CELL MEMBRANE
• The cell membrane is selectively-permeable( ions and organic molecules), controls the movement of substances in and out of cells.
• It consists of the phospholipid bilayer, consisting of hydrophob
...
CELL MEMBRANE
• The cell membrane is selectively-permeable( ions and organic molecules), controls the movement of substances in and out of cells.
• It consists of the phospholipid bilayer, consisting of hydrophobic tails and hydrophilic heads with embedded proteins, which are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell signaling.
• The plasma membrane also serves as the attachment surface for the extracellular glycocalyx and cell wall and intracellular cytoskeleton
Function
• The cell membrane surrounds the protoplasm of a cell and, in animal cells,
• physically separates the intracellular components from
the extracellular environment.
• anchoring the cytoskeleton to provide shape to the cell
• attaching to the extracellular matrix and other cells to help group cells together to form tissues.
• The barrier is differentially permeable and able to regulate what enters and exits the cell,
• Thus facilitating the transport of materials needed for survival.
• The movement of substances across the membrane can be either passive, occurring without the input of cellular energy,
• active, requiring the cell to expend energy in moving it. The membrane also maintains the cell potential.
A typical animal cell. Within the cytoplasm, the
major organelles and cellular structures include:
(1) nucleolus (9) Mitochondria
(2) nucleus (10) Vacuole
(3) ribosome (11) Cytosol
(4) vesicle (12) Lysosome
(5) rough endoplasmic reticulum (13) Centriole
(6) Golgi apparatus
(7) cytoskeleton
(8) smooth endoplasmic reticulum
• The cytoplasm has three major elements
1. cytosol
2. organelles
3. inclusions
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