3.3 Animals

Kingdom Animalia

Animals

* Multicellular
* Eukaryotic 
* Heterotrophic


* __**Two types of tissues that are only found in animals:**__ 
* Nervous system tissue
* Muscle tissue


* Most reproduce sexually
* Most are mobile

Classifying Animals

* Since animals share so many common characteristics, we classify them based on other homologies (similar traits)


* Animals are characterized based on **body plan** (the layout of their body structures)
* Symmetry
* Organization of body tissues
* Other physiological modifications of body parts

Bilateral vs Radial Symmetry

**Radial** is symmetrical along any plane through central axis wheres as **Bilateral** is single line of symmetry with left/right sides

Chordata (vertebrates) Include:

jawless fish ex lamprey, Cartilaginous fish ex. Shark and bony fish ex tuna

Vertebrates

Backbone supports a delicate central nerve cord and anterior brain

Internal Skeleton

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* Can grow bigger than arthropods
* Can move in more complex ways
* Anterior skull contains and protects brain
* Extends past the anus to tail

Internal Skeleton (2)

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* Gills (aquatic) or lungs (terrestrial)
* Ventral heart
* Closed circulatory system

Cell specialization germ layers

* **Germ Layers** – layers of cells in a developing embryo that give rise to specialized tissues
* Ectoderm
* Mesoderm
* Endoderm


* **Coelom** – body cavity

Present in some animals

Contains the organs Develops from mesoderm

examples

sea stars, sea urchins, earthworms, sponges, jellyfish, lobsters, crabs, insects, spiders, snails, clams, and squid.J

Classes Chordata

Craniata (fish, amphibians, reptiles, birds, and mammals); Tunicata or Urochordata (sea squirts, salps); and Cephalochordata (which includes lancelets).

Phylum Chordata

fish, amphibians, reptiles, birds, and mammals.