Organisms Within An environment Flashcards
What is competition between organism
Whenever one individual or species reduces the availability of limited resources for another individual or species. Organisms can compete over food, space, water, mates, soil nutrients, and light
What is the competitive exclusion principle
The ‘competitive exclusion principle’ (CEP) states that two species with identical niches cannot coexist indefinitely.
What is Exploitative competition
When consumption of a limited resources for one species makes it unavailable for another.
What is Intraspecific Competition and why is it more violent
Intraspecific competition is between organisms within the same species over similar resources. Intraspecific competition is much more violent than interspecific competition because the organisms in interspecific competition share the same or similar niche and would therefore depend on the same resources whereas in interspecific the organisms would be of different species meaning different niches so they can find alternative fir the resource if necessary.
Intraspecific competition decreases the reproduction rate and survival rate as the carrying capacity within the environment is approached.
What is interspecific Competition
Interspecific competition is competition between organisms within different species competing over the same resources. Competitors in this see reduces fecundity(the ability to produce an abundance of offspring, growth and survivorship.
Describe the 4 different types of relationships between organism
Predator-Prey: This is a relationship where the predator must kill and consume the prey for nourishment. Predators must be efficient enough to catch enough prey to survive and Prey must be efficient enough to escape to keep their numbers going.An increase in the predator population would mean a decrease in the prey population and vice versa.
Mutualism: Two organisms of different species interact and both benefit(cattle and egret) (Honey bee and flower)
Commensalism: Two organisms of different species interact one benefits and the other is unaffected (Gobies and Sea urchins)
Parasitism: One organism benefits and the other organism is negatively affected
(Dogs and Fleas/ticks)
What is adaptation
Adaptation is the ability of an organism to withstand extremes of physical conditions in the environment. Adaptation happens at 2 levels One being Aclimitisation where the physiological adaptations are neither permanent nor are they passed onto the offspring and are only at the individual level within a species and Two operating at the population level and is influenced by the inheritance of specific genetic traits that allow an organism to exist in its environment.
What is the role of natural selection in the evolution of species
Natural selection acts on a pre-existing genetic diversity, Selective pressures due to limited resources or environmental conditions favor advantageous genes. This leads to the survival of the fittest organisms which eventually reproduce successfully. Individuals with favorable genes may have more offspring surviving into the next generation. These carry the favourable genes which are available for passing on to the next generation.
What is the carrying capacity
The carrying capaacity is the maximum population size that can be sustained by a particular environment over a relatively long period of time.
When are transects used and describe the 2 types of transects
Transects are used to show the transition from one community to another and are used in areas that are zoned or have gradients
Line Transects are used when there is a need to investigate a possible linear pattern along which change in plant and animal communities is experiences. Compared to belt transects a line transect gives information on what is present but gives limited information on how much is present.
Belt Transects are used to give information on species abundance as well as presence ot absence of species. This is similar to the line transect except that is considered a widening of the line to form a continuous belt ot series of quadrats
What is a quadrat
A quadrat is a frame of known size 1m2 or 0.5m. Quadrats can be used to estimate a population an area which is fairly uniform. This is used for organisms which are non mobile. Quadrats produce 3 estimates percentage frequency percentage cover and population density.
