What is the difference between gastropods and bivalves?
Bivalve shells are made of two pieces connected at a hinge. So, if you find a shell with a hinge, it must be a bivalve. Gastropods are one piece and usually have a spiral on the end.
Do molluscs have Hemocytes?
There are immune cells in molluscs equivalent to the white blood cells in higher animals that play a role in the non-specific immune response. These cells are called hemocytes. Most of these cells are capable of engulfing extracellular particles by phagocytosis, endocytosis, and encapsulation.
What characteristics differentiate the bivalves gastropods and cephalopods?
Types of Mollusks
- Gastropods include snails and slugs. They use their feet to crawl.
- Bivalves include clams, oysters, and mussels. As their name implies, they have two parts of their shell, which can open and close.
- Cephalopods include the octopus. They have a prominent head and a well-developed brain.
What is the difference between gastropods and mollusks?
Though molluscs are described as bilateral symmetrical, gastropods are asymmetrical. Unlike cephalopods, gastropods have an open circulatory system. Some gastropods are herbivores, while some are carnivores. Terrestrial gastropods have lungs for respiration, while aquatic species have gills.
How are bivalves different from other mollusks?
In all molluscs, the mantle forms a thin membrane that covers the animal’s body and extends out from it in flaps or lobes. In bivalves, the mantle lobes secrete the valves, and the mantle crest secretes the whole hinge mechanism consisting of ligament, byssus threads (where present), and teeth.
What are the characteristics of the three groups of mollusks?
Some of these characteristics are the presence of a shell, the type of shell, the type of foot, the arrangement of teeth in the radula, and the complexity of the nervous system. The three major groups of mollusks are gastropods, bivalves, and cephalopods (SEF ul o pods).
Do humans have Hemocytes?
In addition to the circulating hemocytes, a population of undifferentiated hemocytes resides in the lymph glands that, normally, is only released to the hemolymph during metamorphosis (Holz et al., 2003).
Do molluscs have hemolymph?
Hemolymph (or haemolymph) is the body fluid analogous to blood found in such organisms as mollusks, arthropods, and insects [41,42,43,44,45,46,47,48,49,50]. This complex mixture contains diverse biochemically and pharmacologically active components [25, 51, 52].
How are gastropods different from cephalopods?
Cephalopods are strictly marine creatures — they can only be found in the ocean. Gastropods, on the other hand, can live in a range of different environments. The majority of gastropods are terrestrial, meaning they live on land, but can also be found in the ocean and in freshwater lakes or streams.
What features distinguish the class Bivalvia from the class Gastropoda?
Class Bivalvia consists of mollusks with two shells held together by a muscle; these include oysters, clams, and mussels. Members of class Gastropoda have an asymmetrical body plan and usually have a shell, which can be planospiral or conispiral.
What do gastropods and bivalves have in common?
As the name implies, bivalves have two half-shells called valves that are connected by a dorsal hinge region. Similar to the gastropods, there are a few species of bivalves that have completely lost their shells through evolution.
Where are hemocytes found?
A hemocyte is a cell that plays a role in the immune system of invertebrates. It is found within the hemolymph. Hemocytes are phagocytes of invertebrates.
What do hemocytes do?
Hemocytes are immune effector cells that participate in cellular defenses such as phagocytosis, encapsulation, and clotting. In addition, they mediate systemic immune responses (Lavine and Strand, 2002; Strand, 2008) and are actively involved in synthesizing antimicrobial peptides following an immune challenge.
Do snails have hemolymph?
Hemolymph collected from the snail comprises two fractions: the humoral fraction (plasma) and the cellular fraction containing the immune cells (hemocytes). Laccase activity was determined and characterized in the complete hemolymph, as well as in plasma and hemocytes.
Why is molluscan blood called haemocyanin?
Most molluscs have blue blood because their respiratory molecule is hemocyanin, a type-3 copper-binding protein that turns blue upon oxygen binding. Molluscan hemocyanins are huge cylindrical multimeric glycoproteins that are found freely dissolved in the hemolymph.
What do bivalves lack that gastropods and cephalopods have?
Two of the most prominent features of the bivalve body plan are the lack of a head region and the half shells connected by a dorsal hinge that surround the body. The foot is often smaller in bivalves than in gastropods, and it is usually located more to the front, or anterior, end of the body.