Animal Phyla (Biology Lectures 25 - 28)

Front 1

Porifera

Back 1

- sponges
- "pore bearing"
- no symmetry
- no tissues/organs
- no nervous system
- filter feed
- attach to seafloor or other surface
- secretion for defense mechanism
- hermaphrodites
-reproduces both asexually and sexually

Hint 1

Sponges

Front 2

Cnidaria

Back 2

- radial symmetry
- two tissue layers (endoderm and ectoderm)
- two shapes: medusa and polyp
- medusa: bell shapped with mouth on lower surface
- polyps: tube shaped; one end attaches to a surface
- sting as defense mechanism and way to catch prey
- nervous system: nerve net
- hydrostatic skeleton

Hint 2

Front 3

Platyhelminthes

Back 3

- invertebrates
- bilateral symmetry
- lack coelom
- have a brain
- open circulatory system
- hermaphrodites
- segmented on inside by repeating organs

Hint 3

Front 4

Units of Classification (in correct order)

Back 4

1. Kingdom
2. Phylum
3. Class
4. Order
5. Family
6. Genus
7. Species

Front 5

Annelids/Annelida

Back 5

- bilateral
- have a coelom
- segmented inside and out
- eats soil and filters out the nutrients
- ceolom regulated by nephridia
- closed circulatory system with 5 single-chambered hearts
- brain controls nervous system
- hydrostatic skeleton
- skin is the respiratory surface

Hint 5

Front 6

Mollusca

Back 6

- gills if in water, but lungs instead of gills if on land
- bilateral symmetry
- mantle
- complete digestive system
- types: chitons, gastropods, bivalves, and cephalopods
- chitons probably evolved first
- gastropods live on land
- bivalves have a two part shell
- most have open circulatory system, but cephalopods have closed

Hint 6

Front 7

Nematoda

Back 7

Many species (c. 25,000 described)
--> Roundworms
• Aquatic, terrestrial
•Important parasites (all plants & animals
Interesting Phylum
: Nematoda
have at least one species of nematode)
• Most abundant animals in Antarctica
• Moult (like arthropods)
• Eutelic (fixed number of cells/ species)

Front 8

Arthropoda/Arthropods

Back 8

bilateral symmetry
- segmented body
- exoskeleton
- jointed apendages
- sensory specializations:
-one or more pairs of eyes
-antennae
-specialized developmental stages such as metaphorphosis
- open circulatory system
- complete digestive system
- respiratory system changes within groups of arthropods
- decentralized nervous system, but have ganglia
- very, very diverse
- types: chelicerates (horseshoe crabs and arachnids), crustaceans (crabs, shrimp, lobsters, pill bugs, barnacles), myriapods (millipedes and centipedes), and insects (beetles, ants, butterflies, flies, etc.)

Hint 8

Front 9

Echinoderms

Back 9

- deuterostomes
- begin life with bilateral symmetry, but develop to have radial symmetry
- have endoskeleton that is right under the skin
- non-centralized nervous system
- varied digestive tracts
- gender differentiated
- closed circulatory system
- no brain

Hint 9

Front 10

Chordates/Chordata

Back 10

- deuterostomes
- most are vertebrates, but some are invertebrates
- chordate embryos have:
- notochord
- a dorsal, hollow nerve chord
- gill slits
- a tail that extends beyond the anus
- bilateral
- have coelom
- cephalization
- segmentation
- complete digestive system
- closed circulatory system

Hint 10

Front 11

Acoelomate

Back 11

Have no body cavity

Front 12

Radial vs Bilateral

Back 12

Radial symmetry: The quality of having many lines of symmetry that all pass through a central point.

Bilateral symmetry: Arrangement of body parts so that there are distinct left and right halves that mirror each other

Front 13

Cephalization

Back 13

Concentration of sense organs and nerve cells at the front of an animal's body.

Front 14

Protostome

Back 14

Animal whose mouth is formed from its blastopore (everything else).

Front 15

Monecious

Back 15

Hermaphroditic

Front 16

E.g. Chordata

Back 16

Example: mammals, birds, lizards, sharks. Dorsal nerve cord, backbone wraps around nerve cord (notocord), post-anal tail, pharyngeal gill slits.

Front 17

E.g. Mollusca

Back 17

Example: clams, snail, squid. Possess shell, but no skeleton, mantle produces shell, tube feet, radula (tongue with spines)

Front 18

E.g. Cnidaria

Back 18

Example: anemone, coral, jellyfish. Possess tentacles, stinging cells, one cavity (mouth AND anus), jelly in between layers, marine, no skeleton

Front 19

Phylum: Tardigrada

Back 19

‘Water bears’ or ‘Moss Piglets’
• Live in fresh water, moss and undergrowth
• Capable of surviving extremes (10 years without wa
ter)
• On final flight of space shuttle Endeavour (May 20
11)
Phylum: Tardigrada
• Also eutelic (species specific number of cells)

Hint 19

Front 20

Know your Phyla: 5 Criteria

Back 20

1. SYMMETRY - what kind?
2. GERM LAYERS - how many?
3. COELOM (body cavity) - present or absent?
4. BLASTOPORE - does it form mouth or anus?
5. SEGMENTATION - present or absent?

Front 21

Importance of the Coelom

Back 21

--> Fluid-filled so can be used as internal support
•Separates internal processes from gut
The importance of the coelom
Coelom
• Allows transport of fluids (circulatory and excretory
systems)
• Provides space for development of internal organs
• Enables increased body size

Front 22

Mantle

Back 22

Dorsal body wall of mollusc which often forms shell

Front 23

Mantle Cavity

Back 23

In molluscs, the space between mantle and main body
where gills (or lungs in terrestrial snails) are found

Front 24

Notochord

Back 24

A stiff rod of mesoderm found next to the nerve chord in all chordate embryos (and some adults)