TERMS
KINGDOM ANIMALIA
Symmetry

Asymmetrical – no body symmetry


Radial – similar parts branch out in all directions from a central
line



Ex: Sponges – have no true tissues
Have a top and bottom side, but no front or back
Ex: Cnidarians
Bilateral – two similar halves on either side of the body


Have dorsal, ventral, anterior and posterior portions to the animal
Exhibit cephalization – concentration of sensory and brain structures in
the anterior end of the animal
Body Cavity

Based on Embryological Tissues
 Ectoderm,

Mesoderm, Endoderm
Acoelomate – body cavity absent
Body Cavity

Pseudocoelomate – digestive tract is not lined with
mesoderm
 Cavity
between endoderm and mesoderm
Body Cavity

Coelomate
 Cavity
fully lined by mesoderm
 Mesoderm lines and supports the gut
Nutrition and Digestion

Nutrition – mainly by ingestion

One or Two Openings
Gastrovascular cavity – single opening for digestion and
ingestion; found in cnidarians, ctenophores and flatworms
 Alimentary canal – two openings for digestive tract


Digestive Structures
Circulation

Diffusion / Osmosis





Diffusion – allows carbon dioxide to diffuse out of the blood and oxygen to
diffuse into the blood
Osmosis -
Open System - A system in which the circulating fluid is not enclosed in
vessels at all times; found in insects, crayfish, some mollusks, and other
invertebrates.
Closed System - A system that uses a continuous series of vessels of
different sizes to deliver blood to body cells and return it to the heart;
found in echinoderms and vertebrates.
Heart Structure

Number of Chambers in Vertebrate


Three chambered heart – amphibians, reptiles
Four chambered heart – birds, mammals
Respiration

Diffusion

Structures



Gills – an organ specialized for the exchange of gasses with water
Book Lungs – in the abdomen of an arachnid, an organ for gas
exchange with parallel folds that resembles the pages of a book
Tracheal Tubes


In insects, myriapods: one of a network or air tubes that brings air directly to
the tissues
Lungs – the respiratory organ where gas exchange occurs

In vertebrates: tubes connect the pharynx to the lung
Reproduction

External / Internal Fertilization



Eggs – types


Amniotic Egg – embryo encased in a self-contained aquatic environment’
Amniotes – animals that produce an amnion


External – the union of gametes outside the bodies of the parents, as in many fishes
and amphibians
Internal – fertilization in which sperm fuses with an egg inside the female’s body, as in
reptiles, mammals and cartilaginous fishes
Reptiles, birds, mammals
Types of birth

Oviparous – eggs that that hatch outside of the mothers body



Most reptiles, all birds, three species of mammals
Ovoviparous - eggs stored inside the mothers body and are laid right before
hatching or born alive
Viviparous – no shell forms around the egg, and the young are kept inside of the
mother’s body until they are mature enough to be born

Most mammals, a few species of lizards and snakes
Water Regulation & Excretion

Water Balance



Removal of excess water
Conservation of water
Excretory Terms & Structures


Flame Cells – in flatworms, a cell that collects excess body water and
transfers it to the excretory system
Malphigian Tubules – main excretory organs of insects; they collect body
fluids and wastes and carry them to the intestine


Nephridia / Metanephridia – excretory tubules that eliminate cellular waste
and excess water in earthworms


Water is reabsorbed by the body, and wastes leave the body in a nearly solid
form
Some water is reabsorbed by blood vessels
Kidneys – found in vertebrates; they filter wastes from the blood while
regulating water levels in the body
Support

Hydrostatic Skeleton – a fluid-filled cavity surrounded by
muscles. The pressure of the fluid, and the action of the
surrounding muscles are used to create movement


Exoskeleton – the hard, external covering of some
invertebrates that provides protection and support


Echinoderms, cnidarians, annelids, nematodes
Arthropods (insects, spiders, crustaceans) and shelled mollucs
Endoskeleton – an internal skeleton

Chordata, Echinodermata, Poriferia
Nervous System




Nerves – a strand of axons through which impulses
travel
Nerve net – a diffuse web of interconnected nerve
cells in the nervous system of cnidarians
Ganglion – a mass of nerve cells
Cephalization – concentration of nervous tissue and
sensory organs at the anterior end of an organism