Biology Semester 1 Final Review Guide KEY

Primary Consumer

Organisms that eat primary producers (plants).

Tertiary Consumer

Organisms that eat secondary consumers.

Apex Predator

The top predator in a food chain that has no natural enemies.

Decomposer

Organisms that break down dead material and recycle nutrients.

Ecosystem

A community of living organisms interacting with their environment.

Niche Partitioning

Dividing resources among species to reduce competition.

Herbivore

Organisms that primarily eat plants.

Carnivore

Organisms that primarily eat other animals.

Secondary Consumer

Organisms that eat primary consumers.

Habitat

A place where an organism lives.

Carrying Capacity

The number of organisms an ecosystem can sustainably support.

Biotic Factor

Living parts of the ecosystem such as frogs and trees.

Abiotic Factor

Non-living parts of the ecosystem such as rainfall, temperature.

Trophic Level

Feeding level in an ecosystem or food web.

Keystone Species

Species that has an extremely large impact on the ecosystem.

Stomata

Opening on the bottom of a leaf used for gas exchange.

Chloroplast

Organelle in a plant responsible for absorbing the sun's energy.

Photosynthesis

Process that uses sunlight to convert CO2 and water into glucose and O2.

Cellular Respiration

Process that breaks down food (glucose) to make cellular energy (ATP).

Niche

Role an organism has in an ecosystem; its 'job'.

Light Reactions

First stage of photosynthesis where sunlight is absorbed to produce ATP and NADPH.

Calvin Cycle

Second stage of photosynthesis where CO2 is fixed into glucose using ATP and NADPH.

Chlorophyll

Green pigment in plants that absorbs light energy for photosynthesis.

Fermentation

Process to generate energy without oxygen, converting glucose into alcohol or lactic acid.

What is Niche Partitioning?

The process by which different species exploit different resources to reduce competition.

Purpose of Niche Partitioning

To allow coexistence of species in a habitat by minimizing direct competition.

Examples of Niche Partitioning

Birds feeding at different heights in the same tree.

Temporal Partitioning

Using the same resource at different times to avoid competition.

Spatial Partitioning

Occupying different habitats or niches to reduce overlap.

Character Displacement

Changes in species' traits that reduce competition for resources.

Interspecific Competition

Competition between different species for the same resources.

Resource Availability

The distribution of resources that influences niche partitioning.

Niche Differentiation Effects

Can lead to increased species diversity in ecosystems.

Role of Predators in Niche Partitioning

They can influence how resources are partitioned among prey species.