Plasma Membrane
Plasma Membrane - Related Videos
12:28
Imaging Plasma Membrane Deformations With pTIRFM
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Cited by 11 •
2014
Polarization-based Total Internal Reflection Fluorescence Microscopy (pTIRFM) enables real-time detection of cell membrane dynamics. This article describes the implementation of pTIRFM for the study of membrane remodeling during regulated exocytosis. The technique is generalizable to other processes in cell biology that directly or indirectly involve changes in membrane shape.
01:22
Enlargement of the Plasma Membrane
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2023
Cell division and enlargement are processes that require precise control. The control ensures that cell division cannot proceed unless the cell has grown to a specific size. A spherical, dividing cell requires an approximately 1.6X increase in its surface area to double its volume. The secretory pathway also has a significant role in cell membrane enlargement. Secretory vesicles that bud off from the Golgi apparatus and later fuse with the plasma membrane during exocytosis are a major source of...
01:27
Plasma Membrane in Bacteria and Archaea
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2025
The plasma membrane is an essential cellular structure responsible for maintaining cellular integrity and regulating the selective transport of molecules. While bacteria and archaea share the fundamental function of plasma membranes, their structural and molecular differences reflect adaptations to distinct ecological and physiological challenges.Bacterial Plasma MembranesBacterial plasma membranes are predominantly composed of phospholipids with fatty acid chains ester-linked to a glycerol...
05:39
Quantitative Measurement of GLUT4 Translocation to the Plasma Membrane by Flow Cytometry
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Cited by 20 •
2010
This protocol describes a rapid technique to quantify the translocation of GLUT4 from the cytoplasm to the plasma membrane of cells by flow cytometry.
12:48
Measuring Near Plasma Membrane and Global Intracellular Calcium Dynamics in Astrocytes
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Cited by 16 •
2009
We describe how to measure near membrane and global intracellular calcium dynamics in cultured astrocytes using total internal reflection and epifluorescence microscopy.
FAQs
Selective permeability arises from the membrane’s phospholipid bilayer and its embedded proteins. The bilayer’s hydrophobic interior restricts many substances, while specific membrane proteins regulate the passage of selected molecules. This arrangement allows the cell to control which materials enter or leave rather than permitting unrestricted exchange with the external environment.
Transport can follow concentration gradients through diffusion, osmosis, or facilitated transport, or it can require cellular energy through active transport. The key distinction is whether movement proceeds according to an existing concentration difference or requires energy to support the cell’s transport needs. These alternatives help maintain internal conditions while enabling nutrient acquisition and waste removal.
Membrane proteins provide routes for transport and contribute to signaling, adhesion, and recognition. Cholesterol is another major membrane component, while carbohydrates are also associated with the membrane structure. Together with phospholipids, these components give the boundary both physical organization and biological functions that allow cells to interact with their surroundings and coordinate activities.
Concentration gradients provide the directional basis for diffusion, osmosis, and facilitated transport. Molecules move in relation to differences in concentration, while the membrane’s selective properties determine which substances can cross directly or require protein assistance. Examining these movements helps explain how cells exchange materials without treating all substances as equally permeable.
Analyzing transport across the plasma membrane can show how a cell obtains nutrients, removes waste, and preserves the conditions required for life. Comparing diffusion, osmosis, facilitated transport, and active transport reveals whether movement follows concentration differences or depends on cellular energy. These observations connect membrane behavior with cellular homeostasis and survival.
Membrane proteins participate in signaling, allowing cells to detect and respond to changes in their surroundings. Membrane carbohydrates contribute to recognition, while proteins also support adhesion between cells or interactions with their environment. Studying these functions helps biology explain how cells coordinate responses, maintain organization, and adjust their internal conditions as external conditions change.