Question | Answer |
Bond | Atoms are held together by bonds |
Covalent bond | Bonds created by tow atoms that share one or more pairs of electrons |
Ionic bond | A bond btwn ions attracted to each other by opposite charge |
Hydrogen bond | weak attractive forces btwn hydrogens and other atoms, esp. O and N |
Van der Waals forces | Weak attractive force that occurs btwn two polar molecules or a polar molecule and an ion |
Ion | An atom with a net positive or negative charge due to gain or loss of one or more electrons |
Cation | + charged ion |
Anion | - charged ion |
Polarity of a cell | Cells restrict certain membrane proteins to particular regions, thereby creating cell with different funxs in different areas |
Polar molecule | Molecules that develop regions of partial positive and negative charge when one or more atoms in the molecule have a strong attraction for ELECTRONs |
Nonpolar molecule | A molecule whose electrons are distributed so evenly that there are no regions of partial positive or negative charge |
Hydrophilic | Water LOVING |
Hydrophobic | Water HATING |
pH | The concentration of H+ ions in a soln and it measures acidity in that soln; measures influence of the forces and shape |
Changes in acidity | Can alter Hydrogen bonding and van der Waals forces altering shape causing lessened efficiency of the cell; maintaining shape in important for normal funx and activity levels8888888888 |
Buffer | resists change in pH |
Optimal pH | 7-7.6; anything out of this range leads towards death
0 = Acid (Strong Acid)
14 = Base (Weak Acid) |
Biomolecules (4) | Carbohydrates
Lipids
Proteins
Nucleotides
-All used as E and used structurally
-Most exist as polymers; long units built from a basic building block |
Carbohydrates | building blocks = monosaccharides (glucose)
disaccharides (glucose + fructose = sucrose) |
How do plants store glucose? | As starch & Cellulose (long polymer) |
How do animals store glucose? | As glycogen (long polymer) |
Lipids | Made from fatty acids + glycerol; tri, di, & monoglycerides |
What is the storage form of lipids in animals? | Triglyceride |
Proteins | Do the most work in a cell; BB's are Amino Acids; 20+ Amino Acids are a protein; peptide or polypeptide 2-20 amino acids. |
Nucleotides | signaling molecules assembled from RNA & DNA; compd's-polymers of nucleotide |
Actions of soluble proteins | ENZYMES; MEMBRANE TRANSPORTERS activley pushing things in and out of cell; SIGNAL MOLECULES; RECEPTORS; BINDING PROTEINS binding selves to environment; REGULATORY PROTEINS regulating internal processes; Immune activities as IMMUNOGLOBULINS |
Protein binding | Exhibits specificity, affinity, competition and saturation |
Ligund | any molecule tht binds to another molecule |
Substrate | A ligund that binds to an enzyme or membranne transporter |
Specificity | Some mols bind to it but others do not |
Affinity | Tightens/strengthens binding; diff affinities of binding; Hemoglobin has a higher affinity for CO2 that O2 |
Competition | Two substrated that compete for a binding site, reducung the effectiveness of both |
Saturation | Limited number of transporters, receptors and when all are used it creates limited connectivity |
Agonists | Diff ligunds that bind to the same protein and ACTIVATE it |
Antagonists | Ligunds that bind to a protein and BLOCK its function |
Factors that affect protein function | Isoforms, modulators |
Isoforms | Variations made by changing an amino acid in a protein, changing its function with a MEASURABLE EFFECT Ex. Embryonic and Adult Hemoglobin-both funx by binding to O but diff affinityf; Embryonic is higher to get O2 from Mom |
Modulators | Change activity, shape, adn behavior of a protein when temp or pH changes too much |
Competitive inhibitor | Blocks activity; like an irreversible inhibitor |
Irreversible inhibitor | toxins, botox that irreversibly binds to block activity |
Allosteric modulator | A molecule that binds to a receptor NOT at an active site has modualted activity Ex. GABA may inhibit response at target neuron so increase in activity. (?) |
Covalent modulator | Can target specific proteins quickly by attaching a protein to a phosphate (PHOSPHORALATION) and detatch a phospate (DEPHOSPHORALATION) |
Phosphoralation | ADD a phosphate; turn ON; ACTIVATES a protein |
Dephosphoralation | DETATCH a phosphate; Turn OFF; Deactivate a protein |
E in biological systems | -E is used to peroform work; can be either kinetic or potential; can be converted from one form to another; thermodynamics |
Potential Energy | Greatest potential E is at top of a roller coaster |
Kinetic Energy | Released on the way down a roller coaster |
Exergonic reactions | Energy RELEASED during CHEMICAL reactions; Products at LOWER E than the substrates |
Endergonic reactions | Energy is UTILIZED during CHEMICAL reactions; Product has HIGHER E level than the subtrates |
Exergonic and Endergonic reactions can be coupled | Combining two amino acids to make a peptide; Products have higher E by coupling w/an exergonic rxn (ATP) |
Most reactions need an Activation Energy | Ex. Paper is held together by covalent bonds, if burned the ashes hold lower E. Released E as heat doesn't happen onits own b/c its stable and needs Activation E (reaching 450 degrees w/the help of a match) otherwise it will stay in its potential state. |
Enzymes | A+B+enzyme = C+D+enzyme; enzymes lower the Activation E of reactions to allow a rxn to happen that is aventatious for us; Reaction rates are variable |
Metabolism | catabolism, anabolism |
Catabolism | rxns PRODUCE E via breakdown of large biomolecules into their own building blocks |
Anabolism | rxns USE E to produce large biomolecules; combining large molecules to build larger ones |
How is metabolism measured? | Can measure heat released or produced and indirectly the amt of O2 being consumed in kCAls= E content in food= heat released by burning |
Control of Metabolism | Controlling enzyme concentrations, ,modulation of enzymatic activity, reversible rxns, isolation of enzymes, changing ratio of ATP:ADP |
Controlling enzyme concentrations | turning on/off w/ gene activity; most enzymatic rxns have one irriversible direction; some are reversible |
Reversible rxns using ONE enzyme for both directions | RARE |
Reversible rxn requiring TWO enzymes | ONLY LIVER can reverse a rxn |
Irreversible rxn lacks the enzyme for the reverse rxn | ALL CELLS i body can do this; |
Isolation of enzyme | seperate and control rxns Ex. lysosome breaks down stuff |
Shift ratio of ATP:ADP | Less E to slow down metabolism or increase E to increase metabolism |
ATP production from glucose | glycolosis, citric acid cycle, electron transpot chain |
Glycolosis | Breaking down glucose from ATP; IN CYTOPLASM
Breaks down glucose to 2-3 Carbon pyruvate to produce 2 ATP; glycolosis is anerobic (doesn't require O2) |
Nervous sytem and Brain | ONLY USE GLUCOSE for ATP |
ALL other systems | Can breakdown biomolecules for ATP |
Citriic acid cycle | in MITOCHONDRIA so requires O2 resulting in breaking down in the mitochondria to 6 carbons + O2 + water to produce CO2 resulting in 34-36 ATP gained |
Electron transport chain | in MITOCHONDRIA so requires O2 (same result in ATP as citric acid cycle -only when O2 is present) |
If no glucose... | take form storage; breakdown glycogen to glucose 6 phosphate then glycolysis, citric acid cycle, electron transport chain. |
Still no glucose?...make new glucose | in The LIVER after the glucose supply is all used up; generally, free amino acids are catalyzed to produce ATP; deamination then glycolosis or citric acid cycle |
deamination | ? |
Lipids and ATP | triglycerides catalyzed (breakdown)via process called lipolysis |
lypolysis | glycerol enters glycolysis then fatty acids shipped to mitochondria to citric acid cycle and elctron transport chain so need ATP; so need O2 |
How do we get fat from fat free food? | Glycerol can be made from glucose through glycolysis then converted to fatty acids then into triglycerides (fat) and then stored as fat |
Cell physiology | Cytoplasm and Nucleus |
Cytoplasm | Cytosol inclusions and organelles |
Cytosol | fluid, gel-like substance |
Inclusions (non-membraneous organelles) | cytoskeleton and ribosomes |
Cytoskeleton | microtubules, intermediate filaments, microfilaments and motor proteins; in cytoskeleton are proteins that support framework of cell, organizing within the cell and maintaing shape and mvmnt |
Ribosomes | make proteins by reading RNA from DNA |
Organelles (membrane bound) | mitochondria, endoplasmic reticulum, golgi complex, lysosomes, peroxisomes |
Mitochondria | ATP production |
Endoplasmic Reticulum | Modify proteins and make specific membranes and lipis, produce hormones |
Golgi Complex | Pkging and sorting proteins to specific locations |
Lysosomes | Recycling Center;Breaking down old materials |
Peroxisomes | Free radicals minimizing damage to nucleus |
Nuclear envelope | hold nucleolus |
Nucleolus | building blocks of ribosomes; are produced here |
Making of a protein | DNA, Transcription, Translation, Sorting, folding modification |
DNA (in making a protein) | parts being controlled by transcription factors |
Transcription | unprocessed mRNA, processed mRNA; copy of DNA (dbl strand) to RNA (single strand)so can get out of nucleus |
Translation | in cytoplasm by ribosome |
Sorting, folding, modification | in cytoplasm if staying in cytoplasm; in endoplasmic reticulum or goli apparatus if beign secreted |
Cell binding | Cell-cell junctions, cell matrix junctions; to neighbors &/or the environment to form tissues |
Cell-cell junctions | Gap junctions, tight junctions, anchoring junctions |
gap junctions | form a pore to allow communication btwn neighboring cells (ATP, Ca, Electrical signals in CM cells) |
tight junctions | form a waterproof barrier preventing material from sliding btwn cells Ex. in STOMACH |
anchoring junctions | strongly attaching cells to neighbors; if not attached to the environment they begin to divide; anchoring inhibits cell division which causes cancer |
Cell-Matrix junctions | focal adhesions, hemidesmosomes |
Tissues | Embryonically/functionally related cells + extracellualr matrix and 4 tissue types |
4 Tissue types | Epithelial tissue, CT, Muscle tissue and Nervous tissue (be able to give an example and what its used for) |
Epithelial Tissue | Lines organs; stomach lining and skin |
Connective tissue | Connects, supports, protects; cartilage, blood, tendons |
Nervous tissue | informs us of environmental change in CNS; signals muscles |
Muscular tissue | Movement and support; skeletal, smooth and cardiac |