Ecosystem Interactions and Relationships

The video tutorial covers biotic factors, focusing on interactions among species in ecosystems. It explains positive interactions like mutualism and commensalism, where species benefit or remain unaffected. Negative interactions such as predation, parasitism, and competition are also discussed, highlighting how these interactions impact species and ecosystems. The tutorial provides examples to illustrate these concepts, helping to understand ecological dynamics and predict human impacts on ecosystems.

What is the primary role of biotic factors in an ecological community?

• To provide energy to the ecosystem

• To form the basis for biological processes

• To supply nutrients to the soil

• To regulate the climate

In mutualism, how do both species benefit?

• One species is harmed while the other benefits

• Both species compete for resources

• Both species gain benefits from the association

• One species is unaffected while the other benefits

Which of the following is an example of commensalism?

• Predator and prey

• Lichen and fungus

• Orchids growing on trees

• Parasitic wasp and caterpillar

What characterizes a negative interaction in an ecosystem?

• Both species benefit

• One species benefits while the other is harmed

• Both species are unaffected

• One species is harmed while the other is unaffected

Which plant is known as a total stem parasite?

• Sandalwood

• Venus flytrap

• Cuscuta

• Nepenthes

What is the main difference between intra-specific and inter-specific competition?

• Intra-specific involves mutual benefits, inter-specific involves harm

• Intra-specific occurs between different species, inter-specific within the same species

• Intra-specific occurs within the same species, inter-specific between different species

• Intra-specific is always beneficial, inter-specific is always harmful

Which of the following is an example of inter-specific competition?

• Two lions fighting for territory

• A fungus inhibiting bacterial growth

• Different herbivores competing for the same food source

• A tree shading out smaller plants

What is amensalism?

• A relationship where both species are harmed

• A relationship where one species is harmed and the other is unaffected

• A relationship where one species benefits and the other is unaffected

• A relationship where both species benefit

Which chemical is produced by Penicillium to inhibit bacterial growth?

• Lignin

• Tannin

• Penicillin

• Alkaloid

What is the effect of allelopathic substances in amensalism?

• They promote growth of other plants

• They inhibit growth of other species

• They provide nutrients to the soil

• They attract pollinators