Neurons and Glia

Question 1

neuron

Answer 1

— (nerve cell)
— information-processing cell of the nervous system
— most use action potentials to send signals over a distance
— all neurons communicate with one another using synaptic transmission
— sense changes in the environment, communicate these changes to other neurons, and command the body’s responses to these sensations
— range of 0.01 to 0.05 mm in diameter
— Greek: νεῦρον (sinew, cord, nerve)

Question 2

glial cell

Answer 2

— insulate, support, and nourish neighboring neurons
— four categories: astrocytes, oligodendroglial, Schwann cell, and microglia
— Greek: γλία (glue)

Question 3

microtome

Answer 3

— any of various instruments used to cut thin sections for microscopy

Question 4

histology

Answer 4

— a branch of biology or pathology dealing with the microscopic study of the structure of tissues

Question 5

Nissl stain

Answer 5

— after Franz Nissl (1860-1919)
— class of basic dyes that stain somata of neurons
— enables histologists to study arrangements of neurons in different parts of the brain

Question 6

cytoarchitecture

Answer 6

— arrangement of neuronal cell bodies in various parts of the brain

Question 7

Golgi stain

Answer 7

— after Camillo Golgi (1843-1926)

— silver chromate solution that stains brain tissue, showing neurons with all of their neurites

Question 8

soma

Answer 8

— cell body aka perikaryon
— central region containing nucleus
— about 20 µm

Question 9

neurite

Answer 9

— thin tube extending from a neuronal cell body

Question 10

axon

Answer 10

— neurite specialized to conduct nerve impulses, or action potentials, typically away from the soma

Question 11

dendrite

Answer 11

— neurite specialized to receive synaptic inputs from other neurons

Question 12

cell theory

Answer 12

— states that the individual cell is the elementary functional unit of all animal tissues

Question 13

neuron doctrine

Answer 13

— the cell theory applies to the nervous system

— neurons communicate by contact as opposed to continuity

Question 14

cytosol

Answer 14

— watery, salty, and K-rich fluid in the cell, kept inside by the neuronal membrane

Question 15

organelles

Answer 15

— membrane-enclosed structures inside a cell

— most importantly: nucleus, rough ER, smooth ER, Golgi apparatus, mitochondria

Question 16

cytoplasm

Answer 16

— everything containe within the confines of the cell membrane, excluding the nucleus

Question 17

nucleus

Answer 17

— Latin: (nut)