Download 4/14

Your grade: in class and homework,
experiment, 3 X exams... Final
Plus up to 3 points for discussions

Exam 3 in-class Th 5/5
take-home will be due Th 4/28

Final exam is cumulative and optional
no take-home for the final exam

Nerves allow us to perceive the environment
while the brain integrates the incoming signals
to determine an appropriate response.
Fig 46.1
Response
Responses can be
release of hormones,
change in cell activity,
or muscle contraction
Muscles allow
movement
An earthworm: without something to push
against, muscles are not much use.
The skeleton, made
of bones, gives
support
Fig 50.34
Bones (connective tissue) are alive
Connections
between bones and
muscles
Muscles can only contract. Therefore, two
muscles are needed for each range of motion.
Fig 50.32
2 nerve signals for
every movement:
excitatory and
inhibitory
Fig 50.32
How do
muscles
contract?
Excitatory
neurotransmitters
released by
motor
neurons
cause
muscle cells
to contract
Fig 50.29
Muscle cells are
comprised of
series of
sarcomeres.
Fig 50.25
Fig 50.25
Each
sarcomere
is a
repeating
unit of
actin and
myosin
proteins
Fig 50.25
As each
sarcomere
contracts,
the muscle
cell
contracts
Fig 50.27
ATP
provides
the energy
for myosin
movement
along the
actin
Fig 50.25
How is this
regulated?
Neurotransmitters
released at
nerve/
muscle
junction cause
calcium to be
released in
muscle
Fig 50.29
Fig 50.28
A third
protein,
tropomyosin
controls
when the
muscle
contracts
The
contraction
of muscle
cells
causes the
muscle to
contract
muscle contraction animation:
http://www.blackwellpublishing.com/matthews/myosin.html
Cadavers and muscles
http://www.youtube.com/watch?v=xdZR4znKRV0
In class 4/14:
What is consciousness?
Who has it?
People? Non-human animals? Plants?
Computers?
How can you measure consciousness?
Is consciousness important?
Your grade: in class and homework,
experiment, 3 X exams... Final
Plus up to 3 points for discussions
