Bio 108 - Lecture 16 Flashcards
5 Characteristics of Kingdom Animalia
1) Multicelular
2) Lack cell walls
3) Chemoheterotrophs
4) Sexual
5) Animate
4 Characteristics unique to Animals
1) Extracellular Collagen
2) 3 Unique types of intercellular Junction
3) Homeobox Genes
4) Hox Genes
3 Types of intercellular Junctions
1) Tight Junctions
2) Desmosomes
3) Gap Junctions
Anisogamy
An =
Iso =
- Small motile sperm, large nonmotile egg
An = Not
Iso= Same
What is Cleavage?
When a diploid zygote undergoes a number of mitotic cell divisions
What is a Blastula?
Blast = ?
A hollow ball of cells made from cleavage
Blast = Sprout, germinate
What is gastrulation
Gaster =
When the blastula invaginated at one end
Gaster = Stomach
What are the two layers of cells the Gastrula has?
Ectoderm
Endoderm
Derm = Skin
Direct vs Indirect Development
Direct: Embyro continues gradually on towards adult form
Indirect: Involves intervening (Larvae) stages who’s morphology differs greatly from sexually mature adult step
The three splits in Traditional Tree
1) Split based on precedes of True Tissue
2) Split based on symmetry
3) Split based on embryonic development of bilateria
Animals With / Without True Tissue
Without: Sponges and Placozoans
With: Eumetazoa (all other animals)
Radial vs Bilateral Symmetry
Radia: Has top and bottom but no left or right
Bilateral: Has top, bottom, left and right
What are Bilateria?
The clade of Bilaterally Symmetrical animals
Characteristics of Bilateria
- Tripoblastic
- Some have hollow fluid filled body cavity
- Some have solidly packed with no body cavity (Acoelomates)
What are Acoelomates?
coel =
Bilaterians that are solidly packed with no body cavity
Coel = Cavity, Hollow
Cavity + Group
Eucoelomates
Pseudoelomate
Eucoelomate Characteristics
Have a body cavity that is completely lines with mesoderm ally derived tissues
Pseudoelomate
Animals lack complete mesodermal lining
3 Functions of Cavity + Group
- Cushions Internal Organs
- Allows internal organs to shift without deforming the outside body
- Fluid filled cavity can be used as hydrostatic skeleton
Characteristics of Protostomia
- First invagination of the gastrula becomes the mouth
- Has Spiral cleavage
- Cleavage is determinate
- Solid blocks of mesoderm split internally to create fluid filled hollows
Characteristics of Deuterostomia
- The second invagination becomes the mouth
- Radial Cleavage
- Cleavage is indeterminate
- Mesoderm at one end pinches off to make fluid filled hollows
Radial Cleavage vs Spiral Cleavage
Radial cleavage grows one on top of each other
Spiral cleavage grows in a spiral
Schizocoely
Schiz =
In Protos, solid blocks of mesoderm split internally to create fluid filled hollows
Schiz = Split
Enterocoely
Entero =
In Deuteros when mesoderm at one end of embryonic gut, the out pocketing of the mesoderm pinch off to make fluid filled hollows
Entero = Gut
