Exam #3 W 4/2 in classReview T 4/1 from 5-7pm in PAI 3.02Before Exam #3: the nervous system, movement and the immune system
CB 48.3
Nerves allow us to perceive the environment while the brain integrates the incoming signals to determine an appropriate response.
Response
CB 48.5Neurons: signals move through neurons electrically and between neurons chemically
electrical electricalat synapse chemical
At the synapse the electrical signal is converted to a chemical signal
CB 48.16
Neurons are commonly connected to many other neurons, and the effect of the different incoming signals determines what the neuron will do.
Incoming signals move through neurons. Only signals above the threshold are transmitted along the neuron.
CB 49.3
Sensory neurons in human skin
Nervous System Signaling
Stimulus
Transduction Transmission
Response
Integration
Smells are detected by receptor neurons in our nose. Each receptor is sensitive to a different chemical
CB 49.15
CB 48.19
The brain and the central nervous system integrate the various incoming signals
CB 48.23
Human Brain Development:Cerebrum- integration and memoryBrainstem- homeostasis and input sensory infoCerebellum- motor functionsDiencephalon- input to cerebrum and homeostasis
CB 48.26
Cerebrum: higher brain function
CB 48.26Neocortex: thin layer on outside of the cerebrum. Highly convoluted in humans, ~5mm thick but ~80% brain mass.
CB 48.26
Corpus Callosum: communication between hemispheres
CB 48.27Different regions of the cerebral cortex integrate different inputs/outputs
CB 48.29Visualizing the specialization of brain regions
CB 48.28
Some body parts have more sensory input/motor control
Sensory inputmotor output
CB 48.3
Nerves allow us to perceive the environment while the brain integrates the incoming signals to determine an appropriate response.
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.
CB 49.25
The skeleton, made of bones, gives support
CB 49.26
Bones (connective tissue) are alive
Connections between bones and muscles
CB 49.27
Muscles can only contract. Therefore, two muscles are needed for each range of motion.
2 nerve signals for every movement:excitatory and inhibitory
CB 49.27
How do muscles contract?
CB 49.32Excitatory neuro-transmitters released by motor neurons cause muscle cells to contract
Muscle cells are comprised of series of sarcomeres.
CB 49.28
Each sarcomere is a repeating unit of actin and myosin proteins
CB 49.28
As each sarcomere contracts, the muscle contracts
CB 49.28
CB 49.32Neuro-transmitters released at nerve/muscle junction cause calcium to be released in muscle
CB 49.31
A third protein, tropomyosin controls when the muscle contracts
CB 49.30
ATP provides the energy for myosin movement along the actin
CB 49.32 and .33
The contraction of muscle cells causes the muscle to contract
CB 48.3
Nerves allow us to perceive the environment while the brain integrates the incoming signals to determine an appropriate response.
Response
Responses can be release of hormones, change in cell activity, or muscle contraction
How do muscles contract?
http://health.howstuffworks.com/adam-200006.htm
Einstein’s Brain:http://youtube.com/watch?v=JNOKT-xv7Dw
A video about different human reactions to cool:http://www.pbs.org/saf/1507/video/watchonline.htm
Exam #3 W 4/2 in classReview T 4/1 from 5-7pm in PAI 3.02Before Exam #3: the nervous system, movement and the immune system