Notes for Bilingual Biology class

2. ENVIRONMENTAL FACTORS AND
ADAPTATION TO THE ENVIRONMENT
ECOLOGICAL FACTORS:
Characteristics of the environment that affect living things.
They can be abiotic or biotic.
Limiting factor: is the quantity of ecological factors that is above or below the point at
which an organism cannot develop properly.
Adaptation: is the evolution of organisms so that they are able to survive in a specific
environment.
It can be:
morphological
physiological
behavioural adaptation

3. ADAPTATION TO WATER SCARCITY
ADAPTATION TO TEMPERATURE CHANGES

4. ADAPTATION TO SUNLIGHT
ADAPTATION TO VARYING SALT CONCENTRATION

5. ADAPTATION TO LACK OF OXYGEN
Increase in red blood cells and haemoglobin
Increase in lung capacity
ADAPTATION TO LACK OF FOOD
Storing energy reserves in their body
Storing food in hidden places
Migrating to find food

6. POPULATIONS
A population is a group of organisms of the same species that inhabit the same territory and
that can reproduce together.
TYPES OF POPULATIONS
TYPE CHARACTERISTICS EXAMPLE
Invertebrate
colonies
Individuals are connected
to each other.
Asexual reproduction
Family groups Pair of animals whose
offspring stay together
with the family unit
Caste system of
social insects
Individuals come from
one mother.
They have different roles
in the community
Social groups Individuals tend to live
together and support each
other mutually.

7. POPULATION DYNAMICS
Biotic potential: (r) is the maximun reproductive potential of a population, which is
the difference between the birth rate and the death rate
Population growth:
Decreasing population
Increasing population
Population that will increase
Population growth strategies:
R-strategists: Desert plants. They use environmental resources to produce numerous populations.
K-strtaegists: birds and mammals. They maintain a stable populations with controlled growth

8. COMMUNITIES
A community is a set of popualtions of different organisms taht live together in the
same geographical area within a particular habitat.
Diversity is the biological variability among and between species in a community, as well as
the diversity between communities and ecosystems themselves.
DYNAMICS OF COMMUNITIES
Ecological succession is the sequential order in which plant communities and the animal
species associated with them, change over time.
We can distinguish:
Primary succession
Secondary succession
RELATIONSHIPS WITHIN COMMUNITIES
Predation
Competition
Parasitarism
Social parasitarism
Commensalism
Symbiosis
Inquilinism
Mutualism