Concept explainers
Test Your Understanding
1. Which of the following is not a shared derived character of echinoderms? (a) water vascular system (b) notochord (c) tube feet (d) pentaradial symmetry in adult (e) endoskeleton of calcium carbonate plates and spines
Introduction: Animal phylogeny is the rapidly changing field for biologists. Even if the members of the animal kingdom are incredibly diverse, there are various animals sharing certain features that differentiate them from other organisms of the kingdom. The most highly derived body plan among all animals of the animal kingdom is echinoderm. Echinoderms are the animals that have no terrestrial or freshwater representatives and these animals belong to marine habitat.
Answer to Problem 1TYU
Correct answer: The presence of notochord is not a shared derived character of echinoderms. Hence, the correct answer is option (b).
Explanation of Solution
Reason for the correct answer:
The shared derived characters of echinoderms are as follows:
- Presence of water vascular system.
- Presence of numerous tiny tube feet.
- Presence of endoskeleton, ciliated epidermis, and thin covering.
- The adults of echinoderms exhibit pentaradial symmetry.
The presence of notochord is one of the characters of chordates. Some of the chordates have notochord during some time of their developmental cycle, whereas some chordates have notochord during their whole life time like vertebrates. It is not the shared derived character of echinoderms.
Option (b) is given as “notochord”.
The presence of notochord is not a shared derived character of echinoderms. Hence, the correct answer is option (b).
Reasons for the incorrect answers:
Option (a) is given as “water vascular system”.
The unique structural derived character of echinoderms is the presence of a network of fluid-filled canals and chambers called water vascular system. Hence, option (a) is incorrect.
Option (c) is given as “tube feet”.
The presence of numerous tiny tube feet is one the structural unique character of echinoderms. Hence, option (c) is incorrect.
Option (d) is given as “pentaradial symmetry in adult”.
The echinoderm adult exhibits pentaradial symmetry and the larval form exhibits bilateral symmetry. Hence, option (d) is incorrect.
Option (e) is given as “endoskeleton of calcium carbonate plates and spines”.
The presence of endoskeleton, ciliated epidermis, and thin covering is the unique feature of echinoderm. The endoskeleton of echinoderms consists of calcium carbonate (CaCO3) spines and plates. Hence, option (e) is incorrect.
Hence, options (a), (c), (d), and (e) are incorrect.
The presence of notochord is not a shared derived character of echinoderms.
Want to see more full solutions like this?
Chapter 32 Solutions
Mindtap Biology, 1 Term (6 Months) Printed Access Card For Solomon/martin/martin/berg's Biology, 11th
- Test Your Understanding 11.EVOLUTION LINK Discuss the relationships among the echinoderms and chordates, describing shared derived characters that support grouping these animals as deuterostomes.arrow_forward3 (8.B) A student collected the animal shown below on a field trip. The student used a dichotomous key and a microscope to classify the animal. Step Characteristic Identification Go to 2 la Possesses segmentation 1b Lacks segmentation 2a Has an exoskeleton with jointed appendages Has no exoskeleton, unjointed appendages (if any present), and a segmented worm- Go to 3 Phylum Arthropoda 2b Phylum Annelida like body; is possibly in a tube (if in a tube, may have tentacles) Possesses a foot, a radula, arms, and/or За a shell Phylum Mollusca Lacks all of the above and is dorsoventrally 3b Phylum Platyhelminthes flattened How should this animal be classified? A Arthropoda C Mollusca B Annelida D Platyhelminthes silominA istockphoto.com/Nancy Nehringarrow_forwardMatch the following:(a) Operculum (i) Ctenophora(b) Parapodia (ii) Mollusca(c) Scales (iii) Porifera(d) Comb plates (iv) Reptilia(e) Radula (v) Annelida(f ) Hairs (vi) Cyclostomata and Chondrichthyes(g) Choanocytes (vii) Mammalia(h) Gill slits (viii) Osteichthyesarrow_forward
- 1. What type of symmetry is displayed in the arthropods? 2. Do the arthropods exhibit cephalization?arrow_forwardEndoskeletons: a. protect internal organs and provide structures against which the force of muscle contraction can work. b. differ from exoskeletons in that endoskeletons do not support the external body. c. cannot be found in echinoderms. d. are composed of cartilaginous structures that form the skull. e. compose the arms and legs.arrow_forwardTest Your Understanding 4.Which of the following characteristics is/are associated with amphibians? (a) amnion (b) placoid scales (c) heart with two complete ventricles (d) swim bladder (e) metamorphosisarrow_forward
- Page < 3 of 7 4. Using forceps or tweezers, gently pull the 4th or 5th pereiopod to examine its motion. Do so without tearing the appendage off from the body. How would you describe its maneuverability? What are the limitations to motion of these walking legs? Given their small size and limited capacity for muscle attachment, how is it that this animal can use these appendages for motion? 5. Describe the structural differences between the pleopods and the pereiopods up the prawn. What hypothesis can you make regarding the functional use of pleopods by comparison? Pleopods of prawns are far larger in comparison to body size then crayfish (see drawings below). What might this tell you about their use between the two closely related animals? 6. Compare the overall body plan of the prawn to that of an insect like a grasshopper (see drawings below). Provide a complete side-by-side analysis of the two groups that would include body regions, and appendages. Focus your comparison on how the…arrow_forwardCnidocytes (a) are characteristic of sponges (b) are found among cells lining the gastrovascular cavity (c) contain stinging organelles (d) are lined with mesoderm (e) have two main shapesarrow_forwardWhy do you believe squid received the name cephalopod, which means head-foot? What distinguishes the tentacles from the grasping arms? What do the tentacles' specialized ends look like? Explain all in three paragraphs.arrow_forward
- Members of Chondrichfhyes are thought to be descended from fishes that had. a cartilaginous skeleton a bony skeleton mucus glands slime glandsarrow_forward1.The Order Squamata consists of 3 sub orders.Why are these Suborders so different-give at least 2 distinctive characteristics of each. 2.Why are Tuataras not grouped together with lizards?what is the morphological character that separates them? 3.How the reptile eggs differ from amphibian eggs?Why is this important?arrow_forwardGive at least 10 exoskeletons found in animals, source, its description and state their embryonic origin. (Explain in 1-3 sentences) (Use the table)arrow_forward
- Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage LearningBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxBiology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781337408332Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage Learning
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning