Question 1

Which of the following correctly lists organisms from least complex in overall development to most complex?

Accepted Answer

This is the correct order of increasing complexity based on overall development. Sponges are the simplest organisms, followed by hydras, clams, lobsters, and finally tunicates, which are the most complex.

Question 2

Which of the following phyla is most closely related to echinoderms?

Accepted Answer

Chordata and Echinodermata both belong to the Deuterostomia clade, sharing similarities in embryonic development and molecular biology.

Question 3

Which of the following statements about tunicates indicates that these animals are chordates?

Accepted Answer

Tunicate larvae possess four unique features of chordates: dorsal hollow nerve cord, post-anal tail, pharyngeal slits, and notochord.

Question 4

You find a small, elongated animal embedded in the sand with one end sticking out. Among other things, it has segmental musculature, a coelom, a notochord, and a complete digestive tract with an anus located partway down the body. This animal is

Accepted Answer

The presence of a notochord and a complete digestive tract with an anus located partway down the body are both characteristics of chordates. Additionally, the presence of segmental musculature and a coelom are also features found in chordates. Therefore, the animal is most likely a chordate, and not an annelid or a larval echinoderm.

Question 5

Complete metamorphosis is considered to occur in a species

Accepted Answer

Complete metamorphosis is characterized by four distinct stages: egg, larva, pupa, and adult. The pupa stage is a crucial separating stage between the larval and adult stages in which the organism undergoes a significant transformation, making C the best choice. The other options listed (A, B, and D) do not necessarily distinguish complete metamorphosis from incomplete metamorphosis since they can occur in both. For example, some insects that undergo incomplete metamorphosis have different diets in the nymphal and adult stages, and some have wings in the adult stage but not in the nymphal stage.

Question 6

The traits that are unique to insects and have probably contributed to their diversity and success include

Accepted Answer

Flight, short generation times, and complex life cycles including complete metamorphosis are all unique traits to insects that have contributed to their diversity and success. Flight allows insects to rapidly colonize new areas and escape predators. Short generation times allow for rapid adaptation to changing environments. Complex life cycles with complete metamorphosis allow insects to exploit different resources at different life stages, and reduce competition between different life stages. The other options may be partially correct, but they do not encompass all the unique traits of insects that have contributed to their diversity and success.

Question 7

According to the "new" revised phylogeny based on genetic analyses, annelids are a member of the Lophotrochozoa and are most closely related to which of the following groups?

Accepted Answer

According to the revised phylogeny based on genetic analyses, annelids are a member of the Lophotrochozoa and are most closely related to molluscs.

Question 8

Which of the following statements is true?

Accepted Answer

This is the only option that correctly identifies sponges as having no true tissues and being filter feeders, while also correctly identifying cnidarians as having true tissues and a gastrovascular cavity. The other options have incorrect information about these phyla or mix up information about different phyla.

Question 9

According to recent genetic research, the complexity of an organism

Accepted Answer

Recent genetic research suggests that the complexity of an organism is not simply determined by the number of genes, but rather by how those genes are used and regulated. This means that even simpler organisms with fewer protein-coding genes may still exhibit a high level of complexity if those genes are used in complex and sophisticated ways.

Question 10

Which of the following features is unique to chordates?

Accepted Answer

Only chordates have a notochord, which is a flexible supportive rod that runs along the length of their body and defines their dorsal-ventral axis. Bilateral symmetry, a coelom, and a complete digestive tract with an anus are present in many other animal phyla.

Question 11

Which of the following is an invertebrate chordate?

Accepted Answer

Lancelets are invertebrate chordates, meaning they have a notochord and other characteristic features of chordates but lack a vertebral column. The other answer choices (snakes, sharks, and sea urchins) are not invertebrate chordates but rather vertebrates or echinoderms.

Question 12

The symmetry of echinoderms generally includes

Accepted Answer

Echinoderms, such as starfish and sea urchins, exhibit bilateral symmetry during their larval stage and transition to radial symmetry as adults.

Question 13

Invertebrate diversity contributes to all of the following except

Accepted Answer

Invertebrate diversity does not contribute significantly to bioremediation - the use of living organisms to clean up contaminated areas.

Question 14

The insect body plan includes many groups of serially repeated units. For example, there are typically three pairs of legs, one on each of the three segments of the thorax. Which of the following options best describes how these pairs of legs develop and evolve?

Accepted Answer

The insect body plan develops in a modular fashion, which means that a genetic change could alter the development of one pair of limbs without noticeably changing the rest of the insect's body plan. This allows for greater flexibility in the evolution of specific body parts without disrupting the overall body plan.

Question 15

The flexible, longitudinal rod that is located between the digestive tract and the nerve cord in chordates is called the

Accepted Answer

The flexible, longitudinal rod that is located between the digestive tract and the nerve cord in chordates is called the notochord. The notochord provides support and helps to define the body axis.

Question 16

To be characterized as a chordate, an organism must

Accepted Answer

To be characterized as a chordate, an organism must display each of the four key characteristics of the chordates at some point in the life cycle. These key characteristics include having a notochord, dorsal hollow nerve cord, pharyngeal slits or pouches, and a post-anal tail. A backbone is not a requirement for being a chordate, as some chordates lack backbones at certain points in their life cycle.

Question 17

Which of the following exhibits bilateral symmetry?

Accepted Answer

Butterflies have bilateral symmetry, meaning their left and right sides are mirror images of each other.

Question 18

Which of the following is a unique feature of echinoderms?

Accepted Answer

A water vascular system is a unique and defining feature of echinoderms. It is a network of canals and tube feet that are used in locomotion and feeding. Bilateral symmetry and radial symmetry are not unique to echinoderms as they are found in other animal groups. Deuterostome pattern of development is a characteristic shared by all echinoderms and some other animal groups as well.

Question 19

Traditional animal phylogenetic trees and the most recent molecular phylogenetic trees have many similarities. Which is a feature of the recent trees that was not present in the traditional phylogeny?

Accepted Answer

The grouping of nematodes and arthropods into a clade called the Ecdysozoa is a feature of molecular phylogenetic trees that was not present in traditional animal phylogenetic trees.

Question 20

Different species of brittle stars (echinoderms)have different feeding mechanisms. When a species of brittle star feeds by using tentacle-like appendages to capture large food particles, it is using which of the following feeding mechanisms?

Accepted Answer

Suspension feeding is a feeding mechanism in which organisms use specialized structures to capture small food particles from the surrounding water. In the case of brittle stars that use tentacle-like appendages to capture large food particles, they are not using a radula (a tongue-like organ with small teeth used for scraping food), clawlike appendages, or nectar feeding (feeding on sugary plant fluids).

Quiz 18: The Evolution of Invertebrate Diversity