Bio Test PDF

**Laws of Thermodynamics** - Energy is not created or destroyed; it is just **transferred** - Every time you transfer energy, some it is lost as **heat,** but that heat is taken in somewhere else - *Light bulbs lose heat* - Heat is not usable in univese -...

**Laws of Thermodynamics** - Energy is not created or destroyed; it is just **transferred** - Every time you transfer energy, some it is lost as **heat,** but that heat is taken in somewhere else - *Light bulbs lose heat* - Heat is not usable in univese - Think of a food chain/web\-\--energy is constantly transferred from one to the next. However, every time energy is transferred, there is a net **loss.** - More direct, more energy   A diagram of a bird and a snake Description automatically generated     - Systems will react to achieve **stability** - When chemical reactions occur, they will do so to become **more** stable. - There is always greater **disorder** (entropy) with more stability - Stability=disorder \> more stable less order - In our world, less order over time as reactions occur. - You've just finished cleaning your room. What is more ordered, now or 6 days from now? - Does not take energy to get messy, so easier to be more disorganized, so stability - More ordered when first done (or when a baby) - What is more stable? - When the room is dirty, less organized, more bonds       **Kinetic vs Potential Energy** - Potential - ***Stored*** energy that is capable of being used - *Boulder sitting on the peak of a cliff* - *Glucose chemical bonds*   - Kinetic - Energy of ***motion*** or energy that is working - *Something hits the boulder and makes the boulder roll down*. The **potential** energy is converted into **kinetic** energy - *Glycosis converts to energy*     **Activation Energy**  - Enzymes lower activation energy - Energy comes in many forms: - Chemical - Light - Heat - Electrical - Nuclear   - The amount of energy needed for a chemical reaction to take place is called **activation energy.** - Enzymes help to reduce that cost in living things---they are **catalysts** - in reactions create the optimal enviornment - **Provides surface** for chemical reaction to take place on - **Brings the reactants closer (**make more likely to bond) - **They orient the substrates** in such a way that they will react faster (shifting positions to promote) Enzymes and Energy Thursday, September 5, 2024 8:47 AM Exergonic vs Endergonic Reactions and Processes   Endergonic Reactions - Products have **more** energy than the reactants (take in energy) - Endothermic reactions take in **heat** - Photosynthesis is an example: glucose has far more energy in its bonds than either **water** or **carbon dioxide** - End has more energy stored, so changed from reactants to the products - Think: whole is greater than sum of parts (had to take energy from elsewhere) - *Where did the extra energy in glucose come from?* - From the light energy     - Photosynthesis - glucose gets extra light energy from sun, then transferred to chemical enery, then to light - See image of   Exergonic Reactions - Products have **less** energy than the reactants (lose energy) - Exothermic reactions **release** heat - Respiration is an example: glucose has far more energy in its bonds than either **water** or **carbon dioxide** - *Where did the lost energy in glucose go?* - Free energy is used to make ATP (which mantains life)   - *Hot hand packets, shake and get hot - release heat*   Anabolic Reactions (*anabolic steroids to build muscles)* - Also called a **Synthesis** Reaction - 2 or more reactants are put together to make a product (build things) - **Photosynthesis is** is an example! (carbon dioxide and water - glucose) see below.      Catabolic Reactions - Also called a **Decompostion** Reaction - A reactant is broken down to make two or more products (breaks things) - **Respiration** is an example! (turns glucose into water and carbon dioxide) A diagram of a catabolic decomposing Description automatically generated **Factors that affect enzyme activity:** - A protein's ability to function is determined by its 3-dimensional structure. If this is damaged or disrupted, it can no longer function. It is said to be **denatured** - *See what enzyme looks like - made of covalent and ionic attractions to combine the 3 pieces - the shape determines its function \>* - Things that can denature proteins: - pH - positive and negative O and OH - change the charges of active site/ bonds between - Around 6-8 pH is normal - Pepsin **(acid)** enzyme in stomach - Trypsin **(base)** enzyme in small intestines - alkaline - Enzyme is altered if it is not in the right pH - most enzymes need between 6.8-7.1 - near neutral is best - *Example: you stomach is very acidic so the enzymes in your stomach work at about a more acidic pH. If you get a protein with an abnormal pH, it will denature.* - *See proteins change when cook fish* - Temperature (break apart) - Most work best between 35^o^-40^o^ degrees Celsius - If you heat a protein too much or cool it too much, it will denature and come apart. (changing bonding powers and will not work) - **Not reversable** - Example: *boiling an egg (not reversable) - yolk and leumen solid* - Ion Concentration - shape - \#HATE SALT - sodium positive and cholrine neg clog the active site - Generally, do not like **salt** - Most salt concentrations need to be 0.09% salt because that is the concentration of salt in **living things** - Enzymes function at.09 or less   **Factors that inhibit or stop reaction of enzymes:** 1. **The concentration of the products vs. the concentration of the reactants**- If there is a whole bunch of glucose, it will react a lot and make plenty products. The products will increase and the concentration of the reactants will decrease. - **The more there is, the** greater **the reaction.** - More reactants - more production at beginning, however, slows down - Glucose broken down pyruvic acid, begins quickly, then lowers the reactions for it uses the products - Fix by changing reactants or enzymes ** ** 1. **Competitive inhibition (slow down enzymes)** - There is another molecule that has the same shape and is supposed to fit into the site. So, they will fight over it. When the substrate is in, the reaction will occur. When the inhibitor is in there, the react will **stop** - Penicillin is an antibiotic that inhibits the enzymes bacteria use to create **cell walls** - *Controls food bacteria for these bacteria - competes with substrate to fit in the reaction* - *Think: penicilin beats the race to the substrates in race to enzymes activation site for walls, weaking the cell wall and slowing* - Less enzyme function means **less** cell wall, which means less bacterial cells alive - Bacteria is less affected by penicilin due to evolution and change, causing RESISTANCE   1. **Allosteric regulation (allo-other/different) BOTH ACTIVE AND REGULATORY, so activator needs to meet the allosteric** - Majority of enzymes are allosteric - 2 types of allosteric enzymes: - **Allosteric *activator*:** has 2 sites, one the active site and one where the activator goes. In this case, only when the activator is in its **regulatory** is the active site shaped correctly. - Allows the enzyme to *wake up* and function - **Allosteric *inhibitor*:** - **Noncompetitive inhibition - any molecule that turns it off enzymes** - Not going to have 2 molecules coming from one site; instead the enzyme **has 2 sites,** one the **active site** and the other called the **regulatory site.** - When the reactants start to be used, the inhibitor will attach to the regulatory site. But this causes the active site to change shape. If the active site, changes shape, the substrate cannot bind and the reaction will shut down. - Anything that alters the reaction site will shut down. - Changes enzyme for worse, *turn off the light* - Controls the rate of reaction \> not too much good - *Metabolic processes*     a. **Feedback inhibition (allosteric inhib) (both non+feed are same the only difference is the feedback rather than an OTHER thingy) specific product of enzyme turns off the enzyme, enough product then turns off enzyme** - The final thing you are making is the inhibitor for the first enzyme in the series: it **FEEDSBACK**! It goes back to the **beginning** and shuts the first enzyme down, shutting down the rest of the series. - **Allosteric** sites are the same things as regulatory sites. - Many **metabolic** pathways are shut down this way. - Product made is what stops the reaction from happing further - Product attacks to enzyme (more touching) and right amount shuts it off - *Thermostat takes temp when room is hot so ac on but once it reaches low cool temp, it is triggered to turn off, feeding BACK info*