Transcript document

Alzheimer disease is caused by a decrease in the production of the
neurotransmitter acetylcholine in the brain. Cholinesterase inhibitors, such as the
drug donepezil, can slow the development of symptoms in the early-to-middle
stages of Alzheimer disease, but they cannot stop the progression of the disease.
The donepezil molecule has a shape that allows it to attach to the active site on
cholinesterase, thereby preventing the cholinesterase from binding to
acetylcholine
In the diagram above, acetylcholine and donepezil are
numbered
A. 1 and 2 respectively
B. 2 and 1 respectively
C. 3 and 4 respectively
D. 4 and 3 respectively
How does donepezil affect synaptic
transmission?
A. Donepezil breaks down acetylcholine so
that less acetylcholine is available in the
synapse.
B. Donepezil replaces cholinesterase so that
more acetylcholine is available in the
synapse.
C. Donepezil blocks the release of
acetylcholine so that less acetylcholine is
available in the synapse.
D. Donepezil prevents the breakdown of
acetylcholine so that more acetylcholine is
available in the synapse.
 Stimulation of a sensory neuron produces
an action potential. An abnormal pattern in
this action potential can be used to detect
MS in its early stages. The graph below
illustrates the membrane potential of a
normal neuron after stimulation.
 Which of the following types of ion movement
across an axon membrane would cause the
action potential to change during the interval
from 0.2 ms to 0.4 ms?
A. Sodium ions moving into the axon
B. Sodium ions moving out of the axon
C. Potassium ions moving into the axon
D. Potassium ions moving out of the axon
 On the graph, the period from 0.5 ms to 1.0 ms
represents the neuron’s
A. refractory period, which is when repolarization
occurs
B. refractory period, which is when minimum
depolarization occurs
C. threshold period, which is when repolarization
occurs
D. threshold period, which is when minimum
The Central
Nervous System
Chapter 13.3
Central Nervous
Composition
 The nervous system has distinct types of
tissues and fluids:
 White matter is any neuron with myelin.
 Grey matter is any neuron without myelin.
 Meninges are the tough membranes that
surround and protect the CNS.
 Cerebrospinal fluid acts as a shock absorber
and a transporter of nutrients and wastes.
Spinal Cord
 The spinal cord is composed of these tissues.
 White matter comprises the outer layers as
these are myelinated sensory and motor
neurons.
 Grey matter comprises the core as this is
unmyelinated interneurons.
 These interneurons are organized into a
channel that goes directly to the brain.
 Sensory neurons approach the spinal
cord in a bundle called the dorsal root.
 Motor neurons leave the spinal cord in a
bundle called the ventral root.
Structure of the Brain
 The largest part of the brain is the cerebrum.
 It stores and processes sensory information,
and initiates voluntary responses.
 It is separated into the left and right
hemisphere.
 The left hemisphere is associated with the right
side of the body and rational thought.
 The right hemisphere is associated with the left
side of the body and intuitive/creative thought.
 The two hemispheres can act independently,
but communication occurs between them
through the corpus callosum.


1.
2.
3.
4.
The cerebrum is covered in wrinkled
tissue known as the cerebral cortex.
This is divided into 4 regions, each with
associated functions:
Frontal Lobe
Temporal Lobe
Parietal Lobe
Occipital Lobe
Forebrain Structures

The forebrain also contains three other
structures:
1. Thalumus – Acts as a waystation for
incoming sensory information by
directing it to the associated cerebrum
lobe.
2. Hypothalumus – Works to control the
endocrine system.
3. Olfactory Lobes – Receive and interpret
smell sensations.
Hindbrain Structures

The hindbrain is comprised of 3
structures:
1. Cerebellum – Controls limb
movements, muscle tone and balance.
2. Medulla Oblongata – The control center
for the autonomic nervous system.
3. Pons – Acts as a bridge between the
cerebellum and medulla.
Comparing Brains
 We can compare brain composition of
various animals to determine certain
aspects.
Homework
 Pg 429 1-4
 Pg 430 Case Study
 Pg 432 1-6