Cell Structure and Function: The Molecular Machinery of Life

Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the third of four Science Objects in the Cell Structure and Function SciPack. It explores cells at the molecular level. It is at the molecular level that many of the basic functions of organisms are carried out such as, protein synthesis, extraction of energy from food, and replication. All cells have similar types of complex molecules that are involved in these basic activities of life. These macromolecules include proteins, lipids, carbohydrates and nucleic acids, which interact in a soup, about 2/3 water, surrounded by a membrane that controls what can enter and leave the cell. Proteins act in several ways including enzymes that are responsible for catalyzing chemical actions, receptor molecules in the cell membrane, hormones that travel distances to communicate regulatory processes and structurally as the physical fibers of the cell. The cell’s energy comes from food in the form of sugars or from stored fats (lipids). Lipids are also a critical component in the structure of the cell membrane. The cell membrane in association with carbohydrates and proteins, regulate the flow of water, ions, and other molecules into and out of the cells. Nucleic acids contain instructions for genes that determine structural and chemical processes through protein synthesis.s.


Elementary SchoolMiddle School


Type Science ObjectStock # SCB-CSF.2.1

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