Question

reasons for each suggestion. what shell shapes might be an advantage for gastro- pods that a. live clamped to wave - pounded rocks? b. move through sand or mud? activity 3 observe a live aquatic snail. materials • 5 - or 10 - gal established aquarium (sea - water or freshwater) • live snail (seawater or freshwater) • references on aquarium snails (optional) procedure 1. observe a live snail in an aquarium. a. carefully draw the snail and label its body parts. see fig. 6 - 1. look for the foot, mantle, operculum (if present), tentacles, siphon, eyes, and radula. because snail body plans vary, you may need to use references. b. describe the snail’s sensory structures, including the tentacles and eyes (if present). include these in your drawings. observe and record how the snail appears to use its sensory structures. determine what mechanical and chemical stimuli the snail responds to, such as food, touch, change in light intensity, or the presence of other organisms. c. observe the snail feeding. determine how it uses its mouth and radula to get food. design and perform ex - d. the patterns of the shells? 8. how do gastropods grow larger? how does their growth differ from the growth of bivalves? 9. what features of gastropod shells a. vary among individuals of the same species? b. do not vary among individuals of the same species? 10. suggest how shell shapes may reveal adaptations to their environment. give

Explanation:

1. Gastropods grow by adding new material to their shells and body over time. Their growth is different from bivalves as gastropods have a single - shelled or coiled shell and grow in a spiral pattern, while bivalves have two shells that grow by adding material along the edges.

9a. Among individuals of the same gastropod species, shell color, size, and some minor patterns may vary.
9b. The basic shape (e.g., coiled or conical), presence of certain structural features like spines or ribs in some species, and the general arrangement of whorls do not vary much among individuals of the same species.

1. Shell shapes can reveal adaptations. For example, a streamlined shell may be an adaptation for moving through water quickly in fast - flowing environments. A thick, heavy shell may be an adaptation for protection in wave - pounded areas.

Answer:

1. Gastropods grow by adding new material to shell and body, growing spirally; bivalves grow by adding material along shell edges.

9a. Shell color, size, minor patterns may vary.
9b. Basic shape, certain structural features, general whorl arrangement don't vary much.

1. Streamlined shell for fast - flowing water, thick shell for wave - pounded areas etc.