Unit 8: Ecology

Phototropism

________ refers to the way plants respond to sunlight- for example, bending toward light.

Habituation

________ is another form of learning.

Endotherms

________ are animals that generate their own body heat through metabolism.

Toxins

________ in an ecosystem are concentrated and more dangerous for animals further up the pyramid.

Plants

________ flower in response to changes in the amount of daylight and darkness they receive.

Ectotherms

________ lack an internal mechanism to control body temperature.

Commensalism

________- in which one organism lives off another with no harm to the host organism (for example, the remora)

Exponential growth

________ occurs very quickly, resulting in a J- shaped curve.

Thigmotropism

________ refers to the way plants respond to touch.

food chain

In a(n) ________, only about 10 percent of energy is transferred from one level to the next- this is the 10 % rule.

Biosphere

________: The entire part of the Earth where living things exist.

Parasitism

________- in which the organism actually harms its host.

Territoriality

________ is a common behavior when food and nesting sites are in short supply.

Instinct

________ is an inborn, unlearned behavior.

Lichens

________ are considered pioneer organisms.

chemical signals

Pheromones, are ________ between members of the same species that stimulate olfactory receptors and ultimately affect behavior.

Dominance hierarchies

________ (pecking orders) occur when members in a group have established which members are the most dominant.

Mutualism

________- in which both organisms win (for example, the lichen components)

Net productivity

________ measures organic materials that are left over after photosynthetic organisms have taken care of their own cellular energy needs.

tropism

A(n) ________ is a turning in response to a stimulus.

behavior brought

Learning refers to a change in a(n) ________ about by an experience.

maximum number of individuals

Carrying capacity- the ________ of a species that a habitat can support.

energy flow

The ________, biomass, and numbers of members within an ecosystem can be represented in an ecological pyramid.

Altruistic behavior

________ is defined as unselfish behavior that benefits another organism in the group at the individuals expense because it advances the genes of the group.

Population growth

________ can be represented as the number of births minus the number of deaths divided by the size of the population.

Exponential growth

________ occurs when a population is in an ideal environment.

Biosphere

The entire part of the Earth where living things exist

Ecosystem

The interaction of living and nonliving things

r = (births

deaths)/N (r is the reproductive rate, and N is the population size.)