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Description
In this programme an enquiry into the structure and function of an 'unknown' organ is staged as an illustration of how such a problem might be investigated by a scientist. The speakers are Mr. Step...hen Hurry, Senior Lecturer in Biology at the Open University, Dr. Richard Holmes, Lecturer in Biology at the Open University, and Dr. Margaret (Peggy) Varley, Senior Lecturer in Biology at the Open University. The organ featured in this enquiry is the salt gland of the domestic goose. Evidence is presented from study of anatomy, histology, physiology, natural history and references in the biological literature. From these lines of evidence a picture is built up of the part played by the organ in the life of its possessor.
In this programme an enquiry into the structure and function of an 'unknown' organ is staged as an illustration of how such a problem might be investigated by a scientist. The speakers are Mr. Step...hen Hurry, Senior Lecturer in Biology at the Open University, Dr. Richard Holmes, Lecturer in Biology at the Open University, and Dr. Margaret (Peggy) Varley, Senior Lecturer in Biology at the Open University. The organ featured in this enquiry is the salt gland of the domestic goose. Evidence is presented from study of anatomy, histology, physiology, natural history and references in the biological literature. From these lines of evidence a picture is built up of the part played by the organ in the life of its possessor.
| Module code and title: | S22_, Comparative physiology |
|---|---|
| Item code: | S22_; 10; 1972 |
| Series: | Comparative physiology |
| Episode | 10 |
| First transmission date: | 03-06-1972 |
| Published: | 1972 |
| Rights Statement: | Rights owned or controlled by The Open University |
| Restrictions on use: | This material can be used in accordance with The Open University conditions of use. A link to the conditions can be found at the bottom of all OUDA web pages. |
| Duration: | 00:22:51 |
| + Show more... | |
| Producer: | Tony Laryea |
| Contributors: | Richard Holmes; Stephen Hurry; Peggy Varley |
| Publisher: | BBC Open University |
| Keyword(s): | Anatomy; Biological literature; Goose; Histology; Illustration; Natural history; Physiology; Salt gland |
| Footage description: | Peggy Varley introduces the programme. In it is staged an enquiry into the structure and function of an unknown organ as an illustration of the types of evidence that could be gained from a study of anatomy, histology, physiology, natural history and reference to biological literature. She dissects back the skin on the head of a domestic goose and exposes a gland, the subject of the investigati which is located directly above the eyeball. Varley then introduces Stephen Hurry. Stephen Hurry examines the gross anatomy of the gland. He uses a diagram to show what would be found if a dissection had actually been carried out. He shows that the gland has a richblood supply, a duct leading to the nostril and a parasympathetic motor nerve supply. Hurry then shows a series of micro-graphs of sections of the gland. His commentary describes the tissue features. He then sums up the information gained from his histological investigation - that the gland is a secretory structure passing material from the blood out of the body (an exocrine gland). Peggy Varley uses the biological literature to gain clues for determining what material is actually excreted by the gland. She quotes from several articles. These suggest that the salt level in the water intake of the birds cause a waxing and waning in the size of thegland. Shots of domestic goose which has been given a large dose of sea water. A secretion can be seen coming from its nostrils. Peggy Varley explains that the secretions from its nostrils. The secretion contains a high percentage of salt (NaCl) then introduces Richard Holmes. Richard Holmes discusses the mechanism by which the gland removes salt from the blood. He explains how this can be determined experimentally. Holmes uses several animated graphs to aid his discussion. Holmes then examines the gland activating mechanism. He again uses diagrams to aid and concludes that the gland is controlled by its motor nerves whose receptors are located in the pericardium or the heart. Holmes explains the experimental techniques used to isolate the activating mechanism. Shots of a domestic goose strapped down over a funnel. The goose is subjected to prolonged salt loading and the urine and faeces are collect for salt content analysis. The nostril ducts are also emptied for analysis. It is found that up to 90% of the salt load is removed by the salt gland with the rest being removed by the kidneys. Peggy Varley discusses the presence of salt glands in other sea birds and sea reptiles. Shots of a pelican, petrel, sea turtle and sea iguana. |
| Master spool number: | 6LT/70545 |
| Production number: | 00521_3102 |
| Videofinder number: | 3584 |
| Available to public: | no |
