Ecological Niches and Nutrition

Flashcards related to Ecological Niches B4.2, covering ecological niches, nutrition types (holozoic, mixotrophic, saprotrophic), adaptations, and dentition relationships across species.

Ecological Niche

The role of a species in an ecosystem, encompassing both biotic and abiotic elements.

Biotic Factors

Living or once-living things, such as plants, animals, fungi, and bacteria.

Abiotic Factors

Nonliving things, such as rocks, elements, wind, sun, and weather.

Zones of Tolerance

Abiotic factors that determine the habitat of an organism.

Obligate Aerobes

Require a continuous oxygen supply and only live in oxic environments.

Obligate Anaerobes

Are inhibited or killed by oxygen, so they only live in anoxic environments.

Facultative Anaerobes

Use oxygen if available but can also live in anoxic environments.

Photosynthesis

The process where sunlight energy is used to fix carbon and create sugars; mode of nutrition in plants, algae, and some prokaryotes.

Autotrophs

Organisms that perform photosynthesis.

Holozoic Nutrition

Nutrition where whole pieces of food are ingested and digested into smaller compounds, typical of animals.

Heterotrophic

Organisms that obtain food from other sources.

Mixotroph

Organisms that can be classified as both autotrophs and heterotrophs, using both methods of nutrition.

Facultative Mixotroph

Can use both autotrophic and heterotrophic modes of nutrition but don't have to.

Obligate Mixotroph

Must use both autotrophic and heterotrophic modes of nutrition to grow and survive.

Saprotrophs

Secrete digestive enzymes into dead matter externally and then absorb the products of digestion; many bacteria and fungi.

Decomposers

Digest dead matter externally.

Phototrophic (Archaea)

Use light to make energy, but use molecules other than chloroplasts.

Chemotrophic (Archaea)

Oxidize chemicals to make energy.

Heterotrophic (Archaea)

Obtain carbon compounds from ingesting food.

Fundamental Niche

The range of biotic and abiotic conditions an organism can tolerate; the potential niche.

Realized Niche

The actual extent of the potential range where an organism lives due to competition.

Competitive Exclusion

When fundamental niches overlap, leading to competition; one species may be excluded if outcompeted in all parts of the niche.

Trees (Light Adaptation)

Dominant shoot grows rapidly to reach the top of the forest canopy for light.

Lianas (Light Adaptation)

Climb through other trees, using them for support to reach light.

Epiphytes (Light Adaptation)

Grow on trunks and branches of trees to be higher than the forest floor for light.

Strangler Epiphytes

Climb up trees, outgrow them, and shade the tree, leading to its death.

Shade-Tolerant Shrubs

Absorb light reaching the forest floor.

Herbivore

Animal feeding exclusively on plants.

Plant defense against herbivory

Spines, thorns, toxins that prevent herbivores from eating plants.

Predator-Prey Adaptations

Structural, chemical, behavioral adaptations to find prey or resist predation.

Structural adaptations

Adaptations that require long periods of time and genetic changes like mutations.

Chemical adaptations

Adaptations that are slowest to change, potentially requiring new enzymes.

Behavioral adaptations

Adaptations that change quickly due to environmental pressures.

Herbivore dentition

Flat, large teeth to grind fibrous plants; seen in herbivores.

Omnivore dentition

Mix of flat and sharp teeth to grind plants and tear through meat; seen in omnivores.