A3.2 Ecological Niche

ecological niche

where an organism lives but also on what it does, its role and its impacts on the ecosystem.

biotic factors

the living parts of an ecosystem. refers to the interactions with the living parts of the environment such as competition with other species for resources, disease, predators and parasites.

abiotic factor

the non-living parts of the ecosystem such as the temperature, precipitation, wind, the amount of sunlight, the pH of the water, and the soil that the organism lives in.

obligate anaerobes

Organisms that can only survive in environments that lack oxygen. Use other electron acceptors for respiration like sulfate, nitrates, iron, manganese, mercury or carbon monoxide. lack the certain enzymes that deal with oxygen, making it toxic.

facultative anaerobe

Organisms that can survive in environments that contain or lack oxygen. can use alternative electron acceptors in ETC. Have higher ATP yield in aerobic conditions

obligate aerobe

Organisms that can only survive in environments that contain oxygen. oxygen is the final electron acceptor

experiment to find respiration type

growing bacteria in a special culture medium containing thioglycolate.

Autotrophs

Organisms that are able to make their own food. also known as primary producers

heterotrophs

An organism that obtains nutrition from external sources, like other organisms also know as consumer

photosynthetic nutrition

when autotrophs use photosynthesis to generate energy from sunlight. they often have chloroplast containing chlorophyll to capture the light energy

holozoic nutrition

Type of nutrition used by heterotrophs involving ingestion of liquid or solid organic food particles for growth and development.

mixotrophic nutrition

Combination of autotrophic and heterotrophic nutrition. used by mixotrophic organisms like marine plankton.

facultative mixotroph

can switch between autotrophic and heterotrophic modes of nutrition depending on the conditions within the environment.

obligate mixotroph

require both autotrophic and heterotrophic modes of nutrition to survive

saprotrophic nutrition

used by organisms like fungi and bacteria. a method by which the organism secretes digestive enzymes that are able to break down the dead organic material into simpler molecules that are then absorbed

Chemoautotrophs or chemolithotrophs

prokaryotes that use inorganic chemicals as their energy source. use oxidation of inorganic chemicals such as sulfur, hydrogen sulfide, iron or ammonia for their metabolism

extremophiles

Archaea that live in extreme environments.

archaea

Domain of unicellular prokaryotes that have cell walls that do not contain peptidoglycan but instead made of polysaccharides

phototrophs

organisms that get energy from light

organotrophs

oxidize organic compounds, such as

sugars and fatty acids, to produce ATP.

dentition

Natural teeth in the dental arch

hominins

all modern and extinct humans and their immediate ancestors

hominoids

not only the hominins but also the great apes

herbivores

An organism that obtains its nutrition by consuming plants or plant material

omnivore

An organism that is adapted to eat both plant and animal material for nutrition.

family Hominidae

Family of great apes, including humans.

carnivores

An organism that relies on eating other organisms for nutrition.

predator

An animal that hunts other animals for food

prey

An organism that is killed and eaten by another organism

prey adaptations

retreat, camouflage, warning coloration, poison, mimicry, armor/protective coverings, agility and swiftness, group travel/ swarm, alarm calls, nocturnal or diurnal

predator adaptations

Camouflage, speed and agility, hunting in packs, poisons, acute senses, claws, powerful jaws, ambush tactics

camoflage

an adaptation that enables a species to blend in with its environment

venom

a poisonous secretion

mimicry

morphological adaptation in which one species evolves to resemble another species for protection or other advantages

nocturnal

active at night

diurnal

active during the day

epiphytes

Plants that grow on the surface of other plants using them only for support. For example, orchids. live on other plants to get nutrients and water from the air.

strangler epiphytes

start on tree and then grow down into the ground, take nutrients from the host species

shade tolerant plants

Plants in forest ecosystems, like those in the herb layer, have adaptations (e.g., large thin leaves) to maximize light absorption in low-light environments.

fundamental niche

The ideal environmental conditions where an organism can live and reproduce, considering both abiotic (non-living) and biotic (living) factors.

realized niched

The actual living and reproducing conditions of an organism, which are constrained by factors like competition with other species. The realised niche is smaller than the fundamental niche due to these pressures.

competitive exclusion (Gause's law)

Two species cannot occupy the same niche indefinitely. One species will outcompete the other. Over time, competition for resources results in the exclusion or adaptation of one species.

niche partitioning

the way competing species adapt to share a habitat by occupying different niches or parts of the same niche.

spatial partitioning

Species evolve to use different physical spaces within the same habitat, reducing competition for resources.

temporal partitioning

Species evolve to use the same area at different times, reducing direct competition for resources.

decomposer

an organism, like fungi or bacteria, that breaks down dead organic matter, releasing nutrients back into the environment.