Standard LS.2
Cell Structure and Division

Standard LS.2
The student will investigate and understand that all living things are composed of cells. Key concepts include
a) cell structure and organelles (cell membrane, cell wall, cytoplasm, vacuole, mitochondrion, endoplasmic reticulum, nucleus, and chloroplast);
b) similarities and differences between plant and animal cells;
c) development of cell theory; and
d) cell division (mitosis and meiosis).


The cell theory includes the following components: all living things are composed of cells, cells are the smallest unit (structure) of living things that can perform the processes (functions) necessary for life, living cells come only from other living cells.

The development of the cell theory can be attributed to the major discoveries of many notable scientists. The development of the cell theory has been dependent upon improvements in the microscope and microscopic techniques throughout the last four centuries.

Continuing advances in microscopes and instrumentation have increased the understanding of cell organelles and their functions. The structure of a cell organelle reflects the job or function carried out by that organelle.
Division of labor within a cell is essential to the overall successful function of the cell.

Many of these organelles can be observed with a compound light microscope.

Similarities and differences in plants and animals are evident at the cellular level. Plant and animal cells contain some of the same organelles and some that differ.

Cells go through a life cycle known as the cell cycle. The phases of the cell cycle are interphase, mitosis, and cytokinesis. (Although it is appropriate for students at this level to learn to recognize the stages of the cell cycle, an exploration of the individual stages of meiosis may be reserved for high school Biology.)
describe and sequence the major points in the development of the cell theory.

identify the three components of the cell theory.

distinguish among the following: cell membrane, cytoplasm, nucleus, cell wall, vacuole, mitochondrion, endoplasmic reticulum, and chloroplast.
correlate the structures of cell organelles with their jobs and analyze how organelles perform particular jobs.

compare and contrast examples of plant and animal cells, using the light microscope and images obtained from microscopes.

differentiate between mitosis and meiosis.