater range of motion 4. allowed asexual and sexual reproduction

3. contributed to a hydrostatic skeleton, allowing greater range of motion

An important trend in animal evolution was cephalization. An animal is said to show cephalization when it _____. 1. has bilateral symmetry 2. is large 3. has an aggregation of sensory neurons at the anterior end 4. has tissue specialization 5. has a hard, outer covering

3. has an aggregation of sensory neurons at the anterior end

For the common ancestor of all the Bilateria, what was the fate of the blastopore? 1. deuterostomy (D) 2. neither (N) 3. protostomy (P) 4. It is impossible to tell from the data provided.

4. It is impossible to tell from the data provided.

Which type of symmetry does each of the following animals display? asymmetry, radial symmetry, bilateral symmetry -sponge -jelly -hydra -bobcat -turtle -octopus -snake

Asymmetry- sponge Radial symmetry- jelly, hydra Bilateral symmetry- bobcat, turtle, octopus, snake