UTA - Zoology Exam 3

Who came up with the primary organizer?

Germans: Hans Spemann & Hilde Mangold

What is the primary organizer?

Tissue induction of a salamander that results in new organism

Preformation

The entire organism was inside egg or sperm.

Epigenesis

An egg contains building material and it's activated by sperm

Vitelline membrane

Membrane that hardens after creating osmotic pressure and washing away sperm in Slow Block.

Blastomere

Small, bunch of cells that only divide and do not grow.

Isolecithial

Little yolk, evenly distributed

Mesolecithial

Little yolk at vegetal pole

Telolecithial

A lot of yolk at vegetal pole

Centrolecithial

Large and central yolk.

Meroblastic cleavage

Cells it on to of undivided yolk

Holoblastic cleavage

Cleavage extends through entire egg

Direct vs Indirect development

Direct - small organism

Indirect - larva stages

Matrotrophy

Mother nourishes the developing embryo

Blastula

Hallow cluster of cells. Blastocoel. 1 layer

Gastrulation

Formation of 2 layers

Archenteron

Internal pouch formed be gastrula

Blastopore

Opening to archentero

Primary germ cell layers

Ectoderm- Integument & nervous system

Endoderm-GI trac & internal organs

Mesoderm-Connective tissue, fluids & muscles.

Formation of coelom

Schizocoely

Enterocoely

Driesch

Urchin grinding & shaking

Dolly the sheep

Cloned sheep. Didn't look like surrogate mother.

Induction

Cells evoking a developmental response in other cells

Primary Induction

From the dorsal lip. Last chance to make a whole new organism.

Second Induction

Other cells originate later from other inductions

Pluripoten

Stem Cells

Primitive Streak

Center of early embryonic growth in many animals.

Synctium

When a single cell membrane surrounds multiple nuclei

Metamerism

Division of the body into distinct segments

HOX genes

Equal in all animals

Protostome

Blastopore becomes mouth

Deuterostome

Blastopore becomes anus

Mosaic vs. regulative cleavege

4 cells Mosaic- mulusk. Partial embryos

Regulative-4 identical embrios. Us. twins

Schizocoely

Splitting of mesoder

Enterocoely

Pinch off.

Spiral cleavage

Blastomeres cleave oblique

Radial cleavega

Symmetrical looking embryo

Bilateral cleavage

Cleavage is a mirrior imag. Ascidians

Rotational cleavage

Divide at different times. Sometime perpendicular

Discoidal cleavage

On top of yolk

4 extraembryonic membranes

-Amnion-aqueous

-Chorion-Final enclosure

-Allantosis-Waste

-Yolk-Nourishment

Types of mammals

-Monotremes - Platypus

-Marsupials

-Placentals

Lophophora

Ectoprocta

Brachipoda

Phoronida

Prosobranchia

Parafilateic

Opistho

Parailetic

All snails

Monophyletic

Class Cephalopod

Subclass Nautiloidea

Subclass Ammonoidea

Subclass Coeloidea

Phylum Gnathostomulida

Jaw worms

Phylum Micrognathozoa

Monotypic. Limnognathia maerkis.

Phylum Rotifera

Bdelloidea

Monogomata

Seisoidea

Phylum Acnathocephala

Spine probosis.

Phylum Cycliophora

acoelomate. U shape digestive. Chorcoid

Phylum Gastrotrichia

Stomach hair. Selenocytes. Hermaphroditic. digestive system

Phylum ENtoprocta

anus within.

Phylum ectoprocta

Lophophores to filter feed

Phylum brachiopoda

Phylum Molusca

Classes:

caudofoveata

solenogastres

polyplacophora

Monoplacophora

gastropoda

cephalopoda

bivalvia

scaphopoda

Conshiera

Monoplacophora

bivalvia

scaphopoda

gastropoda

cephalopoda