- Ventricle
- Aorta
- Pulmonary artery
- Vena cava
No category found.
- Ray-finned fish
- Lobe-finned fish
- Cartilaginous fish
- Jawless fish
- Digestion
- Locomotion
- Respiration
- Sensory perception
- Ophiuroidea
- Echinoidea
- Asteroidea
- Holothuroidea
- A bilaterally symmetrical shell
- A coiled shell
- The anus opening near the mouth
- Loss of the radula
- Hexapoda
- Crustacea
- Chelicerata
- Myriapoda
- Ascaris
- Pinworm
- Filarial worm
- Hookworm
- Hydrozoa
- Scyphozoa
- Anthozoa
- Cubozoa
- Locomotion
- Reproduction
- Filter feeding and gas exchange
- Defense
- Fully developed young born after long gestation
- Larval stage in water
- Eggs laid in nests
- Underdeveloped young complete development in a pouch
- Alveoli
- Bronchioles
- Air sacs
- Gills
- Swallowing prey
- Delivering venom
- Olfaction (smelling)
- Locomotion
- Cold temperatures
- Food scarcity
- Drought conditions
- Predation
- Sharks and rays
- Tuna and salmon
- Lampreys and hagfish
- Frogs and toads
- Dorsal hollow nerve cord
- Ventral solid nerve cord
- Multiple nerve cords
- A diffuse nerve net
- Asteroidea
- Ophiuroidea
- Crinoidea
- Echinoidea
- Filter feeding
- Piercing prey
- Scraping food
- Capturing prey
- A single pair of legs per segment
- Two pairs of legs per segment
- Three pairs of legs per segment
- No legs
