Which of the following animals is correctly matched with its type of skeleton? a. fly—endoskeleton b. earthworm—exoskeleton c. lobster—exoskeleton d. bee—hydrostatic skeleton

Verified step by step guidance

1. Identify the type of skeleton each animal has: Endoskeletons are internal skeletons found in vertebrates, exoskeletons are external skeletons found in many invertebrates, and hydrostatic skeletons are found in soft-bodied invertebrates.
2. Analyze option a: Flies are insects and insects have exoskeletons, which are hard outer structures made of chitin, not endoskeletons.
3. Analyze option b: Earthworms do not have a hard outer shell; instead, they have a hydrostatic skeleton, which uses fluid-filled compartments to provide structure.
4. Analyze option c: Lobsters are crustaceans, and like other arthropods, they have an exoskeleton made of chitin, which fits the description given.
5. Analyze option d: Bees, like flies, are insects and thus have exoskeletons, not hydrostatic skeletons.

Key Concepts

Types of Skeletons

Animals possess different types of skeletons that provide structure and support. The main types include endoskeletons (internal skeletons, like those in vertebrates), exoskeletons (external skeletons, like those in arthropods), and hydrostatic skeletons (fluid-filled cavities providing support, as seen in soft-bodied animals). Understanding these types is crucial for identifying the correct match between animals and their skeletal structures.

Endoskeleton

An endoskeleton is an internal support structure found in many vertebrates, including mammals, birds, and reptiles. It is composed of bone and cartilage, providing protection for internal organs and facilitating movement through muscle attachment. This type of skeleton allows for growth and flexibility, distinguishing it from exoskeletons, which must be shed and regrown as the organism grows.

Exoskeleton

An exoskeleton is a rigid external covering that provides support and protection to certain invertebrates, such as arthropods (e.g., insects, crustaceans). Made primarily of chitin, exoskeletons must be molted for the organism to grow, as they do not expand with the body. This type of skeleton offers advantages like protection from predators and environmental factors, but it also limits growth until the exoskeleton is shed.