Porifera, choanocyte, amoebocyte

Phylum Porifera = sponges

• no tissues
• no organs
• specialized cells to capture food

Cnidaria, cnidocyte, medusa, polyp

flatworms

head region, gastrovascular cavity, bilateral symmetry, move using cilia

bilateral symmetry: An arrangement of body parts such that an organism can be divided equally by a single cut passing longitudinally through it. A bilaterally symmetrical organism has a mirror-image right and left sides.

Radial symmetry: An arrangement of the body parts of an organism like pieces of a pie around an imaginary central axis. Any slice passing longitunally through a radially symmetrical organism's central axis divides it into mirror-image halves.

phylum nematoda: round worms

• waxy cotile
• move using hydrostatic pressure
• alimentary cancal (mouth-------anus)
• most are soil detrivores "eating dead stuff"

• segemented worms
• earthworms
• each segment has a bristle = satae
• organs repeated in segments
• alimentary canal

• insects, crabs, shrimp, spiders
• jointed limbs (crushing, flying, walking, pinching)
• exoskeleton
• alimentary canal
• MOST SUCCESSFUL GROUP!!!

Trophic dynamics refers to process of energy and nutrient transfer between organisms. Trophic dynamics is an important part of the structure and function of ecosystems. Energy is transferred for an ecosystem: Energy gained by primary producers (plants) is consumed by herbivores (H), which are consumed by carnivores, which are themselves consumed by “top-carnivores”.

As one moves up to higher trophic levels (i.e. from plants to top-carnivores) the total amount of energy decreases. Plants exert a “bottom-up” control on the energy structure of ecosystems by determining the total amount of energy that enters the system.

predators can also influence the structure of lower trophic levels from the top-down. These influences can dramatically shift dominant species in terrestrial and marine system^. The interplay and relative strength of top-down vs. bottom-up controls on ecosystem structure and function is an important area of research in the greater field of ecology.

Trophic dynamics can strongly influence rates of decomposition and nutrient cycling in time and in space. For example, herbivory can increase litter decomposition and nutrient cycling via direct changes in litter quality and altered dominant vegetation. Insect herbivory has been shown to increase rates of decomposition and nutrient turnover due to changes in litter quality and increased frass inputs

Herbivores obtain their energy by consuming plants or plant products, carnivores eat herbivores, and detritivores consume the droppings and carcasses of us all.

Describe the difference between radial and bilateral symmetry, gastrovascular cavity and alimentary canal, and invertebrate vs. vertebrate.

Radial symmetry is essentially circular- with one center point, the shape or design of the organism will be symmetrical around that point. Bilateral symmetry is like drawing a line through the center of the organism, and having two matching sides. A butterfly is a great example of this, or a sea star.

A gastrovascular cavity is a digestive sac with only a single opening. An alimentary canal has two openings (a mouth and anus) between its digestive tubes unlike the gastrovascular cavity in which food is ingested and eliminated through the same opening.

Vertebrates have backbones: Mammals, birds, reptiles, fish, amphibians. Invertebrates don't have backbones: Bugs, slugs, shellfish, worms, etc.

Describe the characteristics of the Kingdom Animalia and each phylum & class

Phylum porifera: sponges - no tissues, no organs, and specialized cells.

Phylym cnidaria: usually jellyfish+sea anemones+corals. Radial symmetry this phylum has two distinct body forms: a solitary or colonial polyp and a bell-shaped, free swimming medusa; both polyps and medusae are often fringed with stinging tentacles; the tentacles bear rows of "stinging cells" or cnidoblasts, each containing a "stinging organelle" known as a nematocyst; some coelenterates.

Phylum Platyhelminthes: Body flattened, leaf or ribbonlike, bilaterally symmetrical; digestive tract branched and without an anus, or absent in parasitic forms; this phylum is divided into three classes: Class Turbellaria (free-living flatworms); Class Trematoda (flukes); and Class Cestoda (tapeworms).

Nematoda: round worms. Waxy cotile, move using hydrostatic pressure, alimentary canal, most are soil detritivores "eating dead stuff."

Mollusca: Snails. Body soft with bilateral symmetry, often covered by a mantle that secretes a calcareous shell; usually with an anterior head and a ventral muscular foot for locomotion.

Annelida: segmented worms, earth worms. Each segment has a bristle (setae), organs repeated in segments, alimentary canal.

Arthropoda: insects, crabs, shrimps, spiders. Jointed lims (crushing, flying, walking, pinching). Exoskeleton, alimentary canal. MOST SUCCESSFUL GROUP!!