apbio animal diversity

• Animals are:

• Multicellular

• Heterotrophs

• Eukaryotic

• Have tissues and differentiated cells

• Eat

• Reproduce and Develop

Sperm and egg meet through fertilization to form a

zygote

blastula,

multi-celled hollow ball

Protostomes

• worms and bugs, develop a mouth first during fetal development.They include groups like arthropods and mollusks.

Deuterostomes

• people and starfish, develop an anus before they develop mouths.

 radial symmetry,

symmetry inn the up and down plane

bilateral symetry

sideways plane

cephalization

animals with head regions.

Invertebrates

• animals without a backbone.

Porifera

• Porifera are the sponges.

• They have radial symmetry.

• They are non-motile filter feeders.

• Individual cells are specialized, but they have no true organs or tissues.

Cnidaria

• Cnidarians include hydras, jellyfish, sea anemones, and coral.

• They have radial symmetry.

• They have stinging threads.

• They can be polyps (stuck to the ocean floor), or medusa (floating jellyfish).

• Mouths lead to gastrovascular cavities where food is digested.

Platyhelminthes

• flatworms, planarians, and flukes.

• They are the simplest animals with bilateral symmetry.

• Flukes and tapeworms are parasitic flatworms.

Nematoda

• Nematodes are roundworms.

• They are the first animals to evolve a complete digestive tract.

• They are used in research and found in undercooked pork.

Mollusca

• Mollusca are the mollusks. 

• They are the first animals with a true circulatory system and a nervous system.

• They have radulas which are used to scrape up food.

• Mollusks have a foot for locomotion, a mass where the organs are housed, and a mantle which protects them.

Gastropods

sea slugs, snails and slugs

Bivalves

• clams, oysters, mussels, and scallops (2 hinged shells)

Cephalopods

• built for speed and motility, include squid and octopi; have sophisticated sense organs.

Annelida

• Annelids include earthworms, Christmas tree worms, polychaetes (sand worms) and leeches.

• Annelids are the first animals to have segmented bodies and a coelom.

• Coelom (pronouce:selum): is a main body cavity that surrounds and contains the digestive tract/organs.

Arthropoda

• Arthropods include crayfish, lobsters, crabs, barnacles, scorpions, millipedes, centipedes, spiders, ticks, and insects.

• t is the largest phyla by number of animals.

• Arthropods have a hard exoskeleton.

• Crustaceans like lobsters and crayfish are arthropods.

• Insects have 6 legs and a pair of wings; and a body made of a head, thorax, and abdomen.

• Arachnids have 8 legs and include the spiders.

Echinodermata

• Echinoderms are sea stars, sand dollars, and sea urchins.

• They have spiny skin and an endoskeleton.

• They have a water vascular system that is used for movement.

• They are radially symmetrical as adults, and bilateral as larvae. 

Chordata

•  a dorsal, hollow nerve cord

• 2. a notochord (flexible rod between the digestive tract and the nerve cord)

• 3. Pharyngeal slits (gills)

• 4. Muscular post-anal tail 

• Some chordates are actually invertebrates: the tunicates and lancelets.

• Tunicates are stationary and look like small bags.

• Lancelets are small, bladelike animals that live in sand.

Most chordates are

• vertebrates: have a segmented backbone

• Their endoskeletons include a skull

• Their backbone is composed of vertebrae

agnathans

animals wiothout jaws

5 Main Classes of Vertebrates

• Fish

• Amphibians

• Reptiles

• Birds

• Mammals

1st class of fish, Chondrichthyes

cartilaginous fishes such as sharks and rays. They have a lateral line system, a sense organ used to detect vibrations.

Osteichthyes

 bony fishes such as tuna and trout

• a buoyant swim bladder

• more mobile fins

• Class Amphibia is represented today by

the first land vertebrates

• frogs

• toads

• salamanders

• Their 4 limbs (tetrapods) allow them to move on land

• However, amphibian larvae must develop in water (and go through metamorphosis)

• Found in damp habitats

• Threatened by fungal pathogens, habitat loss, acid rain, and pollution

class reptilia

• able to live on land due to

  • waterproof scales

  • a shelled, amniotic egg

• Modern reptiles are ectotherms (cold blooded)

  • They warm their bodies by absorbing heat from the environment

• Include turtles, alligators, crocodiles, lizards, and snakes

endothermic,

produces own body heat

class birds

• scales

• amniotic eggs

• No bladders

• Only one ovary

• Light bones

• Wings and feathers

• an endothermic metabolism

• hollow bones

• a highly efficient circulatory system

• A 4 chambered heart

class mamailia

• Class Mammalia descended from reptiles 

• Mammals are endothermic (warm blooded)

• There are two unique mammalian characteristics

  • Hair, which insulates the body

  • Mammary glands, which produce milk that nourishes their young

Monotremes

mammals
lay eggs-

Marsupials

• The tiny offspring complete development inside a pouch

• Example: kangaroos, koalas, wombats, Tasmanian devils

• eutherians, also called placentals

• They have a relatively long gestation

• Complete embryonic development occurs within the mother, in a sac called a placenta

porferia animals

sponges

cnidaria

jellyfish, sea anemones, hydras ,corals

Platyhelminthes animals

• flatworms, planarians, and flukes.

Nematoda animals

nemotoads/roundworms

Mollusca

• sea slugs, snails and slugs

 clams, oysters, mussels, and scallops (2 hinged shells)

squid and octopi;

Annelida animals

• earthworms, Christmas tree worms, polychaetes (sand worms) and leeches.

Arthropoda animals

• crayfish, lobsters, crabs, barnacles, scorpions, millipedes, centipedes, spiders, ticks, and insects.

Echinodermata animals

• sea stars, sand dollars, and sea urchins.