AP Biology Slides Chapter 32
AP Biology Slides Chapter 32
AP Biology Slides Chapter 32
32
An Introduction to Animal
Diversity
Biology
Eighth Edition
Neil Campbell and Jane Reece
Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp
Copyright 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Animals Overview
Animals are multicellular, heterotrophic eukaryotes
with tissues that develop from embryonic layers.
Blastocoel
Cleavage
Endoderm
Blastula
Ectoderm
Zygote
Eight-cell stage
Gastrulation
Blastocoel
Cross section
of blastula
Archenteron
Gastrula
Blastopore
Individual
choanoflagellate
Choanoflagellates
OTHER
EUKARYOTES
Sponges
Animals
Collar cell
(choanocyte)
Other animals
1.5 cm
0.4 cm
A Cambrian seascape
Body Cavities
Coelom
Triploblastic
Animals Body
Cavities
Body covering
(from ectoderm)
Digestive tract
(from endoderm)
(a)
Muscle layer
(from
mesoderm)
Digestive tract
(from endoderm)
(b)
Pseudocoelomate
Body covering
(from ectoderm)
Tissuefilled region
(from
mesoderm)
Cleavage:
protostome or deuterostome development
In protostome development, cleavage is spiral
and determinate.
In deuterostome development, cleavage is
radial and indeterminate.
With indeterminate cleavage, each cell in the
early stages of cleavage retains the capacity to
develop into a complete embryo.
Indeterminate cleavage makes possible
identical twins, and embryonic stem cells.
Copyright 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Protostome
Deuterostome
Development
molluscs, annelids
Development
echinoderm, chordates
Eight-cell stage
(a) Cleavage
Eight-cell stage
Coelom
Ectoderm
Mesoderm
Endoderm
Blastopore
Blastopore
Mesoderm
Folds of archenteron
form coelom.
Mouth
Digestive tube
Mouth
Mouth develops from blastopore.
Anus
Porifera
Eumetazoa
Metazoa
ANCESTRAL
COLONIAL
FLAGELLATE
Cnidaria
Ctenophora
Deuterostomia
Bilateria
Brachiopoda
Echinodermata
Chordata
Platyhelminthes
Protostomia
Ectoprocta
Rotifera
Mollusca
Annelida
Arthropoda
Nematoda
Porifera
Metazoa
Cnidaria
Acoela
Deuterostomia
Bilateria
Echinodermata
Chordata
Platyhelminthes
Lophotrochozoa
Rotifera
Ectoprocta
Brachiopoda
Mollusca
Annelida
Ecdysozoa
A view of animal
phylogeny based mainly
on molecular data
Calcarea
Ctenophora
Eumetazoa
ANCESTRAL
COLONIAL
FLAGELLATE
Silicea
Nematoda
Arthropoda
Points of Agreement
All animals share a common ancestor.
Sponges are basal animals.
Eumetazoa is a clade of animals eumetazoans with true tissues.
Most animal phyla belong to the clade Bilateria,
and are called bilaterians.
Chordates and some other phyla belong to the
clade Deuterostomia.
Copyright 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Lophotrochozoans Characteristics
Lophophore
Apical tuft
of cilia
100 m
Mouth
(a) An ectoproct
Anus
(b) Structure of a trochophore
larva
Animal Phylogeny
Common ancestor
of all animals
Metazoa
Sponges
(basal animals)
Eumetazoa
Ctenophora
Cnidaria
Acoela (basal
bilaterians)
Deuterostomia
Bilateral
summetry
Three germ
layers
Lophotrochozoa
Ecdysozoa
True
tissues