The digestive system
Lamprey and hagfish are parasitic but belongs to cyclostomata. The larger its internal surface, the greater its absorptive efficiency , and a spiral valve is one method of increasing its absorption surface. Request an e-inspection copy. The digestive tube also contains numerous intramural glands which provide the tube by lubricating mucus, enzymes, water, etc. Bile is excreted from the bladder to the intestine via the bile duct.
A. Digestive System
The student resources previously accessed via GarlandScience. What are VitalSource eBooks? For Instructors Request Inspection Copy. Preface List of Contributors 1. Feeding Activity in Teleost Fish: Azevedo Index Color Plate Section. We provide complimentary e-inspection copies of primary textbooks to instructors considering our books for course adoption. Learn More about VitalSource Bookshelf. CPD consists of any educational activity which helps to maintain and develop knowledge, problem-solving, and technical skills with the aim to provide better health care through higher standards.
It could be through conference attendance, group discussion or directed reading to name just a few examples. Caecae are present in salmonids but absent from cyprinid species. An important source of digestive enzymes is the pancreas. This organ is adjacent to the stomach and can be a discrete or diffuse organ depending on species.
In salmonids the pancreas is a diffuse collection of cells interwoven amongst the pyloric caecae. Enzymes are produced by the pancreas only in the presence of food and are involved in the breakdown of all nutrients. Both the liver and the gall bladder play an important role in digestion.
The liver both assimilates the products of digestion into usable forms and aids the digestive process through the production of bile which is stored in the gall bladder. The size and fullness of the gall bladder is indicative of feeding status in fish. A large, distended bladder indicates that the fish has not eaten for some time whilst an empty flaccid bladder indicates that the fish has recently eaten a meal.
Bile is excreted from the bladder to the intestine via the bile duct. Emulsification helps to maintain a large surface area from attack by lipases which break fat down through a process known as Catabolism to glycerol,fatty acids and glycerides. The basic format is:. Fish have some unique anatomical and physical characteristics that are different from mammals; however, they still possess the same organ systems that are present in other animals.
All fish are poikilothermic and must be able to adapt to changes in water temperature. Fish live in a variety of temperatures ranging from less than 0 C to hot geothermal springs. Yet, each species of fish must live in its particular specific temperature range. Culture and religion anatomy and physiology bioluminescence In bioluminescence: The role of bioluminescence in behaviour body part regeneration In regeneration: Fishes chemoreception In chemoreception: Fish circulatory system In circulatory system: Circulation in jawed vertebrates excretory system In excretion: Fishes hearing ability In sound reception: Hearing in fishes View More.
Animal Corner - Fish ThoughtCo. Articles from Britannica Encyclopedias for elementary and high school students. Help us improve this article! Contact our editors with your feedback. Introduction General features Structural diversity Distribution and abundance Natural history Life history Behaviour Locomotion Reproduction Form and function Body plan The skin The muscle system The digestive system The respiratory system The circulatory system Excretory organs Endocrine glands The nervous system and sensory organs Olfaction Taste Sight Hearing Other senses touch, pain, and special senses Evolution and paleontology Agnatha: You may find it helpful to search within the site to see how similar or related subjects are covered.
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