Cells of the Nervous System ch. 2.1

• rough for translation; smooth for transport/modification of new proteins;
• network of tubes that modify & transport newly made proteins within the cell

• no ribosomes

• associated with ribosomes; involved in translation

• puts finishing touches on newly made proteins

• energy production; performs metabolic activities to make energy for the cell

• clean-up; breakdown of waste products

• semipermeable lipid bilayer; separates the inside of the cell from the outside environment

It is a semipermeable lipid bilayer. It is composed of two layers of fat molecules that are free to flow around one another. Most chemicals cannot cross the membrane, but specific protein channels in the membrane permit a controlled flow of water, oxygen, sodium, potassium, calcium, chloride, and other important chemicals.

- 2 layers of fat molecules that are free to float around one another

- Water, oxygen, & carbon dioxide move freely

Na+, Ca2+, K+, Cl- move thru ion channels (protein channels)

Most chemicals cannot cross cell membrane

- branching fibers that get narrower near their ends; receive information

- the short outgrowths that increase the surface area available for synapses; receive specialized incoming information (that info apparently plays a key role in long-term changes in the neuron that mediate learning and memory)

- contains the nucleus, ribosomes, mitochondria, and other structures found in most cells; much of the metabolic work of the neuron occurs here

- a thin fiber of constant diameter; it is the information sender of the neuron, conveying an impulse toward other neurons or an organ or muscle

- many vertebrate axons are covered with this insulating material; it helps the information move faster

- interruptions between myelin sheath

- sends out information; here the axon releases chemicals that cross through the junction between one neuron to the next

- The cell body (soma) lives in the spinal cord. The axon is part of a nerve in your body. The terminals are in your muscles; Efferent from the nervous system; MULTIPOLAR

- The soma lives just outside of the spinal cord (in a dorsal root ganglion). Most of its length is an axon. It has specialized endings in the skin, and its terminals are in the spinal cord; Afferent to the nervous system; UNIPOLAR

- wrap around terminals of related axons, remove waste material, and dilate blood vessels in active regions of brain, BBB

- repair (remove waste, fungi, microorganisms); “first responders”

: guide cell and axon migration during development; after development turn into neurons

- puts myelin on axons in the CNS

: myelinates axons of the PNS

- where 2 cells “meet”

- type of cell that sends information

- the minute gap between presynaptic cell and postsynaptic cell in a chemical synapse, across which the neurotransmitters diffuse into

- leading toward an organ or part

Ex. An _______ axon brings information into a structure  sensory neurons are all ____ to the rest of the nervous system

- conducting away from an organ or part

Ex. An ________ axon carries neurons away from a structure  motor neurons are all _____ from the nervous system

- a thin layer of endothelial cells w/ tight junctions surrounding capillaries that lines the interior surface of blood vessels; astrocytes surround the endothelial cells

- viruses and bacteria, chemicals, nutrients

- small uncharged molecules, fat-soluble molecules (vitamin A and D, psychotropic drugs), glucose (special transport)

- it can also block out nutrients that are useful to the brain and potentially helpful chemicals; sometimes if a virus does enter it can slow reproduction but never fully eliminate the virus (chickenpox, shingles, genital herpes)