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The human cell - Coggle Diagram

- - - - secretory vesicles
        
        transports proteins to cell membrane for secretion
      - storage vesicles
        
        stores contents in the cell
        
        ex: lysosomes
  - - - function to make proteins from amino acids using DNA's instructions
    - - fixed ribosomes
        
        are attached to the ER
      - free ribosomes
        
        float in cytoplasm
        
        can form chains called polyribosomes
  - - - covered in ribosomes
      - makes proteins
        
        these proteins are packaged in vesicles to be delivered to the Golgi
    - - does not have ribosomes attached
      - makes fatty acids and lipids
    - - regulates movements of substances into and out of the cell
        (semipermeable)
      - detects chemical signals from other cells
      - forms physical links with adjacent cells
    - - cylindrical bundles of microtubules for directing DNA movement during cell division
    - - contains DNA used to produce RNA in the ribosomes
- - - - ions
      - glucose
  - - - O2
      - CO2
      - steroid hormones
  - - - have hydrophobic tail
        
        phosphate head
      - have hydrophilic head
        
        lipid tail
        
        faces away from the aqueous, extracell and intracellular solution into the cell membrane
    - - found in the non-polar lipid layer
      - makes membrane impermeable to water soluble molecules and fluid at diff temperatures
    - - attached to intracellular or extracellular surface of the membrane
        
        catalyzes rxns
    - - found with extracellular membrane proteins/lipids
      - forms the glycocalyx (protective layer )
        
        helps with imm. response
        
        helps with recognition of other cell
    - - act as gates or channels to let certain substances across the membrane
    - - found on the inside of the cell membrane
      - strengthens the membrane
      - anchor cell organs on the intracellular side
  - - - allow water-soluble ions to pass
    - - transport molecules across the membrane
    - - help with reaction of molecule breakdown
    - - help with a imm. response
    - - where chemical hormones and neurotransmitters attach
    - - diffusion through protein channels for water and water-soluble molecules
      - facilitated diffusion
      - diffusion of fat soluble molecules
      - active transport
      - endocytosis/pinocytosis/phagocytosis
- - - - caused by the accumulation of anions inside the cell and cations outside the cell
        
        results in a electric potential difference across the membrane even in a resting state (found in all cells in the body)
        
        -70 mV
    - - electrochemical equilibrium
        
        the zero net movement of substances
        
        causes by electrical and concentration gradient being equal in magnitude but opposite in direction
      - defined as the electrical potential needed to be applied inside the cell to stop ions from moving down their concentration gradient
        
        Na+
        
        +60 mV
        
        voltage required to keep each ion from moving down concentration gradient
        
        K+
        
        -90 mV
        
        Cl-
        
        -70 mV
  - - - makes the inside more negative, contributing to the resting membrane potential
        
        this makes it an electrogenic pump, pumping ions against the concentration gradient using ATP
        
        active transport
      - works to maintain the concentration of these ions
        
        maintaining the concentration gradient ensures the cell does not burst by causing osmosis out of the cell
- - - - high to low concentration is called the chemical concentration gradient
        
        movement continues until there is no more concentration gradient and net movement is zero
    - - this is the electrical gradient
        
        charged ions move in both their electrical and chemical gradient
        
        when the movement of ions depends on the net of the strength of the two gradients
        
        when they are equal but opposite in direction, molecules stop moving
        
        electrochemical equilibrium
    - - can directly diffuse through the membrane
        
        not stopped by the hydrophobic fatty acid chains
    - - diffuses using special protein channels or pores
        
        each pore/channel has specificity for a type of ion
    - - charge of the molecule
        
        opposite charge on the ion and channels pulls the ion through the channel
      - greater electrochemical gradient
        
        causes higher movement through channels
      - size of protein channel (usually 0.8 nm)
        
        bigger molecules cannot diffuse through
      - number of channels in the membrane
        
        more channels available can transport more ions
    - - how large water soluble molecules pass through
      - requires attachment to specific protein carriers on the membrane
        
        causes conformational change in the protein
        
        causes opening for the molecule to pass through
        
        can also rotate the molecule to the inner surface where it is released
      - some important stuff
        
        does not require ATP
        
        powered by the concentration gradient
        
        transport rate is limited by number of available proteins
        
        causes system to become saturated and cannot go any faster
        
        saturation can also occur when the speed conformational change occurs is limited
        
        shows chemical specificity
        
        can be competitively inhibited
    - - can be competitively inhibited
      - can be saturated
      - shows chemical specificity
      - uses ATP to transport molecules against concentration gradient
        (low to high)
    - - requires special pores to diffuse across the hydrophobic portion of the membrane
      - water volume is usually constant in a cell
        
        osmosis is when a concentration difference with water occurs (movement of H2O down its concentration gradient)
        
        water molecules goes to where the solute concentration is high
      - factors affecting osmosis
        
        concentration gradient of the solutes
        
        pressure gradient across the cell membrane
        
        the permeability of the membrane to solutes in interstitial and intracellular space
      - units of osmosis
        
        osmole
        
        unit used to describe number of osmotically active particles (Na+, Cl-, K+, etc.)
        
        osmoles/kg of water
        
        osmoles/L of solution
      - tonicity
        
        the ability of a solution to cause osmosis in a biological cell membrane
        
        fluid in human cells is ~ 300mOsm/kg water
        
        hypotonic
        
        solution has lower concentration compared to cell
        
        causes osmosis into the cell
        
        causes cell to swell
        
        hypertonic
        
        solution has higher concentration compared to cell
        
        cause osmosis out of cell
        
        causes cell to shrink
        
        isotonic
        
        cell and solution are same concentration
        
        no change