Available online
Description
This programme deals with some of the research that has been done on the Weddell Seals and similar animals by physiologists. The programme is introduced by Dr. Richard Holmes of the Open University... but most of the narration is by Squadron Leader David Denison of the Institute of Aviation Medicine, Farnborough, who has himself been engaged on such research projects in the Antarctic.
This programme deals with some of the research that has been done on the Weddell Seals and similar animals by physiologists. The programme is introduced by Dr. Richard Holmes of the Open University... but most of the narration is by Squadron Leader David Denison of the Institute of Aviation Medicine, Farnborough, who has himself been engaged on such research projects in the Antarctic.
| Module code and title: | S321, Physiology of cells and organisms |
|---|---|
| Item code: | S321; 13 |
| First transmission date: | 18-08-1974 |
| Published: | 1974 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:03 |
| + Show more... | |
| Producer: | John Groom |
| Contributors: | David Denison; Richard Holmes |
| Publisher: | BBC Open University |
| Keyword(s): | Decompression sickness; Depth diving; Insulation; Nitrogen narcosis; Weddell seals |
| Footage description: | The programme examines the physiological mechanisms which enable the Weddell seals to resist heat loss and dive deeply without harmful effects. Shots of a deep sea diver being lowered into the water. Shots of the diver on the sea floor. Commentary by Richard Holmes explains some of the physiological problems he encounters. Shots of the diver simulating some of the symptoms of nitrogen narcosis. Shots of micrographs showing nitrogen bubbles in the bloodstream. Richard Holmes discusses the problem of cold as encounterd by divers. He uses a graph showing water temperature at various depths to illustrate his point. Shots of skin divers going through a hole in the ice in antarctic waters. Shots of the divers under the ice. Shots of a seal swimming under the ice. Holmes contrasts the seals ability to function in the cold and at depth with that of man. He then introduces David Denison. Denison examines the methods used by seals to protect themselves from the cold. Shots of deer and seals. He then discusses the breeding behaviour of the Weddell seal. Various shots of adult and pup seals. Denison examines the way in which pups manage to survive without a protective layer of blubber but with a good fur coat. Denison describes the experiments which were done on pups to monitor their core body temperature. A graph shows the variation during the first few hours after birth. Denison discusses a further experiment which was performed to determine the relative roles of insulation and heat production in maintaining the core body temperature of the seal pups. Shots of graphs showing the results. Denison describes experiments which were done to determine the ability of seal pups to cope with the added heat loss of first exposure to water. Graphs, show the results of the experiments. Holmes sums up the thermal retention properties of seal pups. Holmes begins a discussion on decompression problems following deep dives. He discusses experiments in this area done with Weddell seals. Shots of the experiment in progress. Graphs show the diving ability and habits of the seals. Holmes and Denison examine the reasons for immunity to decompression sickness in seals. Micrographs compare seal lung tissue with tissue from lungs of land mammals. Denison demonstrates the effect of this difference using two model lungs. He then continues his discussion on experiments which helped to determine the reasons for the deep diving ability of seals. Graphs show some of the results. Denison sums up. Holmes sums up. |
| Master spool number: | 6HT/71505 |
| Production number: | 00525_1117 |
| Videofinder number: | 1831 |
| Available to public: | no |
