Available online
Description
Use of laser and x-ray diffraction techniques in the study of filament organisation of muscles are examined.
Use of laser and x-ray diffraction techniques in the study of filament organisation of muscles are examined.
| Module code and title: | S321, Physiology of cells and organisms |
|---|---|
| Item code: | S321; 06 |
| First transmission date: | 28-04-1974 |
| Published: | 1974 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:22:39 |
| + Show more... | |
| Producer: | John Groom |
| Contributors: | Gerald Elliott; David Gayton |
| Publisher: | BBC Open University |
| Keyword(s): | ADP heads; Muscle filaments; Sliding filament hypothesis; X-ray diffraction |
| Footage description: | Gerald Elliott introduces the programme with a brief discussion of Hugh Huxley's work on muscle tissue. Shot of Huxley, an electron microscope, and on an EM micrograph of muscle tissue. Elliott explains the disadvantages of using electron microscopy for tissue study. He then discusses the advantages and disadvantages of light microscopy for tissue study. Shot of laser diffraction pattern. Elliott explains how the pattern arises. He uses a diagram to aid. Elliott places a muscle fibre into the apparatus and passes a laser beam through it. The diffraction pattern is shown on the screen. David Gayton with a giant Pacific barnacle. He explains why muscle tissue from this animal is used for x-ray and laser diffraction experiments. Gayton dissects out a muscle fibre and prepares it for diffraction experiments. Shot of a laser diffraction pattern for a barnacle fibre. Gayton explains the meaning of the pattern. Gayton places the fibre specimen in an x-ray diffraction apparatus. He explains how the x-ray diffraction process works. Commentary by Elliott interprets the pattern. Several diagrams are used as aids. Gayton discusses Huxley's discovery that shortening and lengthening a muscle fibre does not change its unit volume, (Animated diaqrams aid.) Gayton introduces; C. Elliott who discusses an x-ray diffraction experiment he developed to test Huxley's work on contracting muscles. Elliott gives details of his experiment. Animated diagrams aid. He found that the constant volume effect applied to a contracting muscle as well as muscle at rest. Elliott uses Several x-ray diffraction patterns and diagrams to explain the sliding filament hypothesis. David Gayton discusses re-arrangement of matter in muscle fibres by means other than change of sarcomere length. He uses x-ray diffraction pictures to aid. In this technique the diffraction patterns are used to produce electron density maps. Shot of an electron density map. Elliott sums up the two effects which produce changes in intensity of spots at the equator of the muscle x-ray diffraction pattern. Diagrams aid his commentary. Gayton sums up Elizabeth Rome's experiments which showed the relationship between pH and interfilament distance. Shots of graphs and diagrams aid. Elliott sums up another aspect of E. Rome's work. Here the ionic strength of the ninth filament medium was changed. Filament length changed dramatically. Graph and diagram aids. Gayton briefly discusses the attractive forces between filaments of muscle fibre. He then introduces Elliott who will explain why the myacin head moves across from myacin filament to the active filament. G. Elliott uses an animated diagram to explain movement of the myacin head from myacin filament to action filament during contraction. |
| Master spool number: | 6HT/71222 |
| Production number: | 00525_1110 |
| Videofinder number: | 1823 |
| Available to public: | no |
