Lecture 1: Introduction to Cell Biology
• Biology is studied at different levels of organization
Time Scale
• [Figure 1-9] How big is a cell and how big are its parts?
• There are important similarities that all cells share; however, there are also important differences among various cell types (for example, animal cells vs. bacterial cells)
• [Figure 3-23] The inside of a cell is loaded (crowded, packed) with molecules including RNA, ribosomes and proteins.
o A cell is already packed, even with these few components; without even considering other organelles and components present in cells, the cell is already crowded; crowding changes the behavior of cellular components
• Many different kinds of cells exist; however, there are just two fundamental types:
o Prokaryotic cells
o Eukaryotic cells ( the focus of BISC 315
• Bacterial cells are prokaryotic.
o Escherichia coli (E. coli) [Figure 1-11]
• Eukaryotic cells are found in organisms other than bacteria. [Figure 1-8a]
o They are characterized by membrane-surrounded organelles. In this class, an organelle is a compartment in a cell that is surrounded by a membrane. Ribosomes are not surrounded by a membrane; therefore, they are not organelles.
o Organelles only occur in eukaryotic cells.
Tools for Cell Biology Research
• Some common tools
• Model Organisms
o See Chapter 1 for related information.
Common Tools
• Microscopy
o Historically major tool
o Until the early 1960’s, this was the primary technique [Figure 1-6]
▪ Eggs are individual cells that are large enough to see; however, most cells are too small to see.
▪ Microscopy is not our ONLY major tool anymore, but it is still very important.
o There is a