Unit 6.1 - Ecological Niches Flashcards
Ecological Niches
Ecological niches
The role of a species within its habitat
Biotic
Living factors that affect the survival of other organisms
Abiotic
Nonliving parts of an ecosystem that can affect the survival of organisms
Obligate anaerobes
Single-celled organisms that can only carry out anaerobic respiration and cannot survive in the presence of oxygen
Facultative anaerobes
These organisms may respire aerobically, but have the ability to switch fully to anaerobic respiration in the absence of oxygen which has no negative effects on them
Obligate aerobes
Organisms that cannot survive in the absence of oxygen and rely on aerobic respiration to release energy from food.
Photosynthesis
The use of light energy to convert carbon dioxide from the air into organic molecules such as carbohydrates
Prokaryote
Single-celled organisms that have a simple cell structure without compartmentalisation (they do not possess any membrane-bound organelles)
Autotrophic nutrition
An autotroph synthesises or produces its own organic molecules from simple, inorganic substances in its environment
Heterotrophic nutrition
A heterotroph gains organic molecules from the tissues of other organisms
Holozoic nutrition
The gaining of organic molecules by ingesting, digesting, absorbing and assimilating molecules from the tissues of other organisms
Mixotrophs
Mixotrophs are organisms that are able to make use of more than one method of nutrition, such as auto- and heterotrophy
Obligate mixotrophs
Must constantly have access to both methods of nutrition
Facultative mixotrophs
Can survive using one method of nutrition, which is supplemented by the other
Saprotrophic nutrition
Are heterotrophs that ingest the tissues of dead organisms and waste material by secreting enzymes onto their food and digesting it externally before absorbing the products of their digestion
Decomposer
Organisms that feed on dead or decaying organisms as an energy source
Archaea
Are a diverse group of single-celled organisms that make up one of three domains. Phototrophic, chemolithotrophic and heterotrophic archaea
Phototrophs
Uses energy from light to generate ATP
Chemolithotrophs
Uses energy from chemicals to generate ATP
Organotrophs
An organism that obtains hydrogen or electrons from organic substrates
Omnivore
Nutrition comes from a combination of animal and plant material
Herbivore
Heterotrophs that feed on plants
Family Hominidae
The family of humans and their closest relatives, including: chimpanzees, gorillas, orangutans and gibbons
Predators
Are animals that hunt and eat other animals or consume the tissues of recently dead animals
Prey
Are animals that are hunted and consumed by predators
Camouflage
The different ways animals try to hide their identity or appearance from other animals
Venom
Venom contains toxins that immobilise or kill the prey animal e.g snakes or scorpions (predators)
Mimicry
Allows prey animals to look like predators. e.g owl butterflies have wing patterns that resemble the eye of an owl
Nocturnal
Active during the night time
Diurnal
Active during the daytime
Lianas
Are woody vines that use the trunks of trees as their main supporting structure to gain height, allowing their leaves to reach the forest canopy where they can absorb light for photosynthesis. They germinate on the forest floor and grow towards the base of the tree trunks before growing upwards.
Epiphytes
Use the hight of trees to increase their absorption of sunlight by growing high up in the tree branches, but they do not begin their lives on the forest floor, and often gain their nutrients from high up in the canopy. They avoid having to expend energy on upward growth.
Strangler Epiphytes
Similar to epiphytes as they start life in the canopy. However, they grow roots downwards to the forest floor, allowing them to gain nutrients and water from the soil. While still taking advantage of height from trees to absorb sunlight.
Shade tolerant plants
Grow on the forest floor and are adapted to absord the limited range of light wavelengths that reach the ground through the leaves of the canopy and understory. They may contain different photosynthetic pigments, allowing them to absorb different wavelengths of light. They also have large leaves to maximise the surface area for light absorption
Fundamental niche
The niche a species would occupy if there were no limiting factors in the environment or resources the species could use
Realised niche
The niche that a species actually occupies in the presence of competitor species
competitive exclusion
The elimination of a competing species from its niche. A niche can only be occupied by one species, meaning that every individual species has its own unique niche, if 2 species occupy the same niche, they will compete with each other for the same resources and eventually one of the species will out-compete the other.
