Variation in population size

Beschreibung

A-Levels Biology 4 (Ecosystems and populations) Mindmap am Variation in population size, erstellt von harry_bygraves am 26/05/2013.
harry_bygraves
Mindmap von harry_bygraves, aktualisiert more than 1 year ago
harry_bygraves
Erstellt von harry_bygraves vor mehr als 11 Jahre
59
0

Zusammenfassung der Ressource

Variation in population size
  1. Population size - number of individuals in a population
    1. Population density - the number of individuals per unit area
      1. Population growth - a change in the number of individuals
        1. Population growth rate - the change in number of individuals per unit time
          1. S-shaped population growth curves
            1. the population growth curve of a population colonizing a new habitat in which conditions are intially ideal has an s shape
              1. Phase 1; Slow growth
                1. Phase 2; exponential growth
                  1. Phase 3; decelerating growth
                    1. Phase 4; population stabilizers
                  2. Enviromental factors that limit popualtion size
                    1. Density dependant factors - as the popualtion density increases, density-dependant factors affect a larger proportion of the population. they are usually biotic and include intraspecific competition for space and other resources, availability of food, disease, and preditation
                      1. Density-independant factors - these facotrs affect the same proportion of the population no matter how great its density. they are usually abiotic. the most important are weather and climate
                      Zusammenfassung anzeigen Zusammenfassung ausblenden

                      ähnlicher Inhalt

                      Ecological niche
                      harry_bygraves
                      Investigating populations
                      harry_bygraves
                      Risk management and ethics
                      harry_bygraves
                      Analysing and interpreting data
                      harry_bygraves
                      Populations and Communities
                      harry_bygraves
                      Human populations
                      harry_bygraves
                      Cellular respiration
                      harry_bygraves
                      Population genetics; the Hardy-Weinberg principle
                      harry_bygraves
                      AQA Biology Unit 4
                      Stormageddon
                      Inheritance
                      harry_bygraves
                      Codominance and multiple alleles
                      harry_bygraves