Kingdom AnimaliaKingdom AnimaliaMajor Animal PhylaMajor Animal Phyla

PoriferaCnidariaPhatyhelminthesNematodaRotifera

MolluscaAnnelidaArthropodaEchinodermataChordata

Major Chordata classesMajor Chordata classes

AgnathaChondrichthyesOstiechthyesAmphibianReptiliaAves Mammalia

Major Mammalia OrdersMajor Mammalia Orders

MonotremesMarsupialsPlacentals

Essential Functions Essential Functions of Animal Lifeof Animal Life

Feeding (Digestive system)Respiration (Respiratory system)Internal transport (Circulatory system)Excretion (Excretory system)Response (Nervous sysytem)Movement (Skeletal/ Muscular sysytem)

Kingdom AnimaliaKingdom Animalia

All animals are multicellular. All animals are heterotrophic. Dominant generation in the life cycle is the

diploid generation. Most animals are motile during at least some part

of their life cycle. Most animals undergo a period of embryonic

development during which two or three layers of tissues form.

Animal DiversityAnimal Diversityvariations in the following characteristicsvariations in the following characteristics

Tissue complexity– Eumetazoa- cells organized into tissues

Three germ layers– Ectoderm- outer layer– Mesoderm- middle layer– Endoderm- inner layer

Diploblastic- two germ layers Triploblastic- three germ layers

– Parazoa- cells are not organized into true tissues and organs do not develop.

Embryonic DevelopmentEmbryonic Development

Fertilization Cleavage

– Zygote begins a series of cleavage divisions, rapid cell divisions without cell growth.

– Blastomeres = resulting cells Morula= solid ball of cells from successive

cleavage divisions Blastula= liquid fills the morula creating a

hollow sphere of cells.– Cavity is called blastocoel.

Embryonic DevelopmentEmbryonic Development

Gastrula (gastrulation)– Occurs when a group of cells move inward

into the blastula.– Forming a two-layer embryo with an

opening from the outside into a center cavity– Third layer forms between the outer layer

and inner layer. Ectoderm, mesoderm, endoderm

Embryonic DevelopmentEmbryonic Development

– Archenteron Center cavity formed by gastrulation Completely surrounded by endoderm cells

– Blastopore Opening into the archenteron It becomes the mouth in protostomes It becomes the anus in deutrostomes

Embryonic DevelopmentEmbryonic Development

Extraembryonic membrane development– In birds, reptiles, and mammals– Chorion – outer membrane

Birds & reptiles it acts as a membrane for gas exchange

Mammals- it implants into the endometrium and later together with maternal tissue, forms the placenta.

– Placenta- gases, nutrients, and wastes are exchanged

Embryonic DevelopmentEmbryonic Development

– Amnion- encloses the amniotic cavity, a fluid-filled cavity that cushions the developing embryo.

– Yolk sac- birds and reptiles Membrane that digests the enclosed yolk Blood vessels transfer the nutrients to the

developing embryo

Embryonic DevelopmentEmbryonic Development

Organogenesis– Cells continue to divide after gastrulation and start to

differentiation (cell differentiation)– Development of organs is organogenesis.– Chordate characteristics

Notochord- stiff rod that provide support in lower chordates– Cells along the dorsal surface of the mesoderm germ layer form the

notochord.– In higher chordates, the vertebrea are formed from nearby cells in the

mesoderm Neural tube- formed from ectodermal cells directly above the notochord

– Neural plate is formed first, indents forming the neural groove, then rolls up into a cylinder, the neural tube.

– The neural tube develops into the Central nervous System

Embryonic DevelopmentEmbryonic Development

Ectoderm– Skin, Nervous system, Teeth, Bones

Endoderm– Digestive tract and organs derived from it, such as the

liver and lungs of vertebrates

Mesoderm– Muscles and most other organs between the digestive

tube and the outer covering of the animal

Animal DiversityAnimal Diversityvariations in the following characteristicsvariations in the following characteristics

Body Symmetry– Radial symmetry

Only one orientation– Front and Back or Top and Bottom

Circular body patterns

– Bilateral symmetry Dorsal (top) Ventral (bottom) Anterior (head) Posterior (tail)

Animal DiversityAnimal Diversityvariations in the following characteristicsvariations in the following characteristics

Cephalization– A progressively greater increase in nerve

tissue concentration at the anterior end (head) as organisms increase in complexity

– Example Brains have developed with accessory sensory

organs for seeing, smelling, tasting, and feeling.

Animal DiversityAnimal Diversityvariations in the following characteristicsvariations in the following characteristics

Gastrovascular cavity– Areas where food is digested– One opening– Two openings

Digestive tract

Animal DiversityAnimal Diversityvariations in the following characteristicsvariations in the following characteristics

Coelom– A fluid-filled cavity that develops from

mesodermal tissue during embryonic development in more advanced animals.

– Cushions the internal organs and allows for their expansion and contraction.

– Acoelomate- lack a coelom– Pseudocoelomate- cavity that is not completely

lined by mesoderm-derived tissue.

Animal DiversityAnimal Diversityvariations in the following characteristicsvariations in the following characteristics

Segmentation– Segmented body parts

Animal DiversityAnimal Diversityvariations in the following characteristicsvariations in the following characteristics

Characteristics Protostome Deuterostome

Early cleavages Slight angle

(spiral cleavage)

Straight down

(radial cleavage)

First infolding of archenteron forms

mouth anus

Coelom develops from

Split in tissue at sides of anchenteron

Outpounching of archenteron

wall