What type of symmetry do crustaceans have?
What type of symmetry do crustaceans have?
Symmetry: Bilateral; segmented body regions organized into head, thorax and abdomen.
Do crayfish have bilateral nervous system?
The crayfish has a ventral nerve cord that goes from the tail to the head. The nerve cord will lead to a small bundle, which is considered the brain. Crayfish primarily sense with their antennae, compound eyes on stalks, whereas earthworms sense without eyes and use sensors.
How are crustaceans classified?
Crustaceans (Crustacea /krʌˈsteɪʃə/) form a large, diverse arthropod taxon which includes such animals as crabs, lobsters, crayfish, shrimps, prawns, krill, woodlice, and barnacles. Like other arthropods, crustaceans have an exoskeleton, which they moult to grow.
Why are crustaceans categorized together?
These animals are closely related because of two main characteristics that they share: they all have an exoskeleton (outer skeleton) and they all have joint appendages. Lobsters are farther categorized into the class Crustacea, along with other marine organisms like crabs and shrimp.
What animals eat crustaceans?
Raccoons, opossums, apes, monkeys, rats, seals and sea lions among others enjoy a crustacean feast if it presents itself. Land-dwelling crustaceans such as various hermit crabs run the risk of consumption by any number of larger carnivorous predators.
Are crustaceans and shellfish the same?
Contrary to popular belief, the terms ‘crustaceans’ and ‘shellfish’ are not interchangeable. In fact, the correlation between these two categories only goes one way: while crustaceans are always shellfish, shellfish are not always crustaceans.
Do jellyfish have blood?
Lacking brains, blood, or even hearts, jellyfish are pretty simple critters. They are composed of three layers: an outer layer, called the epidermis; a middle layer made of a thick, elastic, jelly-like substance called mesoglea; and an inner layer, called the gastrodermis.
What is the difference between soul and spirit?
Our soul is reflected in our personality. The Greek word for spirit is pneuma. It refers to the part of man that connects and communicates with God. Our spirit differs from our soul because our spirit is always pointed toward and exists exclusively for God, whereas our soul can be self-centered.
Where is your soul located in your body?
The soul or atman, credited with the ability to enliven the body, was located by ancient anatomists and philosophers in the lungs or heart, in the pineal gland (Descartes), and generally in the brain.