Origin And Evolution Of Vertebrates

Question 1

Vertebrates

Answer 1

Animals w/ backbones; part of the chordata

Question 2

What are the four key characteristics of chordates?

Answer 2

Notochord, dorsal and hollow nerve cord, post anal tail, pharyngeal slits or clefts

Question 3

Pharyngeal slits or clefts

Answer 3

Do respiration

Question 4

Notochord

Answer 4

Gives shape (w/o it becomes floppy); gives skeletal structure for muscles to push against for movement

Question 5

Dorsal, nerve cord

Answer 5

Acts as a spinal cord

Question 6

Post anal tail

Answer 6

Allows for movement (swimming)

Question 7

Cephlochordata

Answer 7

“Head-cord”; Ex: lancelets

Question 8

Urochordata

Answer 8

Sucks water in, similar to sponges; gills form a basket; juveniles have a notified and post anal tail while adults don’t; adults gained ability to filter feed

Question 9

Homeobox genes

Answer 9

Control arrangement and number of body parts; changes in HOX genes can radically alter a body plan

Question 10

Vetebrata

Answer 10

Spinal cord enclosed by vertebrae; neural crest, genome duplication

Question 11

How is the neural crest formed and what is it?

Answer 11

Ectoderm closes to form neural tube. The neural crest cells leave and form certain parts of the jaw. Forms a bony jaw.

Question 12

What does genome duplication in vertebrates allow for?

Answer 12

Space for mutation

Question 13

Cyclostomata

Answer 13

Part of the vertebrates; “circle mouths”; have no limbs and swim back and forth; include Myxini and Petromyzontida

Question 14

Myxini

Answer 14

Cyclostomata; hagfishes-fish w/ no jaws; produces slime for defense

Question 15

Petromyzontida

Answer 15

Part of Cyclostomata; lampreys; sucker fish w/ bony teeth; parasitic-need a host

Question 16

Gnathostomata

Answer 16

Part of vertebrates; have jaws; jaws evolved from gill arches (allows water to move gills)

Question 17

Chondrichthyes

Answer 17

Part of the gnathostomata;have cartilaginous skeletons and bony jaws; have paired fins which allow them to steer and move fast; Ex: sharks, skates, rays, chimaeras, and ratfishes

Question 18

Osteichthyes

Answer 18

Bony fishes; entire skeleton is bony

Question 19

Actinopterygii (ray finned fishes)

Answer 19

Part of the osteichthyes; incredibly diverse (over 30-40 species); bony head and skeleton, ray fins that allow to control shape of fin

Question 20

Lobe finned fishes

Answer 20

Part of the osteichthyes; Ex: Actinistia (Coelaccanths) and Dipnoi (Lungfishes)

Question 21

Actinistia (Coelaccanths)

Answer 21

Are lobe finned fish; tails and fins are muscular; find supported by long bones

Question 22

Dipnoi (Lungfishes)

Answer 22

Are lobe finned fishes; need air to survive; have well-developed lungs

Question 23

Tiktaalik

Answer 23

Transitional fossil from lobe finned fishes to tetrapods; fish arm w/ ray fins to tetrapods arm w/ multiple bones

Question 24

Tetrapods

Answer 24

Have “fingers”; evolved from lobe finned fishes

Question 25

Amphibia

Answer 25

First tetrapods; “dual-life”; have to lay eggs in water; babies go through metamorphosis; adults require moisture

Question 26

Which trait is not a shared, derived character defining the vertebrata?

Neural crest
Vertebrae
Notocord
Whole genome duplication

Answer 26

Notocord