Lecture 2/3 Flashcards
What are the levels of organization?
Atomic Molecular Sub-cellular Cellular Tissue Animal Species Ecological Global "Galaxial" Universal
What is a solute?
A substance dissolved in solution
What is a solvent?
The most abundant compound in an area that you are defining
What is solubilize?
To make a substance more soluble.
What is insoluble?
A substance that cannot be dissolved in solution.
What is a hypotonic solution?
solution that has a lower osmotic pressure than another solution (ie the inside of a cell)
What is a hypertonic solution?
A solution that has a higher osmotic pressure than another solution.
(ie the inside of a cell)
What maintains a separation between internal and external environments?
The phosphlipid bilayer
What are integral porteins?
Proteins that are embedded in the phosphlipd by-layer (pumps)
What are Peripheral proteins?
proteins found within the cell that are noncovalently bonded to integral proteins or lipids.
What is the structure of a Phospholipid?
- Polar (hydrophilic) head made of a choline and phosphate group.
- Nonpolar (hydrophobic) tail made of a long fatty acid chain.
Is a phospholipid hydrophobic or philic?
Neither,
It is amphipathic
What are the five functional proteins?
Channels Transporter/carrier Enzyme Receptor Structural protein
What is the function of a channel?
A channel permits simple or quasi-simple diffusion of solutes in aqueous solution, or osmosis of water through a membrane.
What is the function of a transporter/carrier?
Binds noncovalently and reversibly with specific molecules or ions to move across a membrane intact.
What is the function of an enzyme?
Catalyzes a chemical reaction in which covalent bonds are made or broken.
What is the function of a receptor?
A receptor protein binds noncovalently with specific molecules and as a consequence of this binding, initiates a change in membrane permeability.
What is the function of structural proteins?
A protein that is attached to other molecules, to anchor intracelluar elements to the cell membrane.
What are tight junctions and separate junctions?
occlude the intercelluar space between two cells because not only do the cell membranes meet or fuse at such junctions.
What is a desmosome?
A localized spot where the contact between cells is strengthened
What is a Gap junction?
A Gap junction is a localized spot where the cytoplasms of two cells communicate through tiny pores. This communication goes both ways.
What happens to a cell in a hypotonic solution?
It bursts.
Over time, the cell returns to normal volume by……
Regulating internal volume.
What is the purpose of microvili?
To increase surface area for transportation.
How can you pick out a endocrine cell?
They have no ducts, and only releases stuff into the blood system.
When a cell has a lot of mitochondria what does it mean?
They are energy intensive, and important.
Generally in regards to transport.
What are the two routes that a solute can take through a cell?
Transcelluar: Through the cell
Paracelluar: Beside/in between cells
What two membranes must s solute pass through should it take a transcelluar route?
Must cross through both apical and basolateral cell membranes.
What is the primary site on a enzyme called?
The Orthosteric site
What is the secoundary site on an enzyme called?
The allosteric site
What are the reaction steps to create lactic acid? (Lactate dehydrogenase enzyme)
Pyruvic acid +2H -> Lactic acid
Do the fatty acid tails on phospholipids become saturated or unsaturated in cold temperatures?
They become unsaturated, generating more double bonds and increasing membrane fluidity.
What is the key role of an enzyme in a reaction?
To lower the activation energy.
How can you tell if a reaction if exothermic (graph)
IF the products have less energy than the reactents
What are alloszymes?
Enzymes with differing affinity.
What is Affinity?
The General liking of something
How are Km and Affinity related?
Km is inversely related to Km
What is Km?
the Substrate concentration needed for the enzyme catalyzed reaction to proceed at 1/2 of maximum velocity.
What can we infer if the Vmax rises within a reaction?
Then the concentration of the Enzyme has increased in the reaction.
