Nervous System
Nervous System
Mollusk
Scallops- 3 nervous centers, no brain, they contain sensory cells, but no sensory organs.
Slugs- contain sensory organs, they have eyes. The tentacles contain most of their sensory organs. Octopi- highly complex nervous systems, brains, eyes, etc. They also have neurons in their cells, making them fast.
Amphibians Nervous System- Frogs have two centers, brain and spinal cords. The brain can split up into three parts, Forebrain, contains the sense of smell, controlled by olfactory lobes.
midBrain- optic lobes that control sight. HindBrain- contains cerebellum and medulla oblongata cerebellum helps maintain balance and equilibrium in the frog, medulla oblongata helps in the regulation of respiration, digestion and other automatic functions which helps transport info.
Arthropods- contains brain, and 2 centers, brain and spinal cords. common sensory organs to
a mammal.
Mammals- highly developed brain and sensory organs as eyes, nose, mouth, ears, and touch. The spinal cord acts as a highway to the brain and sends and receives signals from the rest of the body. these signals travel through nerve endings or receptors to neurotransmitters in the brain that allow feeling. Mammals have a central nervous system (spine and brain) and a peripheral nervous system that conducts basically everything else in the body. Without this system, you could run up in front of a tiger and poke it in the face multiple times without it reacting.
echinoderms- no brains- contain nerves running from mouth to each arm, tiny eyespots that detect light and dark, their tube feet are sensitive to chemicals and smells they lack the advanced nervous system of chordates http://w3.shorecrest.org/~Lisa_Peck/MarineBio/syllabus/ch7invertebrates/Invertwp/2007/tj/nerv.html
Reptiles- Reptiles share the similar structure of brain with Amphibians, except the cerebrum and cerebellum are slightly larger. most typical sense organs are well developed with certain exceptions most notably in snakes lack of external ears, there are twelve pairs of cranial nerves.Due to their short cochlea, reptiles use electrical turning to expand their range of audible frequency. Reptiles are generally considered less intelligent than mammals and birds the size of their brain relative to their body is much less than that of mammals. Larger lizards like the monitors are known to exhibit complex behavior including cooperation
annelids- primitive brain,located in head region and central nervous the central nerve that runs down the length ot the worm. The nervous system connects the primitive brain, or ganglionic mass, located in the head region, to a ring of nerves on a ventral nerve cord that runs the length of the body; the cord gives rise to lateral nerves and ganglia in each segment. Sense organs of annelids generally include eyes, taste buds, tactile tentacles, and organs of equilibrium called statocysts
