Comparison of Herbivore, Carnivore and Nectar Feeder
Syllabus Dot Point
· Identify data sources, gather, process, analyse and present information from secondary sources and use available evidence to compare the digestive systems of mammals, including a grazing herbivore, carnivore and a predominantly nectar feeding animal
/ Mammalian Carnivore / Mammalian Herbivore / Mammalian Nectar Feeder /Examples of animals in this group / Humans, pigs, etc. / Cattle, sheep, etc. / The honey possum is a small, mouse-sized
marsupial mammal that lives in south-western
Australia.
Chemicals common in foods ingested by animal / Our system is designed to digest and absorb protein and fats – substances that do not require long time processes to break down the nutrients
· Protein as amino acids
· Fats/Lipids as fatty acids & glycerol
· Carbohydrates as simple sugars (monsaccharides) / Ruminant animal
· High carbohydrate diet with lower amounts of protein – the protein is less concentrated than in the flesh of an animal
· Farmers and protein supplements – problems “mad cow disease” / The dietary specialisation of honey possums appears not to be due to any specialisation of the digestive system but to the specialisations of the tongue and palate which enable the animal to harvest sufficient pollen and nectar to provide protein and energy required for all life’s purposes.
Diagram of digestive system (cut & paste from internet) / / /
Comparison of system parts – teeth / Teeth include:
· Canines (small) – grabbing/ripping
· Incisors - cutting
· Molars - grinding / Teeth include:
· Nipping/cutting teeth
· Molars - grinding / The incisors and canines are pointed but the cheek teeth are flattened pegs with rounded tips and do not resemble the normal structure of mammalian teeth
Comparison of system parts – stomach(s) / Monogastric – 1 stomach
Contains acid (HCl) digestion of protein requires acidic conditions / Ruminant – more than 1 stomach – actually 4 Rumen, Omasum, Abomasum and reticulum
Rumen (main large stomach) has bacteria and other organisms that breakdown cellulose and complex carbohydrates into simple sugars - fermentation / It has a large, two-chambered stomach.
Comparison of system parts – small intestine / Most nutrient absorbed here
The surface area for absorption is maximised by villi
Amino acids + simple sugars into blood
Fatty acids into the lymph / Most nutrient absorbed here
The surface area for absorption is maximised by villi
Amino acids + simple sugars into blood
Fatty acids into the lymph / Pollen (high in protein and carbohydrate) is digested progressively in the small intestine.
Comparison of system parts – Caecum / Contains bacteria to assist in breakdown of foods – extremely small and of little usage / Contains bacteria to assist in breakdown of foods – larger than in monogastric animal / First it lacks a caecum so there is little to help us identify where the small intestine finishes and where the large intestine starts!
Comparison of system parts – Large Intestine / Much shorter (length) than small intestine
Absorption of
· Water
· Vitamins
· minerals / Much shorter (length) than small intestine
Absorption of
· Water
· Vitamins
· minerals