Invertebrate animal Flashcards
Vertebrates
Description Vertebrates comprise all species of animals within the subphylum Vertebrata.
Invertebrates
Invertebrates are animals that neither possess nor develop a vertebral column,
Ganglion
a structure containing a number of nerve cell bodies, typically linked by synapses, and often forming a swelling on a nerve fiber.
Bilateral Symmetry
the property of being divisible into symmetrical halves on either side of a unique plane.
Radial Symmetry
symmetry around a central axis, as in a starfish or a tulip flower.
Asymmetry
lack of equality or equivalence between parts or aspects of something; lack of symmetry.
Open circulatory system
evolved in crustaceans, insects, mollusks and other invertebrates pump blood into a hemocoel with the blood diffusing back to the circulatory system between cells.
Closed circulatory system
a few invertebrates, have a closed circulatory system. Closed circulatory systems have the blood closed at all times within vessels of different size and wall thickness.
Exoskeleton
a rigid external covering for the body in some invertebrate animals, especially arthropods, providing both support and protection.
Antenna
sometimes referred to as “feelers”, are paired appendages used for sensing in arthropods. Antennae are connected to the first one or two segments of the arthropod head.
Endoskeleton
an internal skeleton, such as the bony or cartilaginous skeleton of vertebrates.
Water vascular system
(in an echinoderm) a network of water vessels in the body, the tube feet being operated by hydraulic pressure within the vessels.
