Concept 2.1: Matter consists of chemical elements in pure form and in combinations

Flashcards from Concept 2.1 of Pearson's Campbell Biology, Twelfth Edition.

Compound

Two or more elements in a fixed ratio joined by bonds which determine its properties

Protons

The positive subatomic particles in an atom that determine an atom’s identity

Electrons

The negative subatomic particles in an atom that determine an atom’s ability to form bonds

Matter

Anything that takes up space and has mass; this is made up of elements

Element

A substance that cannot be bropken down to other substances by chemical reactions

Emergent properties

Characteristics of a compound that are different from those of its elements

Essential elements

The 20 to 25% of the 92 natural elements required for life

• Crabon, hydrogen, oxygen, and nitrogen make up 96% of living matter

• The remaining 4% consists of calcium, phosphorus, potassium, and sulfur

Trace elements

Elements required by an organism in only minute quantities

Toxicity

Some elements can be this; certain species can become adapted to environments containing these elements

• Some plant communities are adapted to sepentine