An Introduction to Animal Diversity Turner College & Career High School  2015

What characteristics are common to all animals? Eukaryotic cells NO cell wall Multicellular Cell specialization Heterotrophic Reproduction/Development

Categories of Animals Invertebrates: 95%; animals without backbones Sea stars, worms, jellyfish, & insects Vertebrates: 5%; animals with backbones Fish, amphibians, reptiles, birds, mammals

All About Animals What does an animal do when it respires? They take in oxygen and give off carbon dioxide. What does the excretory system of most animals do? Helps maintain homeostasis by eliminating ammonia quickly or converts it into a less toxic substance that is removed from the body. Animals respond to events in their environment using specialized cells called nerve cells.

General Characteristics Feeding: Heterotrophic, cannot make their own food. Support: Developed skeletal & muscular system. Habitat: Body evolved to suit environment. Cell: Multicellular, eukaryotic. Movement: Most are motile, but some are sessile at some point in their lives. Reproduction: Varies among the Phyla.

Types of Feeders Type of Feeder Description Herbivore Feeds on plants. Carnivore Feeds on other animals. Omnivore Feeds on both plants and animals. Filter feeder Aquatic; strain tiny floating organisms from the water. Detritivores Feeds on decaying plant and animal material.

Support Exoskeleton: a rigid external covering for the body in some vertebrate animals, providing both support and protection. Endoskeleton: an internal skeleton, such as the bony or cartilaginous skeleton of vertebrates.

Body Cavities Body cavity may be present or absent or false. Coelomate – cavity present. Pseudocoelomate – false cavity present. Acoelomate – no cavity present. Coelom protects organs, body, etc.

Coelomates Coelomates: “true-coelom”. Have a fluid-filled space separating digestive tract from outer covering. Space forms from the MESODERM.

Pseudocoelom Pseudocoelom: “false coelom”. Body cavity derived from the blastocoel, NOT from mesoderm.

Acoelomates Acoelomates: Organisms without body cavities.

Animal Symmetry Bilaterally symmetrical animals have: Dorsal (top) side and Ventral (bottom) side Anterior (head) and Posterior (tail) ends Cephalization - the development of a head

Advantages of Segmentation Segmentation allows different body regions to develop for different purposes or uses. Efficient movement Detect prey Specialization

Animal Mobility Motile: ability to move. What enables motile animals to move around? Muscular contractions, usually in combination with support of the skeletal system. Sessile: stationary in adult life form. Why do sessile animals need musculature? Muscles help sedentary animals feed and pump water and fluids through their bodies. Filter feeders: strain tiny floating organisms from the water.

Animal Reproduction What type of reproduction maintains genetic diversity in populations? How? Sexual reproduction; by improving species’ ability to evolve when the environment changes therefore increasing their chance of survival. What does asexual reproduction allow an animal to do? It allows animals to increase their numbers rapidly therefore increasing their chance of survival. Types include: binary fission, budding, fragmentation, parthenogenesis.

Early Development of Animals What is another name for a fertilized egg? Zygote What does a zygote form after it undergoes a series of divisions? Blastula Protostome: development of an organism from mouth to tail. (ex. Invertebrates). Deuterostome: development of an organism from tail to mouth. (ex. vertebrates.).

Reproduction Sperm fertilizes an egg  zygote.

Development Sperm fertilizes an egg  zygote. Zygote undergoes cleavage. Mitotic cell division and cytokinesis, but NO cell growth

Development Zygote  Cleavage  Blastula (hollow space inside = Blastocoel)

Development Zygote Cleavage Blastula  Gastrula Gastrulation

Organization of Tissues Gastrulation  Animal embryos form germ layers: Ectoderm  outer covering/not seen in some Mesoderm  middle layer: muscles and all other organs Endoderm  innermost layer: lines digestive tract, liver and lungs

Body Symmetry Symmetry in biology is the balanced distribution of duplicate body parts or shapes. Radial symmetry: body parts that repeat around the center. Bilateral symmetry: a single plane divides the body into to equal parts. Asymmetry: irregular shape. Ex: Lobster Ex: Sea Anemone

Comparing vertebrates: digestive system Class Unichordata Class Reptilia Class Mammalia Class Chondrichthyes Class Aves

Comparing vertebrates: Respiratory system Class Amphibia Class Reptilia Class Mammalia Class Aves Pg. 1001 Pg. 863

Comparing vertebrates: circulatory system Pg. 824 Pg. 854 Pg. 885

Comparing vertebrates: Nervous system Pg. 886

Evolutionary cladogram Non-vertebrates: Urochordata Class Agnatha: Jawless fish Class Chondrichthyes: Sharks Class Osteichthyes: Bony fish Class Amphibia: Amphibians Class Reptilia: Reptiles Class Aves: Birds Class Mammalia: Mammals