BIO 20: MARINE INVERTEBRATES ASSIGNMENT I (35 POINTS)
Goal: Describe each phylum of invertebrates so that you are able understand the general differences among the
many phyla. Focus on the major characteristics that cause each phylum of animals to be different from the other
phyla. These differences have caused scientists to place animals into such groups in the first place.
Instructions: Use Ch. 7 in your textbook to find the listed information about each phylum of invertebrates. Also,
visit our course website to view pictures of organisms that fall under each phylum. Looking at pictures while
learning about the different phyla will help you remember them. Print out two copies of the completed assignment.
Assignment must be typed. Turn in one copy on the due date and bring the other to class because we will be going
over it during lecture. This will be your study guide for this portion of the exam.
Phylum Porifera: (5 pts)
1. State the animals that fall within this phylum. (1 pt)
2. Briefly describe the general body plan of these animals by stating: a) whether they are simple or complex, and
b) if they have true tissues, c) whether they live as colonies or individually. Also, state how these animals feed.
(3 pt)
3. Why is this phylum the first one that we discuss? (1 pt)
Phylum Cnidaria: (6 pts)
1. State the animals that fall within this phylum. (1 pt)
2. Briefly describe the general body plan of these animals by stating: a) if they have true tissues and b) the type of
body symmetry they have. (2 pt)
3. State and describe the two basic body forms of cnidarians. (2 pt)
4. State and describe the structures that cnidarians use and discharge to capture and handle food. (1 pt)
Phylum Ctenophora: (4 pts)
1. State the common name of the animals that fall within this phylum. (1 pt)
2. Briefly describe the general body plan of these animals by stating: a) the type of body symmetry do they have
and b) how do they swim and what they use to swim. (2 pt)
3. State and describe the structures that ctenophores use to capture and handle food. (1 pt)
Phylum Platyhelminthes: (4 pts)
1. State the common name of animals that fall within this phylum. (1 pt)
2. Briefly describe the general body plan of these animals by stating: a) if they have true tissues, b) if they have
organs, and c) the type of body symmetry they have. (3 pt)
Phylum Annelida: (4 pts)
1. State the common name of the animals that fall within this phylum. (1 pt)
2. Briefly describe the general body plan of these animals by describing what segmentation is. (1 pt)
3. State the class of animals that include the marine annelids in this phylum. State how this specific group is
adapted to live in the marine environment. (2 pt)
Phylum Mollusca: (12 pts)
1. State the familiar animals that fall within this phylum. (1 pt)
2. Briefly describe the general body plan of these animals by describing the five basic structures that most
molluscs have. (5pt)
3. State and briefly describe the three major classes of molluscs (state the familiar animals that fall within each
class and list general characteristics that animals within each class possess). (6 pt)
BIO 20: MARINE INVERTEBRATES ASSIGNMENT II (35 POINTS)
Goal: Describe each phylum of invertebrates so that you are able understand the general differences among the
many phyla. Focus on the major characteristics that cause each phylum of animals to be different from the other
phyla. These differences have caused scientists to place animals into such groups in the first place.
Instructions: Use Ch. 7 in your textbook to find the listed information about each phylum of invertebrates. Also,
visit our course website to view pictures of organisms that fall under each phylum. Looking at pictures while
learning the different phyla will help you remember them. Print out two copies of the completed assignment.
Assignment must be typed. Turn in one copy on the due date and bring the other to class because we will be going
over it during lecture. This will be your study guide for this portion of the exam!
Phylum Arthropoda: (10 pts)
1. State the familiar animals that fall within this phylum. (1 pt)
2. Comment on the size (number of species) within this phylum. (1 pt)
3. Briefly describe the general body plan of these animals by stating: a) the type of body symmetry they have, b)
they type of appendages they have, and c) the type of “skeleton” they have. Also describe molting. (4 pt)
4. State the subphylum of animals that include the marine arthropods. Also, state the animals that fall within this
subphylum. Lastly, state how this specific group is specialized for living in the water. (3 pt)
5. Read about all the small crustaceans. Briefly describe what a barnacle is and how it lives and feeds. (1 pt)
Phylum Echinodermata: (12 pts)
1. State the familiar animals that fall within this phylum. (1 pt)
2. Briefly describe the general body plan of these animals by stating: a) the type of symmetry they have, b) the
type of “skeleton” they have, and c) the type of vascular system they have. (3 pt)
3. State the common name(s) of animals that fall under class Asteroidea, class Ophiuroidea, class Echinoidea,
class Holothuroidea. Also briefly state the general characteristics differentiating each class. (8 pt)
Phylum Hemichordata: (3 pts)
1. State the common name of the animals that fall within this phylum. (1 pt)
2. Briefly describe what these animals look like. (1 pt)
3. Describe why hemichordates are considered a “missing link”. (1 pt)
Phylum Chordata: (10 pts) (Made up of 3 subphyla, two of which lack a true backbone)
1. State the four characteristics that all chordates have in common. (4 pt)
2. State the two subphyla, within this phylum, that lack a true backbone. (2 pt)
a) State the animals that fall within each subphylum. (2 pt)
b) Briefly describe what animals in each subphylum look like. (1 pt)
c) Why do tunicates still fall under phylum Chordata, when as adults they do not possess all of the chordate
traits? (1 pt)