Microscopy

Microscopy

• Electron microscopes use electrons to visualize objects, providing higher resolution than light microscopes.
• Resolution in microscopy refers to the minimum distance between two points that can still be distinguished as separate.
• Electron microscopes have higher resolution than light microscopes due to the shorter wavelength of electrons compared to light.
• Low resolution in a microscope results in a blurry or indistinct image.
• The main difference between Light Microscopy and Electron Microscopy is the type of illumination used: light vs. electrons.

Cell-Cell Connections and Extracellular Matrix

• The extracellular layer in cells serves as a supporting structure, regulates the movement of molecules, and provides mechanical strength.
• The purpose of cell-cell connections is to facilitate communication and adhesion between adjacent cells.
• The main protein fiber found in the extracellular matrix (ECM) is collagen.
• Tight junctions between animal cells function to prevent the leakage of molecules between cells.
• Gap junctions between animal cells allow for the direct exchange of molecules between cells.
• Desmosomes between animal cells function to hold cells together and provide mechanical strength.
• In plant cells, adjacent cells are connected through plasmodesmata.
• Adherens junctions are common in epithelial and muscle tissue.

Functions of Extracellular Matrix

• The extracellular matrix (ECM) provides structural support, regulates cell behavior, and serves as a reservoir for signaling molecules.
• The ECM does not function as a hormone-producing organ.

Note: Some questions had duplicate or similar information, so I've condensed the notes to focus on the key facts and concepts.