NOTES: Chemistry of Life I. Chemical Compounds A. Substances formed from elements joined together. B. Two basic types of chemical compounds: 1. Organic Compounds a. Based on a chain of 2 or more carbon atoms. b. Mainly the elements: C,H,N,O. 2. Inorganic Compounds everything else.
C. Important Qualities of Carbon: (try to find 3 from the video clip) (episode 1 from 30 seconds to end) Bonds with most other elements. Forms many bonds (up to 4). Can form molecules of many different shapes. II. Macromolecules (aka: Biomolecules) A. Large, organic molecules that make up living things. B. Macromolecules are polymers (complex molecules) made of many monomers (smaller molecules) attached together.
C. Four types of macromolecules: (8min) https://www.youtube.com/watch?v=yo244p1e9qm In groups of 1-2 people, chalkboard a tree map for the important things about the 4 macromolecules.
III. Four types of macromolecules: 1. Carbohydrates a. sugars and starches b. made of monomers called monosaccharides c. all have same chemical formula: C 6 H 12 O 6 d. simple structure so quickly broken down by our body for quick, short energy (4cal/g). d. tip: most end in -ose. e. Examples: bread, pasta, fruits, veggies, candy, etc. 2. Lipids a. fats, waxes and oils b. made of monomers called fatty acids c. insoluble in water d. energy storage, cell membranes, hormones (9cal/g) e. Examples: lard, vegetable oil, grease, etc.
3. Proteins a. form many body structures (skin, hair, muscle, etc.) b. made of monomers called amino acids c. complex structure so broken down by body slowly into long-lasting energy (4cal/g) d. Examples: meat, eggs, milk, etc. e. enzymes proteins that act as catalysts to speed up chemical reactions in our bodies. 4. Nucleic Acids a. Commonly called DNA and RNA b. made of monomers called nucleotides. c. storage of genetic information.
IV. Chemical Reactions in Living Things A. Any process that changes one substance into a new substance. B. Reactants Products (old substances) (new substances) C. Thousands happening in your body every second! D. Examples of chemical reactions in living things: 1. Photosynthesis a. How plants convert sunlight and raw materials into stored energy in the form of carbohydrates (sugars and starches). b. Happens in the chloroplasts of plant cells. c. Chemical equation: Sunlight
2. Cellular Respiration a. How plants and animals convert carbohydrates (stored energy) into usable energy for growth, movement, reproduction, etc. b. Happens in the mitochondria of ALL cells. c. chemical equation: Enzymes
E. Photosynthesis and cellular respiration are connected into a cycle: Solar Energy (sunlight) Usable Energy (growth, movement, etc.) Photosynthesis (makes C 6 H 12 O 6 ) Stored Energy (C 6 H 12 O 6 ) Cellular Respiration (break C 6 H 12 O 6 for energy)
V. Nutrients and Energy A. Nutrients 1. Materials your body needs to survive 2. Six classes of nutrients: a. water-makes up most of our body -need at least 1 liter per day b. carbohydrates-sugars and starches -quick energy c. fats-energy storage -hormone production d. proteins-builds new tissues -enzymes that catalyze reactions in our bodies e. vitamins-organic molecules that catalyze reactions in our bodies EX) B, C, A, D, E, K f. minerals-inorganic molecules that catalyze reactions in our bodies EX) nitrogen, phosphorus, potassium, calcium, iron
B. Calories 1. The unit used to measure the amount of energy in the chemical bonds of food. 2. One calorie is how much energy it takes to raise the temperature of 1 gram of water by 1 C.
3. Need about 2,000 calories a day. 4. 1g carbohydrate = 4cal 1g protein = 4cal 1g fat (lipid) = 9cal 5. Every 3,500 extra calories = 1 pound stored fat C. Metabolism 1. The total energy use of all the chemical reactions happening in your body. 2. 3. Basal Metabolic Rate (BMR) a. The minimum number of calories needed to keep a resting individual alive for 24 hours. b. Things that can change your BMR: -age ( as you get older) -height (tall people have BMR) -pregnancy ( BMR) -stress ( BMR) -temperature (hot & cold BMR) -starvation ( BMR) -body fitness (lean muscle BMR, fat tissue BMR)
Formulas for calculating BMR: Males=66+(13.7(weight/2.2))+(5(height in inches*2.54))-(6.8*age) Females=655+(9.6(weight/2.2))+(1.7(height in inches*2.54))-(4.7*age) Example: Joe weighs 150 pounds, is 5 6 tall, and is 21 years old. BMR=66+(13.7(150pounds/2.2))+(5(66inches*2.54))-(6.8*21years) =66+(13.7(68.18))+(5(167.64))-(142.8) =66+934.066+838.2-142.8 =1695.5 calories per day BMI Calculator http://apps.nccd.cdc.gov/dnpabmi/ Interpreting the results http://www.cdc.gov/healthyweight/assessing/bmi/childrens_bmi/about_childrens_bmi.html
VI. Water A. Most important compound to living organisms B. Earth is 75% water (but only 1% is drinkable) C. Your body is 60-65% water D. Necessary for all chemical reactions in your body E. Transports things throughout your body F. Important properties of water: 1. Water molecule is polar a. electrons shared unequally gives molecule positive and negative ends b. makes water the universal solvent (polar molecules attract each other) 2. Cohesion a. Water molecules stick to themselves v tightly b. Prevents evaporation c. How bugs can sit on top of water d. How water gets sucked up plants 3. Resists temperature changes a. Creates a stable environment for fish b. Stabilizes weather of land near water 4. Expands and floats when frozen a. Protects aquatic life in winter
Examples of chemical rxns in our bodies: 1. Hot Cheetos: hot chemicals pain (irritated trigeminal nerve) endorphins (opium-like) addictive high 2. Mountain Dew: caffeine stimulates adrenal gland *increased heart rate, bp, blood flow to muscles *causes liver to release glucose blocks adenosine receptors (adenosine calms cellular activity)