Class Notes (808,131)
Canada (493,086)
Zoology (202)
ZOO 2090 (90)
Lecture 4

Lecture 4.docx

3 Pages
Unlock Document

University of Guelph
ZOO 2090
Fred Laberge

Lecture 4 ZOO*2090 September 18, 2013 Development Objectives - describe basic germ layers & 4 basic tissue types they generate - concepts of differentiations and organogenesis - timing of developmental events and how play role in phylogenetic change Early Development - Cleavage: from zygote to multicellular hollow blastula - Gastrulation and neurulation: formation of germ layers - Differentiation and organogenesis: from germ layers to organs o cleavage: from zygote to multicellular hollow blastula o gastrulation: formation of germ layers o neurulation: formation of neural tube Lecture 4 ZOO*2090 September 18, 2013 - differentiation: form germ layers to basic tissues o 4 primary tissues:  epithelium  connective tissues  muscle  nervous tissue - organogenesis: from tissues to organs o differentiation of organs from tissues involve interactions and mixing between germ layers  lots of cellular movement in the embryo o fate of ectoderm  nervous system, eye parts, epidermis o fate of endoderm (germ layer on inside)  pharynx, digestive track, liver, pancreas, urinary bladder o fate of mesoderm  dermis, bone, muscles, blood vessels, heart, kidney, gonads Neural crest o arise by delamination from the neural tube and peripheral migration o present in urochordates, where it gives ride to pigment cells o gives rise to a variety of structures in adult vertebrates o eg. gives rise to hormone-producing cells, some bone and connective tissues of the heat, etc. Placodes o arise from thickenings of the surface ectoderm and cavitation o give rise to sensory organs and receptors o note that the vertebrate head derives mostly from neural crest and placodes Maturation - juvenile  sexually mature adult (direct development) - larva  metamorphosis  sexually mature adult - larva  growth/reproduction as larva Heterochrony - change in the timing of developmental events across generations - links otogeny with phylogeny - when change are adaptive, dramatic evolutionary novelties can result from alteration of developmental timing - two major types of heterochoronies o Paedomorphosis – maintenance of juvenile characters in the adults of descendants o Peramorphosis –
More Less

Related notes for ZOO 2090

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.