BIO 110 CHAP 5.txt

• Cell membrane is mosaic, a mixed composition of mostly phospholipids. The fluid part of the model refers to the behavior of phospholipids in membranes.
• The phospholipids drift sideways, spin on their axis and their tails wiggle.

• The difference reflect their functions in the cell
• The two surfaces of the bilayer are different
• Different kinds of cells have different kinds of membrane phospholipids

• While some proteins stay put locked in place by the cytoskeleton (those clustered as rigid pores), most proteins in bacterial and eukaryotic cell membranes drift around very quickly
• Archaeans do not build their phospholipids with fatty acids and their bilayers are more rigid.

• Integral membrane proteins – permanently attached to a lipid bilayer
• Peripheral membrane proteins temporarily attach to one of the bilayer’s surfaces by way of interactions with lipids or other proteins

• Adhesion Protein
• Enzyme
• Receptor Protein
• Recognition Protein
• Passive Transporter
• Active Transporter

• Function – attachment of cells to one another and to extracellular matrix
• Occurs only on plasma membranes
• Attachment – Integral
• Examples:
• -Integrins receptors that mediate cell attachment, migration, differentiation, division and survival
• -Cadherins part of adhering junctions between cells
• -Selections bind glycoproteins on the surface o cells that function in immunity

• Function - Speeds a specific reaction
• Attachment – Integral or peripheral
• Example:
• Monoamine oxidase catalyzes a hydrolysis reaction that removes an ammonia group from amino acids.

• Function - Binding signaling molecules (receives signals)
• Binding causes a change in the cell activity
• Attachment – Integral or peripheral
• Example:
• B cell – Protein made only by white blood cells vital for immune response

• Function – identifier of cell type, individual, or species
• Attachment – Integral
• Example:
• MHC molecule allows white blood cells to identify a cell as nonself or self to trigger immune response.

• Function – transport of molecules
• Does not require energy
• Attachment - Integral
• Examples:
• Glucose transporter
• Aquaporin – open channel water transporter

• Function – transport of molecules
• Uses energy to pump substances across the membrane
• Attachment – Integral
• Examples:
• Calcium pump – Uses ATP to pump calcium ions across a membrane
• ATP synthase – Uses ATP to pump hydrogen ions across a membrane

• Diffusion
• Osmosis
• Passive Transport (facilitated diffusion)
• Active Transport
• Vesicular Transport (endocytosis/exocytosis)

• The movement of particles from area of high concentration to an area of low concentration
• Spontaneous – Happens in nature (needs not assistance)
• Gas and water and small ions
• Continues until equilibrium

• The movement of particles from area of high concentration to an area of low concentration with the assistance of a protein
• Channels (no interactions) or gates (interact open and close)

The movement of particles from low to high concentration with the assistance of protein and energy (ATP)

Moves two substances at the same time nearly all of the cells in your body have these pumps

• Uses vesicles to transport items
• Exocytosis vesicles transport items to the PM fuses to expels the content of the Vesticle from the cell
• Endocytosis (Bulk Flow / Receptor)

Nature move and separation from high to low

Name for the movement of water

Relative concentration of solutes in two fluids that are separated by a selectively permeable membrane

• Hypotonic
• Hypertonic
• Isotonic

Fluid with a lower concentration of solutes in comparison to another

Fluid with a higher concentration of solutes in comparison to another

Fluids that has the same over all concentration of solute

Water always move toward the higher concentration of solute

Pressure that fluid exerts on cell wall due to swelling from water in a hypotonic situation

The capacity to do work

Energy is neither created nor destroyed.

The tendency for entropy to increase

Measure of how much the energy of a particular system has become dispersed

Equal amount of mass on both sides of a reaction

• – subscript denotes number of atoms
• - Coefficient denotes the number of molecules

Less free energy in the reactants than the products

More free energy in the reactants that the products

Amount of energy that is available to do work

The minimum amount of energy required to get a reaction started

Catalysts that speed up reactions

When substrates reach their breaking point and the reaction continues to product

Substrate and enzyme come together and fit exactly (old model)

The bonding of the enzyme and substrates improves the fit of the actives site and the substrate over time

Activities work in an organized manner

• Liner
• Cyclic
• Branched

Products from a substrate enzyme reaction that go to other reactions.