Question

19) All of the following are true about choanoflagellates except 19) A) They are sessile as adults. They live in aquatic habitats C) They are suspension feeders. D) They reproduce sexually E) They are protists. 20) What do all animals have in common? 20) A) They reproduce sexually B) They eat plants or other animals. C) They are multicellular. D) They move around. E) They sense and respond to their environment. 21) Which of the following characteristics would not fadlitate a sessile lifestyle? 21) A) abiity to secrete a poisonous coating B) asexual reproduction D) feeding on motile prey internal fertilization 22) In a habitat with only one abundant food source, which type of metamorphosis would you expect 22) an animal species to undergo? A) hemimetabolous metamorphosis 23) What is the function of the arthropod exoskeleton? 23) A) It provides protection and functions in locomotion. B) It has no well-established function.(Trilobites had an exoskeleton, and they went extinct.) C) It makes growth by molting possible. D) Because hard parts fossilize more readily than-do soft tissues, the presence of an exoskeleton has given arthropods a good fossil record. 24) Suppose you were a researcher choosing a model organism with which to study.animal genetics. 24) Which of the following characteristics would you not look for in your model orgarism? A) small size B) simple diet C) long life span D) abundant reproduction E) quick maturation 25) What major feature or features distinguish most of the wormlike phyla of protostomes from each 25) other? A) Their mouthparts and feeding methods vary B) Metamorphosis may be lacking, incomplete, or complete C) Their modes of locomotion differ-they burrow, swim, crawl, or walk D) They have a well-developed coelom and a tube-within-a-tube body plan 26) The anterior region of the crustaceans is called the 26) A) thorax B) cephalunm ) cephalothorax D)head A-4

Answer 1

19. A. They are sessile as adults. Chaonoflagellates have both free swimming and sessile characteristics.

20. C. They are multicellular. All the animals are multicellular in common.

21. C. Internal fertilization. In common sessile organisms undergo asexual reproduction.

23. A. It provides protection and functions in locomotion

24. C. Long life span

25. A&B. A. Their mouth parts and feeding methods vary. B. Metamorphosis may be lacking, incomplete or complete.

26. D. head