Correlative Body Systems

Body Temperature Regulation Endothermy Using energy generated by metabolism (mitochondria) to regulate and maintain temperature Ectothermy The use of external thermal energy to regulate and maintain temperature

Body Temperature Regulation

Surface-to-Volume Ratio Alveoli Villi and Microvilli

Interactions and Coordination Gas Exchange and Respiratory systems

Interactions and Coordination Gas Exchange

Interactions and Coordination

Interactions and Coordination

Interactions and Coordination Circulatory and Respiratory

Obtaining Nutrients Digestive Systems

Obtaining Nutrients Interactions and Coordination

Obtaining Nutrients Regulation

Eliminating Wastes Nitrogenous waste

Eliminating Wastes

Eliminating Wastes

Homeostatic Control Osmoregulation

Muscular

Interactions and Coordination

Cortical granule release (cortical reaction) Fig. 47-UN1 Sperm-egg fusion and depolarization of egg membrane (fast block to polyspermy) Cortical granule release (cortical reaction) Formation of fertilization envelope (slow block to polyspermy)

2-cell stage forming Animal pole 8-cell stage Vegetal pole Blastocoel Fig. 47-UN2 2-cell stage forming Animal pole 8-cell stage Vegetal pole Blastocoel Blastula

Fig. 47-UN3

Fig. 47-UN4 Neural tube Neural tube Notochord Notochord Coelom Coelom

Fig. 47-UN5 Species: Stage:

Fig. 47-UN6

Body Cavities Most triploblastic animals possess a body cavity A true body cavity is called a coelom and is derived from mesoderm Coelomates are animals that possess a true coelom

Fig. 32-8 Coelom Body covering (from ectoderm) Tissue layer lining coelom and suspending internal organs (from mesoderm) Digestive tract (from endoderm) (a) Coelomate Body covering (from ectoderm) Pseudocoelom Muscle layer (from mesoderm) Digestive tract (from endoderm) (b) Pseudocoelomate Figure 32.8 Body cavities of triploblastic animals Body covering (from ectoderm) Tissue- filled region (from mesoderm) Wall of digestive cavity (from endoderm) (c) Acoelomate

Coelom Body covering (from ectoderm) Tissue layer lining coelom Fig. 32-8a Coelom Body covering (from ectoderm) Tissue layer lining coelom and suspending internal organs (from mesoderm) Digestive tract (from endoderm) Figure 32.8a Body cavities of triploblastic animals (a) Coelomate

A pseudocoelom is a body cavity derived from the mesoderm and endoderm Triploblastic animals that possess a pseudocoelom are called pseudocoelomates

Body covering (from ectoderm) Pseudocoelom Muscle layer (from Fig. 32-8b Body covering (from ectoderm) Pseudocoelom Muscle layer (from mesoderm) Digestive tract (from endoderm) Figure 32.8b Body cavities of triploblastic animals (b) Pseudocoelomate

Triploblastic animals that lack a body cavity are called acoelomates

Wall of digestive cavity (from endoderm) Fig. 32-8c Body covering (from ectoderm) Tissue- filled region (from mesoderm) Wall of digestive cavity (from endoderm) Figure 32.8c Body cavities of triploblastic animals (c) Acoelomate

Protostome and Deuterostome Development Based on early development, many animals can be categorized as having protostome development or deuterostome development

Cleavage 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

Protostome development Deuterostome development (examples: echinoderm, Fig. 32-9 Protostome development (examples: molluscs, annelids) Deuterostome development (examples: echinoderm, chordates) (a) Cleavage Eight-cell stage Eight-cell stage Spiral and determinate Radial and indeterminate Key (b) Coelom formation Coelom Ectoderm Mesoderm Archenteron Endoderm Coelom Mesoderm Blastopore Blastopore Mesoderm Solid masses of mesoderm split and form coelom. Folds of archenteron form coelom. Figure 32.9 A comparison of protostome and deuterostome development (c) Fate of the blastopore Anus Mouth Digestive tube Mouth Anus Mouth develops from blastopore. Anus develops from blastopore.

Protostome development (examples: molluscs, annelids) Fig. 32-9a Protostome development (examples: molluscs, annelids) Deuterostome development (examples: echinoderms, chordates) (a) Cleavage Eight-cell stage Eight-cell stage Figure 32.9a A comparison of protostome and deuterostome development Spiral and determinate Radial and indeterminate

Coelom Formation In protostome development, the splitting of solid masses of mesoderm forms the coelom In deuterostome development, the mesoderm buds from the wall of the archenteron to form the coelom

Protostome development (examples: molluscs, annelids) Fig. 32-9b Protostome development (examples: molluscs, annelids) Deuterostome development (examples: echinoderms, chordates) (b) Coelom formation Coelom Key Ectoderm Archenteron Mesoderm Endoderm Coelom Mesoderm Blastopore Blastopore Mesoderm Figure 32.9b A comparison of protostome and deuterostome development Solid masses of mesoderm split and form coelom. Folds of archenteron form coelom.

Fate of the Blastopore The blastopore forms during gastrulation and connects the archenteron to the exterior of the gastrula In protostome development, the blastopore becomes the mouth In deuterostome development, the blastopore becomes the anus

Protostome development (examples: molluscs, annelids) Fig. 32-9c Protostome development (examples: molluscs, annelids) Deuterostome development (examples: echinoderms, chordates) (c) Fate of the blastopore Anus Mouth Key Ectoderm Digestive tube Mesoderm Endoderm Figure 32.9c A comparison of protostome and deuterostome development Mouth Anus Mouth develops from blastopore. Anus develops from blastopore.

Concept 32.4: New views of animal phylogeny are emerging from molecular data Zoologists recognize about three dozen animal phyla Current debate in animal systematics has led to the development of two phylogenetic hypotheses, but others exist as well

One hypothesis of animal phylogeny is based mainly on morphological and developmental comparisons

“Porifera” Cnidaria Metazoa ANCESTRAL COLONIAL FLAGELLATE Ctenophora Fig. 32-10 “Porifera” Cnidaria ANCESTRAL COLONIAL FLAGELLATE Metazoa Ctenophora Eumetazoa Ectoprocta Brachiopoda Deuterostomia Echinodermata Chordata Bilateria Platyhelminthes Rotifera Figure 32.10 A view of animal phylogeny based mainly on morphological and developmental comparisons Protostomia Mollusca Annelida Arthropoda Nematoda

One hypothesis of animal phylogeny is based mainly on molecular data

Silicea “Porifera” Metazoa Calcarea ANCESTRAL COLONIAL FLAGELLATE Fig. 32-11 Silicea “Porifera” Calcarea ANCESTRAL COLONIAL FLAGELLATE Metazoa Ctenophora Cnidaria Eumetazoa Acoela Echinodermata Deuterostomia Chordata Bilateria Platyhelminthes Rotifera Ectoprocta Lophotrochozoa Figure 32.11 A view of animal phylogeny based mainly on molecular data Brachiopoda Mollusca Annelida Nematoda Ecdysozoa Arthropoda