Vert Lecture PPT

Vert Lecture PPT - Lecture 10: Vertebrates Chapter 34...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
Lecture 10: Vertebrates Chapter 34
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Shared dervied traits of chordates dorsal hollow nerve cord - develops from rolled ectoderm notochord - longitudinal flexible support rod; in humans develops into “discs” post-anal tail - significant portion of the body posterior to the anus (non-chordates anus is terminal) pharyngeal clefts - grooves in tissue surrounding pharynx that develop into slits (or later, into ear, head, and neck parts)
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Urochordata - deepest branching lineage of chordates tunicate - “sea squirts” larvae exhibits all four chordate characters, but most are lost during morphogenesis
Background image of page 4
Cephalochordata - the lancelets adult lancelet exhibits all four chordate characteristics suspension feeding: swim up, sink down (larvae) vs. dig in and filter (adult) muscles used for swimming (develop from blocks of mesoderm along notochord of chordates, called somites ) evolution: a fast maturing urochordata larva that never undergoes morphogenesis? - no.
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Cephalochordata - possess a primitive brain Hox gene orthologs are expressed in overlapping locations in vertebrate and lancelet Lancelet brain, although very simple, is likely an evolutionary precursor to the
Background image of page 6
Craniates - evolution of a head (brain, sensory organs, and skull) allowed active predation possess two clusters of Hox genes - not one - and additional gene duplications neural crest - give rise to teeth, skull parts, inner layer of skin, neurons pharyngeal clefts develop into more than just filtration system
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Myxini = Hagfishes cartilaginous skull, small brain, eyes teeth-like structures of keratin nasal opening that connects to pharynx adult retain notochord rows of slime glands running the length of body
Background image of page 8
Duplication of Dlx genes: increased complexity of the nervous system and skeleton (skull and backbone) Variations of vertebrae: small prongs of cartilage along the notochord;
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 11/24/2011 for the course BIOLOGY 110 taught by Professor Bentz during the Spring '09 term at Drexel.

Page1 / 40

Vert Lecture PPT - Lecture 10: Vertebrates Chapter 34...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online