1. Symbiosis: Organisms can have close ecological relationships in ecosystems Mutualism (+,+) both organisms benefit from the relationship Remoras clean sharks The remoras get food & protection The sharks get clean TAKS Obj.3: Bio 12b Symbiosis

2. Commensalism (+,0) one organism benefits, other is not affected Ex. Spanish moss grows on trees receiving light & nutrients from the air The tree is not helped or harmed

3. Parasitism (+,-) one organism benefits, other is harmed. The organism being harmed is called the host. Parasites may weaken, but usually don’t immediately kill their host EX.The tick receives food, the dog is bitten Other Interactions (not symbiosis) Predation: When a predator (like a carnivore or omnivore) hunts another organism, called its prey, for food

4. 1 According to the information in the box, which of these BEST describes the relationship between the ant & Acacia tree? A Parasitism B Predation C Commensalism D Mutualism Remember, the ants get nutrition (food). The plants get protection. Each organism benefits… Mutualism (+,+) READ! Search for clues in the question. Find the key sentence in the reading passage. In the jungles of Costa Rica, a certain species of ant live in a complex relationship with the Acacia tree. The ants find shelter in the hollow thorns of the plant. They attack any animal that tries to feed on the tree. In return, the plant provides them with nutrition.

5. Symbiosis Simulation Which form of symbiosis is shown in the following examples? Hold up the correct pair of cards: Mutualism (+,+), Commensalism (+,0) or Parasitism (+,-) 1. A hummingbird feeds on the nectar of flowering plants, while spreading the plant’s pollen to other flowers. 2. A cattle bird feeds on insects stirred up by the feet of the cows that they live with. 3. Mistletoe grows in an elm tree, absorbing nutrients meant for the branches. 4. A desert wasp shoots its eggs into the burrows of bees, where they hatch into larvae and feed on the bee’s eggs. (+,+) (+,0) (+,-)

6. Symbiosis Simulation 5. E.coli bacteria live in the large intestines of humans. They receive nutrients from food wastes and produce vitamin D which is absorbed by the host. 6. The stinging tentacles of the sea anemone protect pairs of clown fish. In return, the clown fish clean debris from the sea anemone. 7. Strangler figs start when a bird or fruit bat drops a seed onto a live tree. Its roots grow quickly downward, choking the host tree and taking its nutrients, while its crown grows upwards, stealing sunlight. 8. Tapeworm eggs are passed by flea bites to the blood stream of dogs. After hatching, they absorb nutrients from the small intestine. (+,+) (+,+) (+,-)

7. Symbiosis Simulation 9. Barnacles often attach themselves to whales and filter food from the water as the whale swims. 10. The desert yucca plant depends on a moth to pollinate its flowers, and the moth depends on the yucca plant as a place to lay its eggs so the developing larva will have an available food source. 11. A hermit crab uses the abandoned shell of snails as a home. 12. Cattle often graze in fields of grass. While the cattle are fed, their hooves poke holes in the soil allowing oxygen, water, and nutrients to enter the soil easily. Without these nutrients, the soil develop a hard crust. The cows also provide natural fertilizer for the growing grass. (+,0) (+,+) (+,+)