1. Body Areas
copyright cmassengale

2. Body Surfaces Dorsal – back or upper surface
Ventral – belly or lower surface
Anterior – head or front end
Posterior – tail or hind end opposite the head
copyright cmassengale

3. Surfaces (Most Animals)
DORSAL
POSTERIOR
ANTERIOR
VENTRAL
copyright cmassengale

4. Symmetry
copyright cmassengale

5. Body Symmetry
Symmetry is the arrangement of body parts around a central plane or axis
Asymmetry occurs when the body can’t be divided into similar sections (sponges)
copyright cmassengale

6. Body Symmetry
copyright cmassengale

7. Radial Symmetry
Radial symmetry occurs when body parts are arranged around a central point like spokes on a wheel (echinoderms)
Most animals with radial symmetry are sessile (attached) or sedentary (move very little)
copyright cmassengale

8. Bilateral Symmetry
Occurs when animals can be divided into equal halves along a single plane
Organisms will have right and left sides that are mirror images of each other
More complex type of symmetry
Animals with bilateral symmetry are usually motile (they move)
Animals have an anterior and posterior end
Show cephalization (concentration of sensory organs on the head or anterior end)
copyright cmassengale

9. copyright cmassengale

11. Segmentation
copyright cmassengale

12. Segmentation
Occurs whenever animal bodies are divided into repeating units or segments
Found in more complex animals
Earthworms show external segmentation
Humans show internal segmentation (backbone)
copyright cmassengale

13. Body Layers
All worms, mollusks, arthropods, echinoderms, and vertebrates have three cell layers
Ectoderm
Endoderm
Mesoderm
copyright cmassengale

14. Animal Systems
copyright cmassengale

15. Basic Animal Systems Chart
Organ/Structures
Purpose and Process
Endocrine
Glands (thymus, thyroid, pancreas…)
Production of hormones. Hormones are produced in one location and arrive at another via the circulatory system.
Digestive
Mouth, esophagus, stomach, liver, small intestine, large intestine, rectum, anus
To extract nutrients from food. Mouth and stomach allow for mechanical breakdown, small intestine removes nutrients from food through diffusion, large intestine removes excess water through osmosis.
Respiratory
Trachea, lungs, diaphragm
To oxygenate blood and remove carbon dioxide. Processes occur through diffusion.
Circulatory
Heart, arteries, veins, capillaries
Provide transport of molecules through blood that is pumped through the body. Molecules move through diffusion.
Excretory
Kidneys, bladder, ureters, urethera
Remove metabolic wastes/salt/excess water to maintain homeostasis. Process are done through osmosis/diffusion.
Reproductive
Ovaries, uterus, vagina, penis, testicles
For creating offspring.

16. Digestive Systems All animals are heterotrophs (ingest their food)
Animals with a one-way digestive system have a mouth and an anus
Food enters the mouth, continues in one direction through the digestive tract, and wastes leave through the anus
Includes annelids, arthropods, & vertebrates
copyright cmassengale

17. Circulatory Systems Transports oxygen & nutrients to cells
Carries away wastes &
carbon dioxide from cells
Responds to changing demands by increasing or decreasing heart rate and blood flow in order to maintain homeostasis.
Sponges, cnidarians, & flatworms do NOT have circulatory systems
copyright cmassengale

18. Respiratory System
Helps maintain homeostasis by allowing gas exchange (intake of oxygen/release of carbon dioxide).
Responds to changing demands by increasing or decreasing breathing rate.
Gases can diffuse across moist surfaces (earthworms)
Gills filter O2 from water (aquatic animals)
Lungs take O2 from air (terrestrial animals)
Gills
copyright cmassengale

19. Excretory System
Excretion is the removal of nitrogen wastes from the body
Diffusion is used by simple aquatic animals
Terrestrial animals remove wastes with Kidneys
May be paired (most vertebrates)
copyright cmassengale

20. VERTEBRATE SYSTEMS System Description Function Skeletal
Endoskeleton of bone and/or cartilage
Provides support and protection
Muscular
Contractile tissue attached to bone or cartilage; some are part of internal organ walls
Enables animals to move; protects some organs
Integumentary
Body covering of skin, hair, nails, scales, or feathers
Provides support & protection; involved in excretion, respiration, and perception
Digestive
Tube extending from mouth to anus; includes mouth, esophagus, stomach,
intestines, rectum, liver, pancreas, and gall bladder
Prepares food for use by the animal's cells; removes solid wastes from the body
Respiratory
Gills or lungs and associated structures
Exchanges gases between the animal and it's environment
Circulatory
Closed system of blood vessels with 2, 3, or 4 chambered hearts; includes arteries, veins, capillaries, and blood
Carries blood from the heart to the rest of the body, transports gases, nutrients and wastes.
Excretory
Includes the kidneys, urinary bladder, ureters, and urethra; skin, lungs, and gills may also be involved
Removes wastes from the body
Nervous
Brain, spinal cord, nerves, and senses
Monitors the environment; controls & coordinates many body functions
Reproductive
Females - ovaries, fallopian tubes, uterus, vagina
Males - testes, prostate, penis
Produces and carries eggs & sperm;
allows for internal or external fertilization & development
Endocrine
Glands - Thyroid, parathyroid, adrenals, pancreas, gonads, and pituitary
Secretes chemicals (hormones) that regulate body growth, reproduction & development

21. Animal Reproduction
Reproduction is the process by which organisms make more of their own kind
All animals reproduce by sexual reproduction - produce eggs and sperm
Some animals also use asexual reproduction - creating identical offspring
copyright cmassengale

22. Types of Animal Asexual Reproduction
Regeneration or Fragmentation is the breaking off of pieces and the re-growth of a new organism
Found in simple animals like Sponges and Flatworms
Budding occurs in hydra whenever a growth on the parent is released
Creates a clone
copyright cmassengale

23. Parthenogenesis – females produce eggs that develop unfertilized into female organisms
Komodo dragon is an example
copyright cmassengale

24. Hermaphrodites are animals like earthworms that produce BOTH eggs and sperm
Most hermaphrodites do NOT fertilize their own eggs
Mate to exchange sperm
copyright cmassengale

25. Fertilization
External – sperm and eggs are released into water where they are fertilized
Internal – sperm and egg are fertilized inside the female animal’s body
copyright cmassengale