Educational Lobster Video- External body segments & Appendages

Summary

In this engaging lobster dissection, the viewer is guided through the external anatomy of a live lobster, affectionately named 'Larry.' Key features such as the large claws, rostrum, antennae, compound eyes, and various body segments are explored, highlighting their structure and function. The lobster’s mouthparts, including maxillae, mandibles, and maxillipeds, are discussed in detail, showing how they assist in feeding. The video also covers the lobster's walking and swimming legs, sensory bristles, and the unique articular membrane, offering fascinating insights into how these adaptations help the lobster survive in its environment.

Takeaways

• 😀 The lobster's large claws, called Keila pens, serve both defense and feeding purposes, with one designed for crushing and the other for tearing food.
• 😀 The sharp, pointy rostrum protects the lobster's eyes and aids in defense, having small spines for additional protection.
• 😀 Lobsters have two pairs of antennae: one larger for tactile sensing and another smaller for sensory navigation.
• 😀 The lobster’s compound eyes are mounted on stalks and protected by the rostrum, providing a wide field of vision.
• 😀 The cephalothorax is the combined head and thorax region, marked by a cervical groove that divides the two sections.
• 😀 The lobster’s abdomen includes the telson, a tail-like structure used for movement, and the uropods, which help in swimming.
• 😀 Lobsters swim backward by fanning their uropods and quickly flicking their abdomen to propel themselves.
• 😀 The lobster's mouth has three main types of appendages: maxilla (small, paddle-shaped), mandibles (external jaws for crushing), and maxillipeds (larger structures for grasping food).
• 😀 Lobsters have 10 pairs of walking legs, with the first five pairs having pincers for both walking and food handling.
• 😀 The lobster has sensory bristles on various body parts, such as its mouth parts and walking legs, allowing it to sense its environment.
• 😀 The lobster’s joints are protected by an articular membrane, which is flexible and supports movement, complementing its exoskeleton.

Q & A

What are the large claws of the lobster called, and what is their function?

The large claws of the lobster are called 'Kila pens.' These claws are used for defense and for grabbing food. The structure of the claws includes teeth, which help in crushing and shredding food, highlighting the lobster's dual use of these appendages for both protection and feeding.

What is the rostrum, and what purpose does it serve?

The rostrum is a sharp, pointy structure located in the middle of the lobster's eyes. It serves as protection for the eyes and is also part of the lobster's defense mechanism.

What are the differences between the lobster's antennae and antennules?

The lobster has two types of sensory appendages: antennae and antennules. Antennae are longer and primarily sensory, helping the lobster sense its surroundings, while the smaller antennules are used for more delicate sensing tasks, such as detecting nearby objects or water currents.

What is the cephalothorax, and how does it differ from the abdomen?

The cephalothorax is the combined head and thorax region of the lobster, while the abdomen is the tail section. The cephalothorax houses important sensory organs and appendages, whereas the abdomen is primarily responsible for locomotion and includes structures like the telson and uropods.

What is the function of the lobster's telson and uropods?

The telson is the central extension of the lobster's abdomen, and the uropods are appendages on either side of it. Together, they play a key role in the lobster's ability to swim backwards quickly, especially when escaping predators. The uropods help with balance, and the telson assists with propulsion.

How does the lobster swim backwards, and which appendages are involved?

Lobsters swim backwards by fanning out their uropods to increase surface area and then quickly flexing their abdomen. This motion propels the lobster in reverse, allowing it to escape threats or move through its environment.

What are the three types of mouthparts in a lobster, and what do they do?

The three types of mouthparts in a lobster are the maxilla, mandibles, and maxillipeds. The maxilla are smaller, paddle-shaped structures that help create water currents to bring in plankton. The mandibles are the external jaws used for crushing food. The maxillipeds are larger and help hold and manipulate food for processing.

What are the walking legs of a lobster called, and how do they function?

Lobsters have ten pairs of walking legs, which are used for movement and handling food. The first three pairs are equipped with pincers (chelae) and are used for both walking and grabbing food. The last two pairs are purely for walking and do not have pincers.

What are 'sensory bristles' on a lobster, and where are they located?

Sensory bristles are small, hair-like structures found all over the lobster's body, including on its mouthparts, walking legs, and tail. These bristles help the lobster detect its environment, including the presence of nearby objects or chemicals.

What is the purpose of the articular membrane in lobsters?

The articular membrane is a flexible structure found between the joints of the lobster's appendages. It is not as strong as the exoskeleton but serves to provide flexibility and protect the joints, allowing the lobster to move more efficiently.