Invertebrates Flashcards
Master Invertebrates (14 cards)
What are Invertebrates
Animals that neither process nor develop a vertebral column, derived from notochord
What are the General characteristics of Invertebrates
-Don’t have lungs
-Many have shells or exoskeleton
-Heterotrophic
Types of Invertebrates
-Terrestrial Invertebrates
-Freshwater and marine Invertebrates
What are phylum of invertebrates
1.Potifera (Sponges)
2.Cnidera (Coelenterates)
3.Plantyhelminthes(Flatworms
4.Nematoda(roundworms)
5.Annelida(segmented worms)
6. Mollusca(Mollusks)
7. Arthropoda(Arthropods)
8.(Echinodermata(Echinoderms)
9.Ctenophora(Comb jellies)
10. Rotifera (Rotifers)
What are key Characteristics of Porifera
Also called sponges
-have porous body
-are asymmetrical/ radially symmetrical
-consists of three layers: Pinacoderm, Mesohyl, Choanoderm
-Water enters via small pores(ostia) and exits through large openings(osculum)
-they are filter feeders, collar cells that help in trapping and ingesting food particles
-produce both sexually and a sexually
_bodies supported by spicules(made of silica)
What are the key characteristics of a Cnidaria(Coelenterates)?
-are radial symmetry
-have a blind sac
-Diploblastic(outer layer> epidermis, inner layer>gastrodermis, middle jelly like >mesoglea
- don’t have true circulatory system/ respiratory system
-Have cnidocytes( special cells that inject toxins into prey or for defense)
-have incomplete digestive system called gastrovascular cavity
-produce sexually and asexually
-have a simple nerve net instead of centralized brain
What are the Characteristics of Platyhelminthes(Flatworms)
-are dorsoventrally flattened, bilateral symmetry
-are triploblastic(three germ layers>ectoderm, mesoderm, endoderm
-lack body cavity
-have incomplete digestive system
-have flame cells which help in excretion and metabolic wastes
-reproduce both sexually and asexually
-hermaphroditic(both males and females)
What are the key characteristics of Nematoda(roundworms)
- have a cylindrical, elongated and unsegmented body
-bilateral symmetry
-are pseudocoelomates( have body cavity that is not completely lined with mesoderm-derived tissues
-have cuticle( tough, flexible and non-living layer
-have complete digestive system
-have a simple nervous system with a ring of nervous tissue
-have longitudinal muscles
-have not respiratory and circulatory systems, gas exchanges through diffusion across the body
what are the key characteristics of Annelida(Segmented worms)
-Body is divided into segments called metameres
-are coelomates(have true body cavity/coelom fully lined by mesoderm
-have a complete digestive system
-have closed circulatory system circulatory system(blood is contained within vessels)
- They respire via skin
-have a well developed nervous system
produce either sexually or asexually
-hermaphroditic
What are the key Characteristics of Mollusca(Mollusks)
-have a soft, unsegmented body containing; Head-foot, visceral Mass, Mantle
-Have shells made of Calcium Carbonate, made of three parts; Periostracum, prismatic, nacreous
-Have coelomates(true body cavity
-have n open circulatory system, where the hemolymph flows freely through cavities
-some like cephalopods have closed circulatory system
-Have a simple nervous system with a nerve cords and ganglia different from cephalopods which have a complex one
- reproduce sexually and some are hermaphroditic
Classification of Mollusca
1.Gastropoda (Snails and Slugs):
-Largest class of mollusks
-Characterized by a spiral-shaped shell or no shell at all
-Exhibits torsion (body twisting during development)
-Examples: Helix (garden snail), Aplysia (sea hare), slugs
2.Bivalvia (Clams, Oysters, Mussels):
Two hinged shells (valves)
-Lack radula, feed by filtering plankton
-Mostly sessile or semi-sessile
-Examples: Mytilus (mussel), Ostrea (oyster), Pecten (scallop)
3.Cephalopoda (Squids, Octopuses, Cuttlefish):
-Highly developed nervous system, complex behavior
-Reduced/internal or no shell
-Active predators with advanced sensory organs
Examples: Octopus vulgaris (common octopus), Loligo (squid), Nautilus
What are the key characteristics of Arthropoda(Arthropods)
-They are exoskeleton(have an skeleton outside the body) made of chitin to support, protection and prevents water loss
the body is segmented into distinct regions; Head, Thorax, Abdomen
–Have jointed appendages that allow flexibility and a wide range of movement
-Have Coelomates
-Have a well developed nervous system with cerebral ganglia(brain)
-Have different types of respiratory systems: -insects> breathe via system of tracheae, Aquatic arthropods> breathe via gills, Arachnids> book lungs
- have open circulatory system
-reproduce sexually
What are the classification of Arthropoda?
- Hexapoda(Insects)
-have three pair of legs
-three body segments(head, thorax, abdomen) - Crustacea(Crustaceans):
- have two pairs of antennae, gills for respiration and a shell - Arachnida(Arachnids):
-comprised of eight legged arthropods
-have two main body segments
4.Myriapoda(Myriapods)
-have numerous body segments and many legs
5.Chelicerata
- have Chelicerae, they chew ,crush or tear food horizontally
5.Mandibulata
-have Mandibles, they chew ,crush or tear food vertically
What are the key characteristics of Echinodermata?
Body Symmetry:
Radial symmetry in adults, typically five-part (pentamerous)
Bilateral symmetry in larval stages
Endoskeleton:
Internal skeleton made of calcium carbonate plates (ossicles)
Ossicles may be fused or flexible; skin may have spines or tubercles
Water Vascular System:
Fluid-filled canals used for locomotion, feeding, respiration
Includes tube feet for movement and manipulation of objects
Movement:
Powered by tube feet, driven by the water vascular system
Respiration:
Gas exchange through papulae (skin gills) or tube feet
Digestive System:
Complete digestive system, with some species able to evert stomach for external digestion
Reproduction:
Mostly sexual with external fertilization; some can reproduce asexually via regeneration or fragmentation
