Animals

Heterotrophs

Means eating different foods - can’t make their own food just go out and find / gather

Main consideration of heterotrophs

Finding food and avoiding becoming food

Symmetry

Asymmetry - eg. Sponges

Radial symmetry - can cut through centre line on any plane and have same halves (eg. Coral, jellyfish, sea anemone)

Bilateral symmetry - can cut sagittally and have two of the same halves (vertebrates)

Bilateria Characteristics

Have different holes for eating and excreting food (mouth and anus), front end of body has sensory receptors (eyes, mouth, nose, ears)

Protostomes

First hole created embryonically is the mouth (eg. Octopus, squid, insects)

Deuterostomes

First hole created embryonically is the anus (eg. Vertebrates, sea urchins, starfish)

tissues

Important for going out and catching food (gut cells break down food, etc)

Diploblastic : two layers of tissue (eg. Jellyfish)

Triploblastic : three layers of tissues (endoderm, ectoderm, mesoderm)

Body cavities

Spaces in body that allow more movement → seen in bilaterians (eg. Gut can move around and digest food)

Radial cleavage

Splitting down the middle (deuterosome)

Spiral cleavage

Splitting and twisting (protostome)

Gastrulation

Differs between protostomes and Deuterostomes → determines if mouth or anus is made first (important in establishing animals)

Arthropods

Most diverse group of animals

Insects are the most diverse group of arthropods and organisms on earth: narrow niches, short lifespan, fast reproductive rate

Chordates

Animals with vertebrae

First chordate was pikaia - 500 million years old → have a mouth and tube for food, a tail that extends past anus so they can swim strongly

Most animals are chordates

Notochord

Thick supporting rod - becomes intervertebral discs, runs from head to tail

Springy force - allows movement

Pharynx

Has holes that allows water to leave, becomes mouth and throat

Throat in humans and mouth in fish - efficient for fish to get oxygen into body (gills)

Dorsal Hollow Nerve Chord

Has cerebrospinal fluid that runs to brain and transport oxygen to brain

Identifying structures of chordates

Notochord, segmented muscles, dorsal hollow nerve chord, postanal tail, pharynx

Vertebrates characteristics

Has important features for sensory processing and sensory ability on front of face (mouth, nose, eyes, ears), make up most of large animals in global ecosystem, adaptation/evolution was for sensing environment to get food

Vertebrates adaptations

Locomotor - flight, ability to walk on land)

Sensory - echolocation