Chapter 3 Part 1

Question 1

Neurons:

Answer 1

Specialized cells that are the basic building blocks of the nervous system.

Question 2

Dendrites:

Answer 2

They emerge from the cell body in branchlike fibres and are the receiving unites that collect messages and send them on to the cell body

Question 3

Axon:

Answer 3

An extension from one side of the neuron cell body that conducts nerve impulses to other neurons, muscles, or glands.

Question 4

Glial Cells:

Answer 4

Surround neurons and hold them in places, manufacture nutrient chemicals that neurons need, form the myelin sheath around axons, and absorb toxins and waste materials that might damage neurons.

Question 5

Blood-brain barrier:

Answer 5

Prevents many substances, including a wide range of toxins, from entering the brain. The walls of the blood vessels within the brains contain smaller gaps and are covered by specialized glial cells.

Question 6

Resting potential:

Answer 6

The electrical activity of neurons, the internal diffence of the sodium ions outside of a cell and the negatively charged protein ions inside the cell

Question 7

Action potential:

Answer 7

A nerve impulse resulting from the depolarization of an axon’s cell membrane

Question 8

Depolarization:

Answer 8

The shift from negative to positive voltage

Question 9

All or none law:

Answer 9

The fact that an action potential is not proportional to the intensity of stimulation. A neuron either fires with max intensity or it does not fire at all.

Question 10

Myelin Sheath:

Answer 10

A fatty, whitish insulation layer around axons and interrupted at regular intervals by the node of Ranvier.

Question 11

Synapse:

Answer 11

the microscopic space between neurons over which the nerve impulse is biochemically transmitted

Question 12

Neurotransmitters:

Answer 12

Chemical substances that carry messages cross the synapse to either excite other neurons or inhibit their firing

Question 13

Multiple sclerosis:

Answer 13

neurological disorder characterized by demyelination of axons because immune system attacks myelin sheath

Question 14

Five Step process of chemical communication between neurons

Answer 14

1. Synthesis: chemical molc. are formed inside neuron
2. Storage: Molc. stored in chambers called synaptic vesicales within axon terminal.
3. Release: Molc. released into space between axon and membrane of receiving neuron
4. Binding: Molc. cros synaptic space and attach to receptor sites
5. Deactiviation.

Question 15

Excitatory Neurotransmitter:

Answer 15

Depolarizes neurons’s membrane which increases likelihood of action potential.

Question 16

Inhibitory neurotransmitter:

Answer 16

Hyper polarizes neuron’s membrane which decreases likelihood of action potential.

Question 17

Glutmatic acid:

Answer 17

Excitatory neurotransmitter, involved in control of all behaviours, especially important in learning and memory

Question 18

GABA (Gammaaminobutyric acid):

Answer 18

Inhibitory transmitter, important in anxiety and motor control. Destruction in Huntington’s disease produces tremors and loos of motor control, as well as personality changes.

Question 19

Acetylcholine:

Answer 19

Excitatory at synapses involved in muscular movement and memory. Memory loss in Alzheimer’s disease (undersupply) or muscle contractions (oversupply)

Question 20

Norepinephrine:

Answer 20

Involved in neural circuits controlling learning, memory, wakefulness, and eating. Depression (undersupply) or stress and panic disorders (oversupply)

Question 21

Serotonin:

Answer 21

Involved in mood, sleep, eating, and arousal, may be important in pain and pleasure. Depression, sleeping, and eating disorders (undersupply)

Question 22

Dopamine:

Answer 22

Involved in voluntary movement, emotional arousal, leaning, motivation, experiencing pleasure. Parkinson’s disease and depression (undersupply) Schizophrenia (oversupply)

Question 23

Endorphins:

Answer 23

Inhibits transmission of pain impulses. Insensitivity to pain (oversupply) Pain hypersensitivity, immune problems (oversupply)

Question 24

Three major types of neuron

Answer 24

1. Sensory neurons: carry input messages from sense organs to the spinal cord and brain
2. Motor neurons: transmit out impulses from the brain and spinal cord to the body’s muscles and organs
3. Interneurons: Perform connective functions within the nervous system

Question 25

Central nervous system:

Answer 25

consisting of all neurons in the brain and spinal cord

Question 26

Peripheral nervous system

Answer 26

Composed of all the neurons that connect the central nervous system with the muscles, glands, and sensory receptors

Question 27

Somatic nervous system: (Part of peripheral nervous system)

Answer 27

transmit messages from the eyes,ear, and other sensory receptors as well as motor neurons that send messages from brain and spinal cord to muscles.

Question 28

Autonomic nervous system: (Part of peripheral nervous system)

Answer 28

controls glands and the smooth (involuntary) muscles of the hearts, blood vessels, and stomach + intestines

Question 29

Sympathetic nervous system: (type of autonomic nervous system)

Answer 29

Speeds up bodily processes and mobilizing the body using an arousal function on the body’s internal organs.

Question 30

Parasympathetic nervous system: (type of autonomic nervous system)

Answer 30

Slows down body processes and maintains or returns you to a state or rest.

Question 31

Homeostasis:

Answer 31

The maintenance of biological equilibrium within the body

Question 32

Spinal Cord

Answer 32

• most nerves enter/leave through spinal cord
• spinal reflexes do not involved brain
• central portion consists of grey, unmyelinated neurons
• outer portion consists of white myelinated neurons

Question 33

Neuropsychological tests

Answer 33

tests used in clinical evaluations of people who may have suffered brain damage

Question 34

Destruction and Stimulation Techniques

Answer 34

removing portions of the brain or stimulating specific areas using a mild electric current. These methods are useful when learning about the brain

Question 35

Electroencephalogram (EEG)

Answer 35

Device used to record the simultaneous activity of many thousands of neurons through electrodes attached to the scalp. Some patterns correspond to wakefulness and sleep

Question 36

CT scans - Computerized axial tomography

Answer 36

Uses X-ray technology to take pictures of narrow slices of brain, a computer then reconstructs the interior from many different angles

Question 37

Positron emmission tomography (PET)

Answer 37

Measures brain activity, blood flow, metabolism, neurotransmitter activity. Gluscose, being a major nutrient in neurons, is injected as radioactive glucose. The energy emitted is measured by PET scan to shows active parts of the brain

Question 38

Magnetic Resonance Imaging (MRI)

Answer 38

Combines CT and PET scans by creating images based on how atoms in living tissue respond to its magnetic pulse.

Question 39

functional MRI

Answer 39

Produces pictures of blood flow in the brain less than a second apart enabling live feed of brain activity