20 October 2010
Approaching Fall Break!
This Week in Physiology:
Lab: Sensory Physiology &
Visual System
Lectures: Ch. 9 Muscle
Physiology
Next Week in Physiology:
Lab: Frog muscle physiology
Lectures: Ch. 9 Muscle
Physiology
Special Presentation
Hosted by
Alpha Epsilon Delta
The Pre-Health Professions Society
Wednesday, October 20th
6:00 pm, Milliken 122 (The Pit)
a joint presentation by
Wofford alumnus and professor Dr. Noel Brownlee and
Director of Admissions at VCOM Mattie Bendall.
Brownlee & Bendall will discuss the training and
practices of osteopathic and allopathic physicians.
Special Presentation
Dr. Barbara Morrison
Director of the Medical Technology Program
Palmetto Health Richland
Describes the Medical Scientist Laboratory program
and career opportunities in medical technology
11:00 a.m.,
Thursday, Oct.21, in
RMSC 122 (The Pit).
1QQ # 20 for 8:30 am
Four first-order sensory neurons with
receptive membranes at bottom.
1. If the stimulus is applied at the
black bar, which sensory neuron
will have the highest frequency of
action potentials and why?
2. If the stimulus is applied at the
black bar, which sensory neuron
will have the lowest frequency of
action potentials and why?
3. What happens at the region of
the membrane indicated by the
arrow?
Stimulus
Consider the four second-order sensory
neurons (A- D) across the top of the
diagram.
Assume there are interneurons
arranged in a typical pattern that
interconnects these neurons.
1QQ # 20 for
9:30 am
A
B
C
D
1. If the stimulus is applied at the
black bar, which 2nd order neuron
will have the highest frequency of
action potentials and why?
2. If the stimulus is applied at the
black bar, which 2nd order neuron
will have the lowest frequency of
action potentials and why?
Stimulus
S1
Characteristics: Location, cell shape, nuclei per cell, innervation,
connections to adjacent myofibers, arrangement of actin and myosin,
regulation of cross bridges, sources of Ca++, response to injury, etc.
Different types of muscles for different tasks!
S2
S3
Synonyms:
NMJ = neuromuscular junction
Fig. 09.14
Myoneural junction
Motor end plate
S4
1Fig.AP
in motor axon releases sufficient
09.15
ACh for 1 AP in skeletal muscle.
Nicotinic
EPP
Myasthenia gravis and loss of nAChRs
S5
Fig. 09.01a
Capillaries
Oxygen,
Nutrients,
hormones,
waste
How does AP
in sarcolemma
cause twitch?
S6
Terms: Myofiber, myofibril, myofilament
Fig. 09.11b
Thick myofilament = myosin
Thin myofilament = actin
S7
Fig. 09.11a
S8
Fig. 09.12
High fAP leads
to accumulation
of Ca++ in
sarcoplasm
because Ca++
ATPase doesn’t
return all Ca++
to SR quickly
enough.
The concentration of free calcium is directly related to force
of contraction in skeletal muscle
Thus we need to understand the cellular mechanism of
contraction… cell biology flashbacks…