146 MHR • Unit 2 Homeostasis
SECTION REVIEW- Identify the two major parts of the human
nervous system. - How is the autonomic system different from the
somatic system? - Which parts of your nervous system are you
using to complete this homework assignment? Make
a diagram of yourself and label the parts of your
nervous system that are working. - In Chapter 4 you learned that insulin and
glucagon are antagonistic hormones. Make a
diagram similar to Figure 4.15 on page 122 to show
that the sympathetic and parasympathetic nervous
systems are antagonistic systems. - What is a reflex arc? How is it useful to an
organism like you? - A sudden interruption in the blood supply to the
brain (known as a stroke) can cause serious brain
damage. Investigate how a stroke can affect a
person’s ability to speak naturally and clearly and to
comprehend what others are saying (in other words,
to communicate effectively). Present your findings in
a brief report to the class. - What factors contribute to the complexity of
the brain? - Explain how the EEG and PET scans help us to
understand brain function. - How have studies of people with brain disorders
helped us understand brain function? Explain your
answer. - Doctors sometimes conduct the “knee jerk” reflex
test during a physical examination. This test involves
quickly tapping a point just below the kneecap with a
rubber mallet. In a normal response, the lower part of
the leg jerks up and outward. What is the diagnostic
value of this type of test? Try this test in class under
the supervision of your teacher (use a ruler if mallets
are not available and be careful to tap gently). How
do individual responses to this test vary among your
classmates? Make a sketch of the reflex arc involved
in this type of test. In the sketch, include the sensory
receptor, sensory nerve, motor nerve, effector, spinal
cord, interneurons, and the brain (in outline). Use
arrows to indicate the direction of the nerve impulses. - Prions are proteins that can cause other proteins
to change shape and lose normal function. Bovine
spongiform encephalitis (BSE), also known as Mad
Cow Disease, is caused by prion infection. BSE
prions attack proteins in the brain, which eventually
leads to deterioration of brain tissue.
You are interested in conducting research about
prions.
(a)Identify some safety issues that need to be
addressed before you start.
(b)How could PET scans be helpful to monitor the
progress of this disease in an infected person?
(c)How could animal tests be useful?- Describe how damage to the CNS will have a
different impact than damage to the PNS. As medical
researchers study the effects of damage to both
types of nervous systems, consider the use of
implanting new stem cells or transplanting whole
neurons to reverse damage to nerve tissue. Which
strategy might be most effective for each system?
Explain your thinking. - Copy and complete the following chart.
- If possible, find out the age at which you and
your siblings took your first unassisted steps. Survey
your classmates about this question, and plot the
results on a graph. Use blue dots for boys and red
dots for girls. Does there seem to be a gender
difference with regard to the age at which infants
learn to walk? Should parents or other caregivers
encourage or prompt infant children to walk on
their own? - Discuss a situation in which you may have
experienced the symptoms of a fight-or-flight reflex.
How long did it take for your heart rate and breathing
rate to return to normal? Compare your fight-or-flight
experience with that of others in your class. Discuss
the apparent differences, if any, in the way males and
females experience the fight-or-flight reflex.
Wilder Penfield was able to do research on the human
brain because he had the “informed consent” of his
patients and proof that his experiments did no harm.
Gather some information on the ethics of both animal
and human experimentation.UNIT PROJECT PREP
CIBrain Structure Location Functions
Pons
Midbrain
Corpus callosum
Cerebellum
CerebrumCMCIIMCK/UK/UCK/UCCK/UK/U