Example

• Plasma Membrane

  • Major component is phospholipid
  • Phosphate group interfaces with water inside and outside the cell
  • Lipid "tails" face each other creating a lipid bilayer
  • Layer embedded with proteins, some with carbohydrate components for cellular recognition
• All living organisms are composed of cells. It is the basic structural and functional unit of life
• Transport of Materials into and out of Cells

  1. Diffusion

  2. Facilitated diffusion

  3. Osmosis

  4. Filtration

  5. Active transport(solute pumping)

  6. Bulk transport

  7. Exocytosis

  8. Endocytosis

  9. Phagocytosis

  10. 10. Pinocytosis
• Cytoplasm

  Consists of all the cellular contents between the plasma membranes and the nucleus
• Cell theory


  • 1. Cells are the basic units of life.
  • 2. All organisms are made up of cells
  • 3. Cells arise from other living cells
• Plasma Membrane Function

  • Encloses cell contents, mediates exchanges with the extracellular environment, and plays a role in cellular communication
  • Selectively permeable, permitting some substances to pass more readily than others
• Transport Processes Across The Plasma Membrane

  Membrane transport is the processes by which cells take in or secrete or excrete materials through the selectively permeable cell membrane. Substances move across the plasma membrane by passive processes, which depend on the kinetic energy of molecules or on pressure gradients, and by active processes, which depend on the use of cellular energy (ATP)
• Variations of cells

  Cells vary widely in both shape and size. The shape of a cell depends on its function. In animal cells, cytoskeleton (microtubules and microfilaments) maintain the shape of the cell. Cells also vary in size
• Cytoplasm and organelles are the cellular region between the nuclear and plasma membranes, consisting of the cytosol (fluid cytoplasmic environment) and inclusions (nonliving nutrient stores)
• Cytosol


  • Medium in which many cell metabolic reactions occur, composed of water, solutes, suspended particles, lipid droplets, and glycogen granules
• Cytosol


  Fluid portion of the cytoplasm consisting mostly of water plus dissolved solutes and suspended particles
• Cell division is essential for body growth and repair, occurring during the M phase of the cell cycle
• Meiosis

  Process where one cell divides twice to form four cells with the haploid number of chromosomes, involved in egg and sperm cell formation
• Pinocytoses


  Process of engulfing proteins
• Fertilization of an egg by a sperm restores the diploid number in the fertilized egg
• Organelles


  Specialized structures within a cell that have specific functions
• Summary of Cell Organelles and their Functions

  1. Mitochondria - ATP production

  2. Ribosomes - Synthesis of proteins

  3. Rough endoplasmic reticulum - Protein modification

  4. Smooth endoplasmic reticulum - Synthesizes lipid and steroid molecules

  5. Golgi apparatus - Packages protein secretions

  6. Lysosomes - Sites of intracellular digestion

  7. Peroxisomes - Protect the cell from toxic substances

  8. Microfilaments - Structural support

  9. Microtubules - Structural support and cell movement

  10. Centrioles - Form the mitotic spindle

  11. Nucleus - Control center containing genetic material
• Cell Cycle


  Series of changes a cell goes through from formation until division, including interphase (G1, S, G2) and cell division (mitosis and cytokinesis)
• Mitosis


  Process where one cell divides to form two cells with the diploid number of chromosomes, involving stages like prophase, metaphase, anaphase, and telophase
• Cytoplasm and Organelles

  Cellular region between the nuclear and plasma membranes, consisting of cytosol, inclusions, and cytoplasmic organelles
• Cytoplasm

  All the cellular contents between the plasma membranes and the nucleus
• Nucleus is the largest organelle of a cell and acts as the control center containing genes that control cellular structure and activities