Interactions Affect Survival - Middle School Life Science
- Identify the interaction: bees pollinate flowers and both benefit.
- Mutualism. Bees get nectar; flowers get pollinated—both benefit.
- What is the best evidence that competition has increased in a population over time?
- Lower growth or fewer offspring as density rises. Competition intensifies with crowding, reducing reproductive success.
- Identify the interaction: ticks feed on a deer, weakening the deer but not killing it.
- Parasitism. Ticks benefit by feeding on blood while harming but not killing the host.
- What is the term for a trait that helps an organism avoid predators and survive?
- Adaptation. Inherited traits that increase survival chances in specific environments.
- Identify the interaction: clownfish gain shelter in anemones; anemones gain protection.
- Mutualism. Both species benefit: shelter for clownfish, defense for anemones.
- Which evidence best supports parasitism rather than mutualism?
- One species benefits while the other shows reduced health or fitness. Parasitism harms the host while benefiting the parasite.
- What is competition in ecology?
- Organisms vie for the same limited resource. Limited resources force species to compete for survival.
- What is commensalism in ecology?
- One species benefits and the other is unaffected. The unaffected species neither gains nor loses from the interaction.
- What is the term for an interaction where one organism kills and eats another organism?
- Predation. The predator gains food by hunting and consuming prey organisms.
- Which evidence best supports mutualism between two species?
- Each species has higher survival or reproduction when together. Mutualism enhances fitness for both participating species.
- Identify the limiting resource most likely involved: plants grow smaller in crowded plots.
- Light (reduced access due to shading). Crowded plants compete for sunlight, limiting photosynthesis.
- What is the term for two species using different resources or times to reduce competition?
- Resource partitioning. Species divide resources by space, time, or type to avoid competition.
- Identify the interaction: barnacles live on a whale; the whale is not helped or harmed.
- Commensalism. Barnacles gain a mobile surface to live on without affecting the whale.
- Identify the interaction: a tick feeds on a dog and harms it.
- Parasitism. Tick gains blood meal while dog loses nutrients and health.
- What is the term for an interaction where both organisms benefit and survival increases?
- Mutualism. Both species gain benefits, improving their chances to survive and reproduce.
- Which evidence best supports that camouflage increases survival in a prey species?
- Camouflaged individuals are eaten less often. Lower predation rates directly show improved survival from camouflage.
- What is the most direct survival advantage of living in a group when predators are present?
- Reduced chance of being captured by predators. Groups provide safety through dilution effect and increased vigilance.
- What is an adaptation (in the context of survival and reproduction)?
- An inherited trait that increases fitness. Fitness measures reproductive success, not just survival.
- What is a limiting resource that can cause competition and reduce reproduction rates?
- Food, water, space, shelter, or mates. When scarce, these resources trigger competition between organisms.
- What is the term for an interaction where one organism benefits and the other is unaffected?
- Commensalism. One species gains a benefit while the other experiences no harm or help.
- Which outcome best indicates resource partitioning between two bird species in one habitat?
- Each species feeds in different areas or on different foods. Using different resources shows they've partitioned to reduce competition.
- What is the main outcome of intense competition between two species with the same niche?
- Competitive exclusion: one outcompetes the other. Two species cannot coexist if they occupy identical niches.
- What is the term for an interaction where one organism benefits and the other is harmed?
- Parasitism. The parasite gains nutrients while weakening or damaging its host organism.
- What is mutualism in ecology?
- An interaction where both species benefit. Both organisms gain resources or protection from the relationship.
- Which interaction is density-independent: competition, parasitism, or wildfire?
- Wildfire. Wildfires affect all organisms equally regardless of population density.
- What is the term for organisms needing the same limited resource, reducing fitness?
- Competition. Organisms struggle for scarce resources, reducing survival and reproduction.
- What is predation in ecology?
- One organism kills and eats another organism. Predators consume prey for energy and nutrients.
- Identify the interaction: barnacles live on a whale; whale is unaffected.
- Commensalism. Barnacles gain transport; whale experiences no harm or benefit.
- What does fitness mean in natural selection?
- Ability to survive and produce fertile offspring. Fitness determines which traits pass to the next generation.
- What is a niche?
- A species' role and resource use in its ecosystem. Includes habitat, food sources, and behaviors unique to that species.
- Which interaction most directly decreases survival of the prey organism?
- Predation. Predators kill prey, directly reducing prey survival.
- What is a limiting resource?
- A resource in short supply that restricts population growth. Populations cannot grow beyond what limiting resources support.
- Identify the interaction: a hawk catches and eats a mouse, decreasing mouse survival.
- Predation. The hawk kills the mouse for food, reducing mouse population survival.
- Which evidence best supports that a parasite lowers host reproductive success?
- Infected hosts produce fewer viable offspring. Reduced offspring production directly shows reproductive harm from parasites.
- Which interaction is density-dependent: predation, drought, or earthquake?
- Predation. More prey in an area attracts more predators, making it density-dependent.
- Which evidence best supports competition: two species show reduced growth when together?
- Both species grow better when separated than when together. Competition reduces growth when species share limited resources.
- What is parasitism in ecology?
- One species benefits while the host is harmed. Parasites extract nutrients or resources, weakening the host.
- Which interaction can increase reproduction by aiding mate attraction within a species?
- Cooperation (intraspecific interaction). Group behaviors like displays or calls help attract mates.