Interactions of ecosystems Flashcards
(53 cards)
What is a habitat?
An area which an organism lives, including all the biotic factors and abiotic factors that affect it.
Biotic factors include living elements like plants and animals, while abiotic factors include non-living elements like climate and soil.
What is a niche?
A full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions.
Includes food acquisition methods and behavioral patterns.
What occurs when two species use the same resources?
Conditions of competition.
This can lead to competitive exclusion or resource partitioning.
What is competitive exclusion?
It keeps two species from occupying the same niche, meaning NO TWO SPECIES OCCUPY THE SAME NICHE.
Leads to three possible outcomes.
What are the three outcomes of competitive exclusion?
- One species is better suited and the other is pushed out or becomes extinct
- The niche is divided
- The two species further diverge
Examples include the North American Grey Squirrel and the European Red Squirrel.
What are ecological equivalents?
Species that occupy similar niches but live in different geographical regions.
Define intraspecific competition.
Competition between two organisms of the same species for a resource.
Define interspecific competition.
Competition between two different species fighting over the same resource.
What is predation?
When one organism captures and eats another.
What are the three major types of symbiotic relationships?
- Mutualism: both organisms benefit
- Commensalism: one organism benefits, the other is unharmed
- Parasitism: one organism benefits, and the other is harmed
What are ectoparasites?
Parasites that live on the outside of the body, such as leeches.
What are endoparasites?
Parasites that live inside the body, such as hookworm.
What is population density?
A measure of the number of individuals living in a defined space.
How can scientists calculate population density?
Using the formula: # of individuals = population density / Area (units)².
What does geographic dispersion refer to?
How individuals in a population are spaced.
What are the three types of population dispersion?
- Clumped
- Uniform
- Random
Examples include schools of fish for clumped, certain birds for uniform, and dandelions for random.
Why is the California red-legged frog a threatened species despite laying 200 to 5000 eggs?
Predators can eat their eggs.
What is a survivorship curve?
A diagram showing the number of surviving members over time from a measured set of births.
What information do survivorship curves provide?
They give information about the life history of a species by measuring the number of offspring born and following them until they die.
What are the three types of survivorship curves?
- Type I: low level of infant death, common in large mammals and humans
- Type II: equal survivorship rate at all life stages, common in birds and reptiles
- Type III: very high birth rate and high infant mortality, common in invertebrates and plants
What is the difference between habitat and niche?
A habitat is where an organism lives, while a niche encompasses all the biotic and abiotic factors in that habitat and how the organism utilizes them.
What is commensalism?
A symbiotic relationship in which only one species benefits and the other is neither harmed nor benefited.
What type of symbiotic relationship exists between a flower and the insect that feeds on its nectar?
Mutualism
Mutualism is a type of interaction where both species benefit from the relationship.
What is the density of the student population in Mr. Montejoano’s classroom?
0.10 students/m2
Density is calculated as the number of individuals divided by the area.
