Animal Systems Page 738: Body Symmetry & Chapters 27 through 28

What is an animal? Scientific Definition Animal: eukaryotes that are multicellular heterotrophs that do not have a cell wall. CharacteristicSo the are not… EukaryoticProkaryotes (Bacteria or Archaea) MulticellularProtists HeterotrophicPlants and algae Absent Cell WallPlants, algae, or fungi

FYI… 3-30 million species 97% of all species are invertebrates Invertebrates

The vast majority of animals are Arthropods (1,170,000 to 10 million species) Of all invertebrates, the insects (part of the arthropods) are by far the most numerous. About 1-30 million+ species For comparison, chordates (including mammals) consist of about 75,000 species Arthropods Chordates Arthro  + pod  Arthropod “jointed” + “foot” or “leg”  “jointed leg”

Some terms used to describe animals

Body Symmetry Asymmetrical = without symmetry Radial Symmetry = symmetry around a central axis Bilateral Symmetry – can be divided into symmetrical halves on either side of a plane

Examples of Asymmetrical Animals Porifera (Sponges) This is a cut out piece for marketing uniformity

Radial Symmetry

Animals with Radial Symmetry

Examples of Animals with Bilateral Symmetry

Body Orientation (used in humans) The Anatomical Position: The anatomical position describes a person that is standing erect with the feet facing forwards, arms hanging to the sides, and the palms of the hands facing forward. Directional terms are always from the patient’s perspective. When we refer to the right side we are referring to the patient’s right side Do not let this intimidate you… =

Body Planes of Animals (including humans) TermDefinition Sagittal (or Median) Divides the body into right and left halves Frontal (or Coronal) Divides the body into anterior and posterior halves Transverse (or Horizontal) Divides the body into superior and inferior halves

Directional Terms Right and left – Refers to the Patient’s right or left side Proximal – Near, closer to the origin Distal – Away from, farther from the origin Lateral – Toward the side, away from the mid-line Medial – Toward the mid-line, middle, away from the side

Directional Terms Superior – Above, Over Inferior – Below, Under Anterior – In front of, front Posterior – Behind, toward the rear Ventral – Toward the belly Dorsal – Toward the back

Directional Terms Quick Check TermDefinition 1Superior 2Inferior 3Anterior 4Posterior 5Lateral 6Medial 7Proximal 8Distal 9Ventral 10Dorsal

Directional Terms Quick Check TermDefinition 1SuperiorAbove, Over 2InferiorBelow, Under 3AnteriorIn front of, front 4PosteriorBehind, toward the rear 5LateralToward the side, away from the mid-line 6Medial Toward the mid-line, middle, away from the side 7ProximalNear, closer to the origin 8DistalAway from, farther from the origin 9VentralToward the belly 10DorsalToward the back

Other animal examples…

Vocabulary 1.Anatomical Position 2.Anterior 3.Asymmetrical 4.Bilateral Symmetry 5.Distal 6.Dorsal 7.Frontal (or Coronal) 8.Inferior 9.Lateral 10.Medial 11.Posterior 12.Proximal 13.Radial Symmetry 14.Right and left 15.Sagittal (or Median) 16.Superior 17.Transverse (or Horizontal) 18.Ventral

Due tomorrow at the beginning of class: 1.Write a story using seven of these words (as they are used in biology) EXCLUDING right and left. 2.No definitions in your story. 3.I must be able to tell that you know what the word means from the story. 4.No more than one vocabulary word in a sentence. 5.If I can’t read your handwriting, I wont. In other words TYPE IT or write legibly. 6.No legible first name, last name, OR period = LATE