20 October 2010 This Week in Physiology: Lab: Sensory Physiology & Visual System Lectures: Ch. 9...

20 October 2010This 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

Approaching Fall Break!

Special PresentationHosted 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 MorrisonDirector 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).

Stimulus

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?

Four first-order sensory neurons with receptive membranes at bottom.

1QQ # 20 for 8:30 am

Stimulus

1QQ # 20 for 9:30 am

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.

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?

A B C D

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!

S 1

S 2

Fig. 09.14

Synonyms:NMJ = neuromuscular junctionMyoneural junctionMotor end plate

S 3

Fig. 09.151 AP in motor axon releases sufficient ACh for 1 AP in skeletal muscle.

Nicotinic

Myasthenia gravis and loss of nAChRs

EPP

S 4

Fig. 09.01a

Capillaries

How does AP in sarcolemma cause twitch?

Oxygen, Nutrients,hormones,waste

S 5

Fig. 09.11b

Terms: Myofiber, myofibril, myofilament

Thick myofilament = myosinThin myofilament = actin

S 6

Fig. 09.11a

S 7

Fig. 09.12

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…

High fAP leads to accumulation of Ca++ in sarcoplasm because Ca++ ATPase doesn’t return all Ca++ to SR quickly enough.

S 8