Lab Practical Hydra Labeling Flashcards

Cnidaria Phylum

• Includes diverse organisms such as hydras, jellyfish, and corals, characterized by their specialized cells called cnidocytes.

Medusa Form

• One of the two body forms in cnidarians that is free-floating; it resembles an umbrella shape and is typically associated with jellyfish.

Polyp Form

• The stationary and attached body form in cnidarians; it has a tubular shape and is often found in corals and sea anemones.

Tentacles

• Armed appendages that surround the mouth; used for capturing prey and defense.

Mouth/Anus

• A single opening in cnidarians that serves both feeding and waste expulsion.

Body Column

• The elongated, central part of the polyp that connects the tentacles to the basal disc.

Bud

• A reproductive structure that can develop into a new individual, found on the side of a polyp.

Basal Disc

• The structure that anchors the polyp to a substrate, allowing it to remain attached.

Mesoglea

• A jelly-like substance that separates the two cell layers (epidermis and gastrodermis) in cnidarians; provides support and buoyancy.

Gastrovascular Cavity

• A central cavity where digestion occurs; it transports nutrients throughout the organism.

Gastrodermis

• The inner layer of cells that lines the gastrovascular cavity, involved in digestion and nutrient absorption.

Epidermis

• The outer cell layer of cnidarians that provides protection and is involved in sensation.

Nutritive Muscular Cells

• Specialized cells in the gastrodermis that aid in digestion and help move food through the gastrovascular cavity.

Gland Cells

• Cells that secrete enzymes and substances aiding in digestion and other functions within the gastrovascular cavity.

Cnidocytes

• Specialized cells that contain nematocysts (stinging structures), used for capturing prey and defense against predators.