zoology: animal body plans Flashcards
What kingdom do all animals belong to?
Kingdom Animalia.
What is a body plan in animals?
It is the structural characteristics of an organism that separates it from other organisms, including symmetry, tissue layers, gut openings, and body cavity.
What are true tissues?
True tissues are groups of similar cells that perform specialized functions, like nerve or muscle tissue.
Do sponges (Porifera) have true tissues?
No, they have specialized cells but lack true tissues.
What are the two types of symmetry found in animals?
Radial symmetry (around a central axis) and bilateral symmetry (divisible into mirrored halves).
Which animals are asymmetrical?
Sponges (Porifera).
What is a blind-ending gut?
A digestive system with one opening for both food intake and waste exit.
What is a through-gut?
A digestive system with two openings—one for food intake (mouth) and one for waste exit (anus).
Which animals have a blind-ending gut?
Cnidaria and Platyhelminthes.
Which animals have a through-gut?
Annelida, Arthropoda, and Chordata.
What is cephalisation?
The concentration of nerve cells and sense organs in a head region, aiding in movement and coordination.
What is the coelom?
A body cavity between the mesoderm layers, which can be either fully or partially lined.
What advantages does a coelom provide?
It allows for more complex organ development, movement, and nutrient transport.
What types of skeletons exist in coelomate animals?
Hydrostatic, exoskeleton, and endoskeleton.
What is an exoskeleton?
A solid outer skeleton found in animals like Arthropods.
