Characteristics of animals
-heterotrophic and usually ingest food followed by digestion in a central cavity
-locomotion by mean of muscles
-multicellular eukarotes, high degree of cel specialization
-adult is usually diploid and produces gametes by meiosis.
-reproduction usually sexual with embryo undergoing developmental stages.
No particular symmetry
Circular organization can be bisected in many planes to produce mirror images, some sessile.
Define right and left halves. only a cut down the midline will produce mirror images.
no true tissues
have ectoderm and endoderm germ tissue layers
have ectroderm, endoderm, and mesoderm gym tissue layers
The fate of the blastopore in deutrosomes
embryos the first opening (blastopore) becomes the anus
the fate of the blastopore in protosome
embryos the first opening (blastopore) becomes the mouth
Phyla are deuterosomes
echinoderms and chrodates
Phyla are Protostomes
flat worms, molluscs, amelids, roundworms, and arthropods.
Characteristics of Sponges
- body with many pores
- sessile filter feeders
- asexual and sexual reproduction
- have the cellular level of organization
How a sponge feeds
-flagella of collar cells beat to move water through sponge.
-current of water moves in through pores and out through osculum
- food is filtered and engulfed by collar cells, then amoeboid cells digest it and transport its nutrient.
Symmetry of sponges
symmetry of cnidarians
symmetry of flatworms
Characterisics of flatworms and parasitic flatworms
- no coelem
- three germ layers and organ level of organism
- can be free living or parasitic
- lack respiratory and circulatory systems but flt body allows for sufficient gas exchange
- parasitic flatworms mainly have a very well developed reproductive system
- income digestive tract - one one opening, mouth also functions as the anus.
body cavity is completely lined with mesoderm germ tissue
a true coelom
advantages of have a true coelem
-free body movement
-space for development of complex organs
- greater surface area for absorption of nutrients
- protection of internal organs
Roles of visceral mass, foot, and mantle in molluscs
visceral mass- includes most organs (ex. kidneys, stomach).
foot- muscular portion usually used for locomotion
mantle- secretes a shell
Distinguish between class of molluscs
-foot is ventral (near stomach) flattened, and used by locomotion.
gave a spiral shell
foot have evolved into funnel or siphon near the head.
-two part hinged shell
-the hatchet shaped foot is used to burrown
Characteristics of Annelids
- true coelem
-complete digestive tract
-nervous system consist of brain, ventral nerve cord, and ganglia in each segment
Characteristcs of rounds worms
- complete digestive tract
- pseudocoelem- body cavit that is not completely lined with mesoderm
Most diverse phylum
- protects them
- prevents them from drying out
- provide a place for muscle attachment to move the body.
- must molt to grow
have a harder, more calcifid shell
Three body regions: head, throax, and abdomens
three pairs of legs
have chelicerai (fang-like) mouthparts