Heterotrophic Nutrition

1. Heterotrophic Nutrition www.assignmentpoint.com

2. Introduction • unable to derive energy from photosynthesis or from inorganic chemical reactions, and so dependent on energy-containing organic compounds derived from the current or prior existence of other organisms, cf. AUTOTROPHIC.www.mycolog.com/GLOSSARY.htm • Describing consumers, organisms that cannot synthesize food from inorganic materials and therefore must use the bodies of other organisms as a source of energy and body-building materials.*biology.usgs.gov/s+t/noframe/z999.htm • An organism incapable of producing organic compound from inorganic materials and thus must rely on other living or dead organisms for its food supply.www.botanyvt.com/pages/dictionary.shtml • requiring ready formed organic food.gmbis.marinebiodiversity.ca/BayOfFundy/glossE-H.html www.assignmentpoint.com

3. Source of Carbon www.assignmentpoint.com

4. Source of Carbon www.assignmentpoint.com

5. Source of Carbon • The concentration of carbon in living matter (18%) is almost 100 times greater than its concentration in the earth (0.19%). • So living things extract carbon from their nonliving environment. For life to continue, this carbon must be recycled. www.assignmentpoint.com

6. Source of Carbon Carbon exists in the nonliving environment as: • Carbon dioxide (CO2) in the atmosphere and dissolved in water (forming HCO3−) • Carbonate rocks (limestone and coral = CaCO3) • Deposits of coal, petroleum, and natural gas derived from once-living things • Dead organic matter, e.g., humus in the soil www.assignmentpoint.com

7. Source of Carbon Carbon enters the biotic world through the action of autotrophs: • primarily photoautotrophs, like plants and algae, that use the energy of light to convert carbon dioxide to organic matter. • and to a small extent, chemoautotrophs — bacteria and archaeans that do the same but use the energy derived from an oxidation of molecules in their substrate. www.assignmentpoint.com

8. Source of Carbon Carbon returns to the atmosphere and water by • Respiration (as CO2) • Burning • Decay (producing CO2 if oxygen is present, methane (CH4) if it is not. www.assignmentpoint.com

9. Source of Carbon www.assignmentpoint.com

10. Source of Carbon www.assignmentpoint.com

11. Source of Carbon Definitions of Chemoheterotroph on the Web: • A chemoheterotroph is an organism that must consume organic molecules for both energy and carbon. en.wikipedia.org/wiki/Chemoheterotroph www.assignmentpoint.com

12. Omnivores www.assignmentpoint.com

13. Omnivores • Omnivores eat plants, but not all kinds of plants. • Omnivores can't digest some of the substances in grains or other plants that do not produce fruit. • They can eat fruits and vegetables, though. Some of the insect omnivores in this simulation are pollinators, which are very important to the life cycle of some kinds of plants. Large Omnivores www.assignmentpoint.com

14. Omnivores www.assignmentpoint.com

15. Omnivores • Some animals don’t fit neatly into a single category because they have wider tastes. These animals, that feed on a combination of plants and animals, are called Omnivores. www.assignmentpoint.com

16. Carnivores www.assignmentpoint.com

17. Symbiosis Most of the interactions between species involve food: • competing for the same food supply • eating (predation) • avoiding being eaten (avoiding predation) www.assignmentpoint.com

18. Symbiosis In symbiosis, at least one member of the pair benefits from the relationship. The other member may be • injured = parasitism • relatively unaffected ( = commensalism) • may also benefit ( = mutualism). www.assignmentpoint.com

19. Symbiosis Mutualism • Symbiotic relationships in which each species benefits are mutualistic. There are hundreds of examples of mutualism between a heterotroph and an alga. www.assignmentpoint.com

20. Symbiosis • Paramecium bursaria is a ciliate that engulfs unicellular green algae into vacuoles within its cell. • The paramecium certainly benefits from the food synthesized by the alga. It can be cultured apart from the alga but then must be given extra food. • The alga presumably benefits from the carbon dioxide produced by its host as well as the host's ability to transport it to a spot where there is ample light. www.assignmentpoint.com

21. Symbiosis • Many other aquatic heterotrophs • sponges • sea anemones • planarians • clams • also harbor algae within their cells. www.assignmentpoint.com

22. Symbiosis • liberating toxins, for example, • Tetanus bacilli secrete tetanus toxin which interferes with synaptic transmission. • Diphtheria bacilli secrete a toxin that inhibits protein synthesis by ribosomes. • The relationship between parasite and host varies along a spectrum that extends from www.assignmentpoint.com

23. Symbiosis • Mutualistic relations between plants and fungi are very common. The fungus invades and lives in or among the cortex cells of the secondary roots. The association is called a mycorrhiza. www.assignmentpoint.com

24. Symbiosis • The fungus helps the host plant absorb inorganic nitrogen and phosphorus from the soil. Some mycorrhizal fungi also secrete antibiotics which may help protect their host from invasion by parasitic fungi and bacteria. www.assignmentpoint.com

25. Symbiosis • Many mushrooms are the spore-forming bodies of mycorrhizal fungi. The truffle [View] is often found in oak forests because the fungus that produces it establishes mycorrhiza on oak roots. www.assignmentpoint.com

26. Symbiosis Parasitism • A parasite is an organism that • lives on or in the body of another organism (the host) • from whose tissues it gets its nourishment, and • to whom it does some damage www.assignmentpoint.com

27. Symbiosis • "hit and run" parasites that live in their host for a brief period and then move on to another with or without killing the first to • parasites that establish chronic infections. Both parasite and host must evolve to ensure the survival of both because if the parasite kills its host before it can move on, it destroys its own meal ticket. • Link to further discussion. www.assignmentpoint.com

28. Symbiosis • Animals are parasitized by viruses, bacteria, fungi, protozoans, flatworms (tapeworms and flukes), nematodes, insects (fleas, lice), and arachnids (mites). • Plants are parasitized by viruses, bacteria, fungi, nematodes, and a few other plants. • Parasites damage their host in two major ways: • consuming its tissues, e.g., hookworms www.assignmentpoint.com

29. Feeding Mechanism www.assignmentpoint.com

30. Feeding Mechanism How a filter feeder obtains food: • Stream of water carries particles/food • In through siphon • Mucus on gills traps particles • Cilia transport particles/water current (along food groove) towards mouth • Enzymes in intestine breakdown food • Carbohydrates absorbed as monomers The Antarctic krill manages to directly utilize the minute phytoplankton cells www.assignmentpoint.com

31. Feeding Mechanism How a filter feeder creates a feeding current: • Cilia • Beating/ moving rhythmically www.assignmentpoint.com

32. Feeding Mechanism Extra-cellular digestion: • Body consists of thin threads (hyphae) • Hyphae secrete enzymes that diffuse through wall onto food • Enzymes hydrolyse materials in food to monomers • Monomers then absorbed into hyphae by F.D. and A.T. • In fungi (e.g. saprophytic fungi), cilia not involved in moving food www.assignmentpoint.com

33. Feeding with Tentacles • When feeding, these animals project tentacled structures out of the tube to catch food particles in the flowing water. By using cilia on their tentacles, these worms select particles based on size. www.assignmentpoint.com

34. Detritus feeding • detritus, consists of bacteria and the remains of finely chopped up algae and decaying fragments of animals, as well as countless numbers of stranded microscopic, one-celled green plants which are called diatoms. www.assignmentpoint.com

35. Biting & Chewing Mouthpart • Biting and chewing food is a multisensory task that requires a high level of coordination of all parts of the mouth. www.assignmentpoint.com

36. Biting & Chewing Mouthpart • chewing mouthparts have toothed jaws that bite and tear the food (beetles, cockroaches, ants, caterpillars, and grasshoppers). • piercing-sucking mouthparts are usually long slender tubes that are forced into plant or animal tissue to suck out fluids or blood. (mosquitoes, aphids). • sponging mouthparts are tongue-like structures that have spongy tips to suck up liquids or food that can be made liquid by the insect's vomit (house flies, blow flies). • siphoning mouthparts are long tubes used for sucking nectar (butterflies, moths). www.assignmentpoint.com

37. Fluid feeding • An external type of digestion is sucking or fluid feeding. A wide variety of animals and insects are adapted to take in liquid food, either from plants or animal juices. All spiders use sucking as their digestive means. They inject digestive enzymes into the prey and allow the exoskeleton to contain the juice as internal body parts are liquified. www.assignmentpoint.com

38. Herbivorous Strategies • Cranial fermentors or ruminants have a large, multicompartmented section of the digestive tract between the esophagus and true stomach. These forestomachs house a very complex ecosystem that supports fermentation. Examples of ruminants are cattle, sheep and deer. • Caudal fermentors, also known as cecal digestors, are similar to dogs and humans through the stomach and small intestine, but their large intestine, where fermentation occurs, is complex and exceptionally large. Examples of cecal digestors include horses and rabbits. www.assignmentpoint.com

39. Herbivorous • Ruminants can utilize dietary starch, but very little of it is absorbed as glucose. • Rather, starch and other soluble carbohydrates are fermented to volatile fatty acids in the forestomachs. • In contrast, starch fed to a horse is digested to glucose by amylase and maltase in the small intestine, and that glucose is absorbed across the epithelium into blood. www.assignmentpoint.com

40. Herbivorous www.assignmentpoint.com