Populations
Übersicht
Put a few yeast cells in sugar solution and come back in a week: where there were dozens, there are now millions, and then, just as suddenly, the numbers crash. Almost every population, from bacteria to buffalo, follows the same S-shaped story, racing upward and then hitting the limits of its world.
In this lesson you will define population, community and ecosystem, name the factors that drive numbers up and down, and read the four phases of the sigmoid growth curve. You will learn to explain each phase in terms of food, competition, predation and disease, the same limiting factors that decide how many of any species a habitat can hold.
Ziele
- Describe a population as a group of organisms of one species, living in the same area, at the same time
- Describe a community as all of the populations of different species in an ecosystem
- Describe an ecosystem as a unit containing the community of organisms and their environment, interacting together
- Identify and state the factors affecting the rate of population growth for a population of an organism, limited to food supply, competition, predation and disease
- Identify the lag, exponential (log), stationary and death phases in the sigmoid curve of population growth for a population growing in an environment with limited resources
- Interpret graphs and diagrams of population growth
- [Supplement] Explain the factors that lead to each phase in the sigmoid curve of population growth, making reference, where appropriate, to the role of limiting factors
Audiolektion
Diese Lektion in der App anhoren
Mindmap
Dieses Thema ist als Karte dargestellt, damit die Zusammenhange sichtbar werden.
Mindmap in der App offnen
Lernkarten
Schnelles Abfragen der Fakten, die zu diesem Thema gepruft werden.
Diese Karten in der App uben
Lektionshinweis
Vollstaendige Lernnotiz in der Green Bridge App
Holen Sie sich die Green Bridge CBT App auf Handy oder Computer fuer die komplette IGCSE-Bibliothek: fruehere Pruefungen, Bewertungsschemata, Mindmaps, Lernkarten und Audiolektionen.
Unterrichtsbewertung
Herzlichen Glückwunsch zum Abschluss der Lektion über Populations. Jetzt, da Sie die wichtigsten Konzepte und Ideen erkundet haben,
Sie werden auf eine Mischung verschiedener Fragetypen stoßen, darunter Multiple-Choice-Fragen, Kurzantwortfragen und Aufsatzfragen. Jede Frage ist sorgfältig ausgearbeitet, um verschiedene Aspekte Ihres Wissens und Ihrer kritischen Denkfähigkeiten zu bewerten.
Nutzen Sie diesen Bewertungsteil als Gelegenheit, Ihr Verständnis des Themas zu festigen und Bereiche zu identifizieren, in denen Sie möglicherweise zusätzlichen Lernbedarf haben.
- A population is best described as: A. all the living things in an area B. a group of one species in the same area at the same time C. organisms plus their environment D. all the consumers in a food web Answer: B
- Which is NOT a factor affecting the rate of population growth? A. food supply B. predation C. disease D. the colour of the soil Answer: D
- In the sigmoid curve, the phase of most rapid growth is the: A. lag phase B. exponential phase C. stationary phase D. death phase Answer: B
- During the stationary phase of population growth: A. there are no births B. birth rate equals death rate C. death rate is zero D. the population doubles each hour Answer: B
- An ecosystem is: A. one species in an area B. all populations of different species C. a community plus its non-living environment D. only the producers Answer: C
Bearbeiten Sie diese Fragen in der App
Bearbeiten Sie diese Fragen in der App
Empfohlene Bücher
Weiterlernen mit offenen Quellen
-
Lehrbuchabschnitt
Environmental Limits to Population Growth
Explain the characteristics of and differences between exponential and logistic growth patterns
"Biology: Environmental Limits to Population Growth" by OpenStax, OpenStax, Rice University, licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source: https://openstax.org/books/biology/pages/45-3-environmental-limits-to-population-growth. Access for free at https://openstax.org/books/biology/pages/1-introduction
-
Lehrbuchabschnitt
Population Dynamics and Regulation
Give examples of how the carrying capacity of a habitat may change
"Biology: Population Dynamics and Regulation" by OpenStax, OpenStax, Rice University, licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source: https://openstax.org/books/biology/pages/45-4-population-dynamics-and-regulation. Access for free at https://openstax.org/books/biology/pages/1-introduction
Von anderen Organisationen unter offenen Lizenzen veröffentlicht und wie gewünscht genannt. Links öffnen deren Websites.
Übungsklausuren üben
Möchten Sie Übungsklausuren zu Populations üben? Laden Sie die Green Bridge CBT App herunter, um Übungsklausuren und vollständige Prüfungssimulationen zu diesem Thema zu erhalten.
Lade die App im Google Playstore herunter.
Alles, was du brauchst, um in JAMB, WAEC & NECO zu glänzen.
