Quiz Flashcards
J-shaped pattern that indicates that there is a steady positive growth rate.
Exponential model
A small growth seen in the first part
Lag phase
a model that describes limited population growth, often due to limited resources
Logistic model
Maximum population size that the environment can sustain
Carrying capacity
Influenced by the population, and mostly biotic.
DENSITY-DEPENDENT FACTOR
when habitat is overcrowded, organisms compete for food, water, space, sunlight and other essentials.
Competition
Were population is controlled
Predation
parasite living in or another organisms consequently harms the host.
Parasitism
diseases harm organisms in a population by causing death or preventing the species from reproducing.
Disease
Not influenced by the population
DENSITY INDEPENDENT FACTOR
4 biotic structure of independent factor
- Unusual weather conditions
- Natural disaster
- Seasonal cycle
- Certain human activities such us damming rivers, clear cutting forests, and indiscriminate or uncontrolled hunting and farming.
population of a given species is part of a bigger group.
Community
number of different species represented in a biological community.
Species richness
where the largest number of species richness can be found.
Tropical rainforest
refers to how common or rare the species in the area.
Relative abundance
members of the same species compete for limited resources.
Intraspecific competition
members of different species compete for a shared resources.
Interspecific competition
Changes the physical and the biological structures of a community.
Disturbance
Causes of disturbance
Natural disasters or human activities
Advantage of disturbance
Create opportunities for new species to thrive and create a new community.
Examples of disturbances
- volcanic eruptions
- tsunamis
- intense forest fires
The gradual and sequential regrowth of a community.
Ecological Succession
the community is established from an area that does not have any topsoil.
Primary Succession
The species that predominate at the early stages
Pioneer species
This happens after a disturbance is experienced by a community
Secondary Succession
Takes shorter time to finish
Secondary Succession
Takes hundreds or millions of years to finish.
Primary Succession
major stable community which is the final stage of ecological succession.
Climax community
How many years does Humans have inhabited Earth?
More than 500 million
How many years does Humans have inhabited Earth?
More than 500 million
About how many years ago does human population growth that is very slow.
10 000 to 20 000 years ago
What kind of group does our ancestors lived in and how do they obtained food?
Small nodamic groups
By hunting and gathering
the increase in world population was three times greater than during the entire previous history of humanity.
Between 1900 and 2000
How many years does it take to get an increase from 1.5 to 6.1 billion
100 years
How many years ago were there are less than one billion humans living on the earth.
200 years ago
according to UN calculations, how many of us are today now
7 billion
Global human population growth amounts to around ____
83 million annually, or 1.1% per year.
It is expected to keep growing, and estimates have put the total population at ___ by mid-2030, ___ by mid-2050 and ___ by 2100.
- 6 billion
- 8 billion
- 2 billion
