ch 9.3- diversity of life

Question 1

chordates example

Answer 1

vertebrates

Question 2

chordates body symmetry

Answer 2

bilateral

Question 3

chordates tissue organization

Answer 3

triploblasts

Question 4

chordates embryonic devleopment

Answer 4

deuterostome

blastopore forms anus

Question 5

chordates general characteristics

Answer 5

all chordates have segmented bodies

Question 6

what are some shared traits of all chordates

Answer 6

1. Dorsal hollow nerve cord: Forms the central
   nervous system (brain and spinal cord).
2. 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).
3. Pharyngeal gill slits: Forms pharynx, gills, feeding
   structures, or head and neck structures.
4. Post-anal tail: Lost during embryonic
   development in humans and many other
   chordates.

Question 7

what are the types of invertebrates

Answer 7

lancelets

tunicates

Question 8

lancelets

Answer 8

invertebrate chordates

known as amphioxus
subphylum- cephalochordata

Question 9

lancelets circulator system

Answer 9

closed
lacks heart
contains contractile blood vessels

Question 10

lancelets respiratory system

Answer 10

diffusion (body wall)

Question 11

general characteristics lancelets

Answer 11

Filter feeders,
external sexual reproduction, live in benthic
habitats (bottom of a body of water).

Question 12

tunicates

Answer 12

known as urochordata

sumphylum- tunicata

Question 13

tunicates circulatory system

Answer 13

both closed and open circulatory systems

Question 14

tunicata respiratory system

Answer 14

gills

Question 15

tunicata general characteristics

Answer 15

Sessile, filter
feeders, hermaphroditic, sexual and asexual
(budding) reproduction, live in benthic
habitats, notochord in larvae.

Question 16

jawless fish

Answer 16

● 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.

Question 17

cartilaginous fish

Answer 17

● E.g., shark.
● Subphylum: Vertebrata.
● Circulatory system: Two-chambered heart.
● Respiratory system: Gills.
● General characteristics: Jaws and teeth.
Skeletons made of cartilage (chondrichthyes).

Question 18

bony fish

Answer 18

● 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).

Question 19

amphibia

Answer 19

● 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.

Question 20

mammalia monotremes

Answer 20

● E.g., duckbill platypus, spiny anteater.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered heart.
● Respiratory system: Lungs.
● General characteristics: Only mammals that
lay eggs.

Question 21

mammalia masupials

Answer 21

● E.g., kangaroo, opossum.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered heart.
● Respiratory system: Lungs.
● General characteristics: Carry their young in
a pouch.

Question 22

mammalia placental

Answer 22

● E.g., bat, whale, mouse, human.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered heart.
● Respiratory system: Lungs.
● General characteristics: Placenta supports
fetus.

Question 23

reptilia

Answer 23

● 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.

Question 24

birds

Answer 24

● E.g., eagle, blue jay.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered heart.
● Respiratory system: Lungs.
● General characteristics: Eggs in shell

Question 25

evolution of chordates

Answer 25

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)