1. Lobsters are invertebrates classified under the phylum Arthropoda along with shrimp, crabs, and insects. They have 10 legs, giving rise to the name decapod, that are jointed. Lobsters have no internal bones and instead have an exoskeleton that acts as body armor for protection. Lobsters have very poor eye sight, so they utilize two antennae as a sense of touch in order to gauge their surroundings.
Lobsters have two distinct claws for two purposes. One claw is the crusher claw, used for crushing shellfish and other prey, and the other is the pincher claw, which tends to be smaller and is used to tear food apart. Lobsters have “swimmerettes” which are found along the tail. In females, the tiny hairs on the swimmerettes act as an attachment site for eggs. (Lobster Institute, n.d.). Lobsters can regenerate legs, claws, and antennae. In some cases, if facing a threat, a lobster can self-amputate a claw to escape its predator. (Dog, n.d.)
Lobsters have three stomachs. The foregut, midgut and hindgut. The foregut contains the a set of grinding teeth so they can grind food into smaller particles. The food then travels to the midgut where more digestion takes place. Any material that is to large will pass to the hindgut and out through the anus.
Lobsters have twenty pairs of gills. These gills are made up of feathery like filaments and are protected in the gill chamber. The gills remove oxygen from the water and from air. Water passes through openings between the lobsters legs, over the gills and up toward the head. In order to flush debris out of the chambers the current will reverse.
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