Biopsychology

1. Neurons and glial cells

It is the part of the peripheral nervous system that interacts with the external environment. It is composed of afferent nerves that carry sensory signals from the skin, skeletal muscles, joints, eyes, ears, and so on, to the nervous system, and the efferent nerves that carry motor signals from the central nervous system to the skeletal muscles.

It is the part os the peripheral nervous system that regulates the body's internal environment. It is composed of afferent nerves that carry sensory signals from the internal organs to the CNS and efferent nerves that carry motor signals from the CNS to internal organs.

They are those autonomic motor nerves that project from the CNS in the lumbar(small of the back) and thoracic(Chest area) regions of the spinal cord.Parasympathetic: are those autonomic motor nerves that project from the brain and sacral(lower back) region of the spinal cord.

1.) Sympathetic nerves stimulate, organize, and mobilize energy resources in threatening situations, whereas parasympathetic nerves act to conserve energy;2.) Each autonomic target organ receives opposing sympathetic and parasympathetic input, and its activity is thus controlled by relative levels of sympathetic and parasympathetic activity3.) Sympathetic changes are indicative of psychological arousal, whereas parasympathetic changes are indicative of psychological relaxation.

The 12 pairs of cranial nerves, which project from the brain. The cranial nerves include purely sensory nerves such as the olfactory nerves and the optic nerves, but most contain both sensory and motor fibers.

They are protective membranes for the brain

1.) The outer meninx, a tough membrane, called the dura mater(tough mother).2.) The fine arachnoid membrane that is immediately inside of the dura mater. It is spiderweb-like. 3.) The innermost meninx, the delicate pia mater(pious mother), which adheres to the surface of the CNS.

This is the space beneath the arachnoid membrane, which contains many large blood vessels and cerebrospinal fluid.

Cerebrospinal fluid fills the subarachnoid space, the central canal of the spinal cord, and the cerebral ventricles of the brain. This fluid supports and cushions the brain. It is continuously produced by the choroid plexuses-networks of capillaries that protrude into the ventricles from the pis mater,

This barrier is a consequence of the special structure of cerebral blood vessels. It is a mechanism that impedes the passage of many toxic substances from the blood into the brain.

A lipid bilayer-two layers of fat molecules.

Multipolar Neuron-A neuron with more than two processes extending from its cell body. Most neurons are multipolar. Unipolar Neuron-a neuron with one process extending from its cell bodyBipolar Neuron-a neuron with two processes extending from its cell body Interneuron- neurons with short axons or no axons

CNS-nuclei. Tracts.PNS-Ganglia. Nerves.

They are glial cells with extensions that wrap around the axons of some neurons of the CNS. They provide several myelin segments, often on more than one axon