ch 9.3- diversity of life Flashcards
chordates example
vertebrates
chordates body symmetry
bilateral
chordates tissue organization
triploblasts
chordates embryonic devleopment
deuterostome
blastopore forms anus
chordates general characteristics
all chordates have segmented bodies
what are some shared traits of all chordates
- Dorsal hollow nerve cord: Forms the central
nervous system (brain and spinal cord). - Notochord: Cartilaginous rod derived from
mesoderm. Forms the primitive axis and supports
the body during embryonic development.
Develops into the spinal bones (not spinal cord). - Pharyngeal gill slits: Forms pharynx, gills, feeding
structures, or head and neck structures. - Post-anal tail: Lost during embryonic
development in humans and many other
chordates.
what are the types of invertebrates
lancelets
tunicates
lancelets
invertebrate chordates
known as amphioxus
subphylum- cephalochordata
lancelets circulator system
closed
lacks heart
contains contractile blood vessels
lancelets respiratory system
diffusion (body wall)
general characteristics lancelets
Filter feeders,
external sexual reproduction, live in benthic
habitats (bottom of a body of water).
tunicates
known as urochordata
sumphylum- tunicata
tunicates circulatory system
both closed and open circulatory systems
tunicata respiratory system
gills
tunicata general characteristics
Sessile, filter
feeders, hermaphroditic, sexual and asexual
(budding) reproduction, live in benthic
habitats, notochord in larvae.
jawless fish
● E.g., agnatha, lamprey, hagfish.
● Subphylum: Vertebrata.
● Circulatory system: Two-chambered heart.
● Respiratory system: Gills, countercurrent
exchange.
● General characteristics: No fins,
cold-blooded. Hagfish have secondarily lost
vertebrae.
cartilaginous fish
● E.g., shark.
● Subphylum: Vertebrata.
● Circulatory system: Two-chambered heart.
● Respiratory system: Gills.
● General characteristics: Jaws and teeth.
Skeletons made of cartilage (chondrichthyes).
bony fish
● E.g., salmon, halibut.
● Subphylum: Vertebrata.
● Circulatory system: Two-chambered heart.
● Respiratory system: Gills.
● General characteristics: Bony skeleton
(osteichthyes). Includes ray-finned fish
(actinopterygii) and lobe-finned fish
(sarcopterygii).
amphibia
● E.g., frog, toad, salamander, newt.
● Subphylum: Vertebrata.
● Circulatory system: Three-chambered heart.
● Respiratory system: Gills (juvenile), Lungs
(adult).
● General characteristics: No scales. Undergo
metamorphosis. Tadpoles (aquatic) have tails,
no legs. Adults (terrestrial) two pairs of legs.
Frogs and toads lose tails.
mammalia monotremes
● E.g., duckbill platypus, spiny anteater.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered heart.
● Respiratory system: Lungs.
● General characteristics: Only mammals that
lay eggs.
mammalia masupials
● E.g., kangaroo, opossum.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered heart.
● Respiratory system: Lungs.
● General characteristics: Carry their young in
a pouch.
mammalia placental
● E.g., bat, whale, mouse, human.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered heart.
● Respiratory system: Lungs.
● General characteristics: Placenta supports
fetus.
reptilia
● E.g., turtle, snake, crocodile, alligator.
● Subphylum: Vertebrata.
● Circulatory system: Three-chambered heart
(exception: crocodiles and alligators have a
four-chambered heart).
● Respiratory system: Lungs.
● General characteristics: Internal fertilization,
cold blooded.
birds
● E.g., eagle, blue jay.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered heart.
● Respiratory system: Lungs.
● General characteristics: Eggs in shell
evolution of chordates
Notochord (lancelets + tunicates)
↓
Head (hagfish)
↓
Vertebral column (jawless fish, lampreys)
↓
Jaws and mineralized skeleton (sharks)
↓
Lungs (ray-finned fish)
↓
Lobed fins
↓
Limbs with digits (amphibians)
↓
Amniotic eggs (reptiles)
↓
Milk production (mammals)
