2.1 Species and Population Flashcards
Define Biotic Components
The living components of an ecosystem. Examples include animals, plants, fungi, etc.
Define Abiotic Components
The non living components of an ecosystem. Examples include temperature, sunlight, water, etc.
Define Species
A group of organisms that share common characteristics and can interbreed to produce fertile offspring. Examples include humans, leopards, pea plants, etc.
Define Population
A group of organisms of the same species that live in the same area at the same time, and which are able to interbreed. Three factors affect population size: birth rate, death rate, and migration.
Define Limiting Factor
A resource in limited supply that can affect the growth of a population.
Define Carrying Capacity
The number of individuals in a population that the resources in the environment can support for an extended period.
Define Population Dynamics
The study of the change in populations over time.
Define Niche
The particular environment and “lifestyle” that a species has. It includes the place where the organism lives and breeds, its food and feeding method, activity patterns and interactions with other species.
Define Fundamental Niche
The potential mode of existence of the species, given its adaptation.
Define Realized Niche
The actual mode of existence of a species which results from its adaptation and competition from other species - that is, its actual lifestyle due to biotic interactions. A realized can only be the same size or smaller than the fundamental niche.
Define Habitat
The environment in which a species usually lives. For example, the habitat of an orangutan is the rainforest of Borneo.
Define Competition
Competition is when individuals compete for resources such as food and space.
Define Intraspecific Competition
Population may compete with members of their own species.
Define Interspecific Competition
Populations may compete with members of other species that use the same resources.
Define Predation
Predation is an interaction between species in which one species, the predator kills and eats another, the prey.
Define Herbivory
Herbivorous animals feed only on plants.
Define Parasitism
Parasitism is a relationship on which one organism, the parasite, benefits from another, the host, which may suffer as a result of the parasite’s presence.
Define Mutualism
Mutualism is a relationship between two organisms that gives benefit to both.
Define the Lag Phase in a S or J Curve
When organisms become adapted to the conditions (medium).
Define the Exponential Growth Phase in a S or J Curve
The period in which there are no limiting factors and the population can double in size in set time periods, which depend on the species.
Define the Transition Phase in a S or J Curve
When a resource starts to becoming limiting and the rate of growth decreases.
Define the Plateau Phase in a S or J Curve
When a population has reached stable, sustainable numbers, with births and immigration approximately equal to deaths and emigration.
