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IB DP Biology HL B4.2 Ecological niches Flashcards

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[h] IB DP Biology HL B4.2 Ecological niches Flashcards

 

[q] Ecological Niche

[a] The role of the species in an ecosystem


– Includes what it eats, when it is active, its habitat


– Includes ALL biotic & abiotic factors

 

[q] Fundamental Niche

[a] Potential niche of a species based on adaptations & tolerance limits

 

[q] Realized Niche

[a] The actual niche of a species when in competition with other species

 

[q] Example of Chthalamus vs. Semibalanus

[a] 1. The presence of Semibalanus affects the Chthalamus population


2. The presence of Chthalamus does NOT affect the Semibalanus population

 

[q] Competitive Exclusion

[a] One species will always go extinct if two species’ niches are the same

 

[q] Niche Partitioning

[a] There are a diversity of species on Earth, so each species occupy a slightly different niche;

these small differences allow for coexistence

 

[q] Obligate Aerobe

[a] Need/have to be in an area with atmospheric levels of oxygen

 

[q] Obligate Anaerobes

[a] Have to be in an environment in an area with lower than atmospheric levels of oxygen

 

[q] Facultative Anaerobes

[a] Can live in either areas with oxygen or without

 

[q] Autotroph(s)

[a] Produce carbon compounds from inorganic compounds using light or inorganic chemical energy;

uses external energy source


– Some prokaryotes


Algae: Huge group of organisms ranging from seaweed to single-celled algae (not a true clade)


– Plants


– Some archaeans

 

[q] Photoautotroph

[a] A type of autotroph that uses light to create organic compounds

 

[q] Chemoautotroph

[a] A type of autotroph that uses inorganic chemical energy to make carbon compounds (organic energy)

 

[q] Photosynthesis

[a] Conversion of light energy from the sun into chemical energy


– Used by not just plants, but also photosynthetic organisms

 

[q] Chemosynthesis

[a] Process by which ATP is synthesized by using chemicals as an energy source instead of light


– Used by things such as iron-oxidizing bacteria

 

[q] Light Energy

[a] Energy in the form of moving waves of light

 

[q] Chemical Energy

[a] Energy stored in chemical bonds

 

[q] Holozoic Nutrition

[a] A type of heterotrophic nutrition that involves the intake of complex organic matter, either as solids or liquids


– Food is ingested, digested internally, absorbed & assimilated (stored)


– Consumers

 

[q] Mixotrophs

[a] Can be both autotrophs & heterotrophs


– Some choose to do both; some have to do both


– Often protists (singled-celled eukaryotes)


– Euglena


– Ocean Plankton (Phytoplankton or zooplankton)

 

[q] Saprotrophs (Decomposers)

[a] Heterotrophs but not consumers


– Secrete enzymes to external environment & digest food externally


– Pull in digested nutrients only

 

[q] Archaeans

[a] Extremophiles
– Photoautotroph (use light)


– Chemoautotroph (oxidation of inorganic chemicals such as sulfur)


– Heterotroph (oxidation of carbon compounds)

 

[q] Tall trees

[a] Growth tall (canopy or emergent trees)

 

[q] Lianas

[a] Root in the ground & then wrap around trees to get higher

 

[q] Epiphytes

[a] Grow on other trees

 

[q] Strangler epiphytes

[a] Start on tree & then grow down into the ground, take nutrients from others

 

[q] Shade-tolerant shrubs

[a] Can absorb far red light that can reach the ground through the trees

 

[q] Hominidae Teeth

[a] Teeth differences reflect difference in diets

 

[q] Homo-sapiens

[a] Us, omnivores

 

[q] Paranthropus robustus

[a] Nutcrackers; people who eat nuts

 

[q] Homo-floresiensis

[a] Really small mouth, missing pre-molars

 

[q] Herbivores vs.Plants

[a] Herbivores evolve adaptations to feed on plants and plants evolve adaptations to resist herbivory

 

[q] Predators vs. Prey

[a] Predators evolve adaptations for finding, catching, & killing prey and prey animals evolve adaptations for resisting predation

 

[q] Niche

[a] The role of a species in an ecosystem

 

[q] Factors that affect niches

[a] All biotic and abiotic factors (Any interaction with other living things, as well as anything that affects its range of tolerance)

 

[q] Fundamental niche

[a] Potential niche of a species based on adaptations and tolerance limits.

 

[q] Realized niche

[a] The actual niche of a species when in competition with other species

 

[q] Competitive exclusion

[a] Theory that states that if two species occupy the same niche, one will go extinct because it is an inferior competitor

 

[q] Niche partitioning

[a] (For two species with similar niches) The coexistence of two species due to small differences in their niches

 

[q] Microorganisms

[a] Microscopic organisms

 

[q] Obligate

[a] Mandatory (used as an adjective to show that a condition is mandatory)

 

Ex: Obligate anaerobes must live in environments with low amounts of oxygen

 

[q] Obligate anaerobe

[a] Obligate = mandatory

 

An organism that must live in an environment without much oxygen (less than atmospheric levels of oxygen)

 

In case you’re curious (and also kind of helpful): an- “without”, aer- “air”, -obe (bios) “life”.

 

[q] Obligate aerobe

[a] An organism that must live in an environment with atmospheric levels of oxygen

 

[q] Facultative anaerobe

[a] An organism that can live in environments with or without oxygen

 

[q] Autotroph

[a] Organisms that produce carbon compounds from inorganic compounds using light or inorganic chemical energy (not just plants, and not just sunlight!)

 

[q] Examples of autotrophs

[a] Plants, algae, some prokaryotes (bacteria), some archaeans

 

[q] Algae

[a] A huge group of organisms ranging from seaweed to single celled algae (not a true clade)

 

[q] Holozoic

[a] Another word for consumers. They obtain nutrition by ingesting food, digesting it internally, absorbing it, and assimilating it

 

[q] Heterotroph

[a] An organism that obtains carbon compounds from other organic sources

 

[q] Mixotroph

[a] An organism that is capable of both photosynthesis and heterotrophy. Can be obligate mixotrophs (requiring both) or facultative mixotrophs (can use one or the other, or both)

 

[q] Examples of mixotrophs

[a] Mixotrophs are often protists (single celled eukaryotes)


Euglena (image)


Ocean Plankton


Venus Flytrap

 

[q] Saprotrophs

[a] Decomposers
Heterotrophs but not consumers because they secrete enzymes to the external environment and digest food externally,
rather than ingesting it.

 

They pull in only digested nutrients

 

[q] Examples of saprotrophs

[a] Some fungi and bacteria

 

[q] Domain of life

[a] The three major groupings of organisms: bacteria, eukaryotes, and archaeans

 

[q] Archaeans

[a] Extremophiles (-phile “loving”, so extreme condition loving organisms)

 

[q] Archaea nutrition types

[a] – Light


– Oxidation of inorganic chemicals such as sulfur


– Oxidation of carbon compounds

 
 

[q] Liana

[a] Plant that roots in the ground and wraps around trees to get higher

 

[q] Epiphyte

[a] Plant that takes root on and grows on other trees (“epi-” = on, “-phyte” = plant)

 

[q] Strangler epiphyte

[a] Plant that takes root on the tree and then grows down into the ground, taking nutrients from it

 

[q] Shade-tolerant shrubs

[a] Shrubs that can absorb far red light that reaches the ground through the trees

 

[q] Homo florensiensis teeth

[a] Small mouth, missing pre-molars

 

[q] Relationship between dentition (teeth) and diet

[a] Carnivores have sharp teeth, herbivores have flat teeth, omnivores have a mix of both

 

Will need to deduce a hominid’s diet from its skull

 

[q] Examples of adaptations for herbivores feeding on plants and of plants for resisting herbivory

[a] Herbivores: Leaf-eating insects feature piercing and chewing mouthparts. Flat teeth help to chew leaves as well.


Plants: Some plants use thorns and other physical structures. Other plants produce toxic compounds in leaves and seeds. Some herbivores have metabolic adaptations to detoxify these toxins, however.

 

[q] Examples of adaptations for predators hunting prey

[a] Physical, chemical, and behavioral adaptations


Examples: Fast speed, nimble body, resistance to prey’s toxins, infection resistance, camouflage, calls/sounds (sometimes the lack thereof), sharp claws

 

[q] Examples of adaptations for prey resisting predation

[a] Includes physical, chemical, and behavioral adaptations


Examples: Poison, fast speed, camouflage, quills, chemical signaling to warn of predators, etc.

 
 

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IB DP Biology HL B4.2 Ecological niches Flashcards

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