Students examine the Periodic Table and show how periodicity of the physical and chemical properties of the elements relates to atomic structure. As a basis for understanding, students:

Students see patterns in biological, chemical, and physical properties of matter that result from the ability of atoms to form bonds, based on electrostatic forces between electrons and protons, and between atoms and molecules.

Students identify that acids, bases, and salts are three classes of compounds that form ions in water solutions.

Students explain how bonding characteristics of carbon lead to many different molecules with varied sizes, shapes, and chemical properties, providing the biochemical basis of life.

Students analyze atomic nucleus changes by processes that include radioactive decay of naturally occurring and man-made isotopes, nuclear fission and nuclear fusion.

Students conclude waves have characteristic properties that do not depend on the type of wave.

Students recognize energy cannot be created or destroyed, although in many processes energy is transferred to the environment as heat.

Students observe that fundamental life processes of plants and animals depend on a variety of chemical

reactions that are carried out in specialized areas of the organism's cells.

Students formulate that mutation and sexual reproduction lead to genetic variation in a population.

Students recognize that a multicellular organism develops from a single zygote, and its phenotype depends on its genotype, which is established at fertilization.

Students observe that genes are a set of instructions, encoded in the DNA sequence of each organism that

specify the sequence of amino acids in proteins characteristic of that organism. Students examine how the genetic composition of cells can be altered by incorporation of exogenous DNA into the cells.

Students recognize that stability in an ecosystem is a balance between competing effects.

Students discover that the frequency of an allele in a gene pool of a population depends on many factors, and may be stable or unstable over time.

Students connect the concept that evolution is the result of genetic changes that occur in constantly changing environments.

Students conclude that as a result of the coordinated structures and functions of organ systems, the internal

environment of the human body remains relatively stable (homeostatic), despite changes in the outside environment.

Students examine that organisms have a variety of mechanisms to combat disease.

Students correlate how plate tectonics operating over geologic time have changed the patterns of land, sea, and mountains on the Earth's surface.

Students conclude that the energy that enters the Earth system primarily as solar radiation eventually escapes as heat. Students infer that heating of Earth's surface and atmosphere by the sun, drives convection within the atmosphere and oceans, producing winds and ocean currents. Students recognize that climate is the long-term average of a region’s weather and that it depends on many factors.

Students examine how life has changed Earth's atmosphere and how changes in the atmosphere affect conditions for life.

Students recognize that the geology of California underlies the state's wealth of natural resources as well as its natural hazards.

Students assess scientific progress by asking meaningful questions and conducting careful investigations.

Students develop their own questions and perform investigations.

In its effort to explain natural phenomena, scientific concepts must be expressed clearly and properly.