We can analyse the arrows in a food web to identify producers, primary consumers, secondary consumers, and decomposers.
We can analyse the arrows in a food web to identify producers, primary consumers, secondary consumers, and decomposers.
Food webs are models that demonstrate how matter and energy is transferred between producers, consumers, and decomposers as the three groups interact within an ecosystem. Transfers of matter into and out of the physical environment occur at every level. Decomposers recycle nutrients from dead plant or animal matter back to the soil in terrestrial environments or to the water in aquatic environments. The atoms that make up the organisms in an ecosystem are cycled repeatedly between the living and nonliving parts of the ecosystem.
Plant cells have a cell wall in addition to a cell membrane, whereas animal cells have only a cell membrane. Plants use cell walls to provide structure to the plant. Plant cells contain organelles called chloroplasts, while animal cells do not. Chloroplasts allow plants to make the food they need to live using photosynthesis.
All living things are made up of cells, which is the smallest unit that can be said to be alive. An organism may consist of one single cell (unicellular) or many different numbers and types of cells (multicellular).
This short online lesson discusses the planet Jupiter.
This short online lesson discusses the planet Venus.
This short online lesson explores the planet Mercury.
These four short online lessons will cover the following:
This short online tutorial highlights the difference between weather and climate.