Chapter
3
Key Terms
Autolysis................... 47 Golgi body or apparatus....... 47 Plasmalemma.............. 43.
Carotene.................... 51 Granum.................... 51 Polar...................... 44
Cellulose.................... 51 Lamella................... 51 .. Prokaryotic................. 39.
Centrioles................. 49.. Leucoplasts................. 51 Protein synthesis............ 49
Centrosome................ 49. Lysosomes................. 46. Protoplasm.................. 39
Chloroplasts................ 51. Messenger RNA.............. 48 Ribonucleic acid............. 45
Chromatin.................. 45 Micrometers................. 41 Ribosomes.................. 48
Chromoplasts............... 51. Microns..................... 41 Rough (granular) ER.......... 47
Cilia........................ 50 Microtubules............... 50. Smooth (agranular) ER........ 47
Cisternae................... 47 Mitochondrion............... 46 Thylakoid.................. 51
Cristae..................... 46 Nonpolar................... 44 Transcription............... 48.
Cytoplasm.................. 41 Nuclear membrane........... 44 Transfer RNA............... 49.
Deoxyribonucleic acid......... 45 Nucleolus.................. 45. Translation................. 49
Endoplasmic reticulum........ 47 Nucleoplasm............... 40. Tubulin.................... 50
Eukaryotic.................. 39 Nucleus..................... 44 Vacuoles................... 44
Flagella................... 50 Organelles................. 39. Xanthophyll................ 51
Fluid mosaic model........... 43 Plasma membrane........... 43
Introduction
The cell is the basic unit of biologic organization of the
human body. During our lifetime, our bodies are made up
of trillions of cells. Although cells have different func-tions
in the body, they all have certain common struc-tural
properties. All cells are composed of protoplasm, which
is an aqueous colloidal solution of carbohydrates, proteins,
lipids, nucleic acids, and inorganic salts sur-rounded by a
limiting cell membrane. This protoplasm (proto meaning
“first” and plasm meaning “formed”) is predominantly
water with organic compounds in a col-loidal suspension
and inorganic compounds in solution.
These compounds are the building blocks of structures
within the protoplasm called organelles. Some organelles
are common to most cells. Higher cells like those of the
human body are called eukaryotic cells (eu 5 true); cells
that do not have membrane-bound organelles (e.g., bac-
teria) are called prokaryotic cells.
Organelles that are common to all eukaryotic cells are
the nucleus, the mitochondria, the endoplasmic reticulum,
ribosomes, the Golgi apparatus, and lys-osomes. If a cell
has a specialized function that other cells do not have, for
example, movement, the cell will have specialized
organelles. Cells in our bodies that move materials across
their exposed or free surface will