Common Requirements of living things - ANIMALS – Chapter 5

1. Common Requirements of living things - ANIMALS – Chapter 5

2. Autotrophic Unicellular Organisms Light energy Heat energy Organic compounds Water + dissolved Inorganic nutrients Carbon dioxide + Oxygen Carbon dioxide + Oxygen Wastes Diffusion & osmosis in / out of the cell - Active & Passive

3. Heterotrophic Unicellular Organisms Organic matter ‘food’ Heat energy Water + dissolved Inorganic nutrients Water + dissolved Inorganic nutrients Oxygen Carbon dioxide Diffusion & Osmosis in and out of the cell - Active and passive Phagocytosis or endocytosis of organic matter Organic wastes

4. No Digestion Required • Very few multicellular animals absorb nutrients directly from the environment. • Exceptions include parasites that absorb nutrients that have been digested by the host. • In such cases there is no need for digestion • Examples : • Blood parasites • Protozoan parasites • Tapeworms • Acanthocephalans

5. Corals Most reef-building corals have a symbiotic relationship with photosynthetic algae, called zooxanthellae.which live in their gastrodermis tissue. The zooxanthellae convert sunlight, carbon dioxide, and water into oxygen and carbohydrates that feed the coral polyps and help them produce reef-building calcium carbonate. In return, the corals provide the zooxanthellae with protection and the compounds they need for photosynthesis. Pigments in zooxanthellae also give corals their beautiful orange, red, purple, and yellow colors.

6. Movement of substances into & out of unicellular organisms Passive diffusion in and out Bulk Transport requiring energy

7. Intracellular Digestion • In intracellular digestion, food particles are engulfed by endocytosis and digested within food vacuoles. • Protozoa, sponges.

8. CellSpecialisation in Simple Multicellular Organisms Sponge feeding

9. CellSpecialisation in Simple Multicellular Organisms Sponge feeding

10. Extracellular Digestion • Extracellular digestion is the breakdown of food particles outside cells. • Digestion occurs in the alimentary canal. • Cells lining the lumen of the alimentary canal are specialized for secreting enzymes or absorbing nutrients.

11. Intracellular v Extracellular Digestion

12. Cell Specialisation in Simple Multicellular Organisms

13. Cell Specialisation in Simple Multicellular Organisms Cnidarians feeding

14. Feeding Mechanisms – Particulate Matter • The upper portion of lakes and oceans contains very small animals and plants (plankton) that drift with the water currents. • Along with plankton, there is also organic debris floating in the water column and mixed in with the sediment. • Many organisms feed on this particulate matter.

15. Feeding Mechanisms – Particulate Matter • Suspension feeders use ciliated surfaces to create a current that draws drifting food particles into their mouths. • Many use mucous sheets to entrap food. • Tube dwelling polychaetes, • bivalve molluscs, hemichordates, protochordates.

16. Feeding Mechanisms – Particulate Matter • Others use sweeping movements of setae-fringed legs to create currents. • Fairy shrimp, daphnia, barnacles.

17. Feeding Mechanisms – Particulate Matter • Filter feeding is a form of suspension feeding that involves straining food from the water as it passes through a filtering device. • Herring, menhaden, basking sharks, flamingos, baleen whales.

18. Feeding Mechanisms – Particulate Matter • Deposit feeders consume the organic matter (detritus) that accumulates on the substratum. • Many annelids simply eat the substrate, digesting organic matter. • Others use appendages to gather organic deposits and move them to the mouth. • Scaphopods, sedentary or tube-dwelling polychaetes, some bivalves, some annelids.

19. Feeding Mechanisms • Predators have evolved a variety of ways to capture, hold, and swallow prey. • Many swallow food items whole. • Some have specialized teeth, beaks, or tooth-like structures. • Some have highly elastic jaws and distensible stomachs to accommodate large meals.

20. Cell Specialisation in Vertebrate Multicellular Organisms

21. Cell Specialisation in Vertebrate Multicellular Organisms

22. The different systems! Animal’s bodies are composed of different systems, each system has it’s own functions. All together these systems work together to enable the animal to survive. http://video.nationalgeographic.com/video/player/science/health-human-body-sci/human-body/human-body-sci.html

23. Obtaining nutrients and energy • Animals are heterotrophs must consume food in order to obtain nutrients and energy. • Animals are adapted to obtain food in a variety of ways python vs croc

24. Why We Eat • Regardless of what an animal eats, an adequate diet must satisfy three nutritional needs: • Fuel/ Energy for all cellular work. • Nutrients: • The organic raw materials for biosynthesis. • Essential nutrients, substances such as vitamins that the animal cannot make for itself.

25. Required Nutrients • Carbohydrates - source of immediate energy for all living organisms. The monosaccharide glucose is broken down to make ATP in cellular respiration. • Lipids- Fats and oils required for cell membranes, hormones and vitamins. • Amino Acids - The building blocks of proteins. The body can make some amino acids but others it can’t make these are the 9 essential amino acids. Need to be regularly eaten. • Vitamins - Organic compounds needed for cellular processes, e.g. making enzymes. • Minerals- needed for structural components and for enzyme molecules.

26. The Digestive System • Ingestion- intake of food into the body • Digestion- physical and chemical breaking down of food • Absorption- nutrient molecules move into the circulatory system and ultimately into the cells. • Egestion/ Elimination- removal of waste from the body

27. Two Types of Digestion. Physical digestion. • Food physically broken it down into smaller pieces in order to increase surface area and enable maximum efficiency of chemical digestion.

28. Teeth • Mammalian teeth are specialized for different functions. • Incisors – biting, cutting, stripping leaves. • Canines – seizing, piercing, tearing. • Premolars & molars – grinding and crushing.

29. Teeth • Mammalian teeth are specialized for different functions. • Incisors – biting, cutting, stripping leaves. • Canines – seizing, piercing, tearing. • Premolars & molars – grinding and crushing.

30. Feeding Mechanisms • Herbivorous animals have evolved special devices for crushing and cutting plant material. • Snails have a radula for scraping algae or plant material. • Insects have grinding & cutting mandibles.

31. Feeding Mechanisms • Herbivorous animals have evolved special devices for crushing and cutting plant material. • Mammals have wide corrugated molars for grinding.

32. Feeding Mechanisms • Fluid feeders may bite and rasp at host tissues, suck blood, and feed on contents of a host’s intestines. • Many have specialized tubelikemouthparts.

33. Chemical Digestion Breakdown of macromolecules by enzymes- made in the gut, salivary glands and pancreas into molecules small enough to be absorbed through the alimentary lining. Amylases- Break down starches into simple sugars Proteases- Break down protein-into amino acids Lipases- Break down lipids into glycerol & Fatty acids

34. Introduction to the Human Alimentary System animation Human digestion overview View animation then have a go at the quizzes and labelling exercises

35. Digestion • Stomach - majority of digestion occurs • Mechanical digestion occurs as the muscles crush and move the food. • Chemical digestion also occurs in the stomach, with the secretion of gastric juices with have enzymes that break down the food. • Small intestine -further digestion occurs but only on proteins and carbohydrates to break them down into their amino acid building blocks. Digestion-video.htm

38. Absorption Most occurs in the small intestine. Food at it’s smallest is then absorbed by the cells of the intestine and passed along to the blood stream.

40. Other mammals • Different diets require different digestive systems. • Breaking down cellulose requires the enzyme cellulase. • Mammals can’t make this enzyme. • Cows have a 4 chambered stomach. • They chew and then regurgitate their food and chew it again before sending it to the rumen where heaps of cellulose digesting bacteria live and allow the breakdown of the cellulose to occurs.

41. Carnivore v Herbivore Caecum: a pouch extension at the junction of the small & large colon which in herbivores contains cellulose digesting bacteria. Herbivorus mammals with higher fibre diets may have larger caecums to maximise the opportunity for cellulose digestion by bacteria.

42. Digestion in birds Most (not all) birds have : • a crop for temporary storage • a glandular part the proventriculuswhich secretes mucus , HCl & enzymes • a muscular gizzard which may contain grit or small stones which grinds and mixes the food and enzymes etc.