| Exothermic Reaction | Reactants have greater amount of energy than the products (energy release) |
| Exothermic Reaction | Reactants have greater amount of energy than the products (energy release) |
| What is a cell, and its roles? | the smallest unit of structure and function of all living organisms
metabolism, homeostasis and reproduction |
| What is the Cell Theory? | • all organisms are made up of one or more cells,
• all the life functions of an organism occur within cells,
• all cells come from preexisting cells.
• energy flow (metabolism and biochemistry) occurs within cells,
• cells contain hereditary information (DNA)
• all cells are basically the same in chemical composition in organisms of similar species. |
| What are cells needs? | -need to get energy from their environment
-need to respond to their environment
-need to reproduce. |
| What is the structure function relationship | • A cell’s function is usually directly related to its structure |
| Covalent Bonds v.s Ionic bonds | Covalent bonds form between atoms that have little if any difference in electronegativity
Ionic bonds form between atoms that are significantly different in electronegativity. |
| What are organic compounds? | Compounds that contain mainly the elements carbon and hydrogen |
| Mixture v.s Compound | • A compound forms when elements combine in fixed proportions and undergo a chemical reaction.
• A mixture forms when substances combine in any proportion without a chemical reaction. |
| What is a polar molecule? | a molecule in which part of the molecule is positively charged and part of the molecule is negatively charged. |
| What are the properties of water? | -cohesion, the tendency for water molecules to stick together
-Boiling point 100 C
-Adhesion, the bonding of a water molecule to another substance |
| What are hydrogen bonds? | Hydrogen bonds form between positively and negatively charged parts of water
molecules. They hold the water molecules together. |
| What is an anabolic reaction | -Body reactions that build up molecules
-Water is removed from smaller molecules to make larger ones |
| Catabolic Reaction | -Body reactions that break down molecules
-Water is used to break bonds in larger molecules to make smaller ones |
| Dehydration Reaction | when molecules combine to form a single, larger molecule and also a molecule of water.
-Called condensation if other molecule is formed instead of water |
| Hydration Reaction | adds water to an organic molecule and breaks the large molecule into smaller molecules. |
| Neutrilization Reaction | When an acid and base react, they form a neutral solution of water and a salt |
| Describe Carbohydrates | -Contains Carbon, hydrogen, oxygen
-provides energy to cells, stores energy, forms body structures |
| Lipids | -contains carbon, hydrogen, oxygen
-stores energy, forms cell membranes, carries messages |
| Protiens | -carbon, hydrogen, oxygen,nitrogen, sulfur
-helps cells keep their shape/structure, and makes up muscles, catalyzes
chemical reactions,carries messages and materials |
| Nucleic Acids | -Contains carbon, hydrogen, oxygen, nitrogen, phosphorus
-contains instructions for proteins, passes instructions from parents to offspring,
helps make proteins |
| Condensation Reactions | -Water is produced from the two molecules being bonded together
-hydrolysis is opposite |
| Disaccharide | If two monosaccharides bond together, they form a carbohydrate called disaccharide
-Simple sugar
-maltose, sucrose |
| Redoc Reactions? | Involves transfer of one or more electrons from one reactant to another |
| Oxidation | Losing Electrons |
| Reduction | Gaining electrons |
| Monosaccharides | -Primary cell energy source
-Short and long term energy storage
-Simple sugar
ex. glucose, fructose |
| Polysaccharides and function | -made up of many monosaccharides
-complex carbs
-energy storage and structural support |
| Examples of Polysaccharides | Starch: We break down starch for energy
Glycogen: Our form of storage of energy
Cellulose: Needed for digestion |
| Triglecerides | -Fat storage
-glycerol + 3 fatty acids |
| Fatty Acid | Long carbon-hydrogen chain, containing carboxyl group at end |
| Saturated Fatty acids | -Hard to break down
-saturated fatty acids can be packed together very tightly. This allows organisms to store chemical energy very densely.
ex. beef, butter, cheese |
| Unsaturated fatty acid | -Easier to break down
-essential for human health
-form bended chains
ex. seeds, nuts olive oil |
| Phospholipids | -A phosphate group replaces one of the fatty acids attached to the glycerol
-major cell membrane component |
| What are proteins required for | structure regulation, function of the bodies tissues and organs |
| What are proteins needed for | tissue repair and construction, structural support, transport and storage
-used to replace worn-out dead cells by building cell structures |
| Copmosition of proteins | Composed of 20 amino acid building blocks |
| Amino acids functional groups | -amino group
carboxyl group
-remainder group |
| Formation of protiens | -peptide bonds join individual amino acids together |
| Poly-peptide chain | multiple amino acids joined by peptide bonds |
| Primary structure | amino acids bond together to from polypeptide chain |
| Secondary Structure | Polypeptide chain coils and folds at various locations along its length |
| Tertiary Structure | R groups interact to permanently change the shape of chain |
| Quaternary Structure | 2 or more polypeptides come together to form the protien |
| What do nucleic acids consist of | 1 or 2 long chains of repeating units called nucleotides |
| DNA | -provides instructions for building proteins
-double stranded
-4 nitrogen bases (Adenine, guanine, thymine, cytosine) |
| RNA | -involved in the synthesis of a protein
-has ribose sugar
-single-stranded
-Uracil instead of Thymine |
| Fluid mosaic model | Describes plasma membrane as a fluid combination of phospholipids, cholesterol, proteins |
| Plasma membrane | Forms barrier b/w cytoplasm and environment outside cell |
| Hydrophilic | Water loving |
| Hydrophobic | Water fearing |
| Phospholipid bilayer | -Consists of proteins, cholesterol, carbs, and cytoskeleton
-opens and closes paths through cell membrane |
| What does a cell membrane contain | -phospholipids, cholesterol, channel protein, peripheral protein, carrier protein, glycoprotein |
| Simple diffusion | -Passive transport
-moves with a concentration gradient (high to low)
-does not require a transport protein
-caused by random motion and collision of molecules |
| Passive transport | transport of small molecules across the cell membrane
-doesn't require energy |
| Facilitated diffusion | -passive transport
-moves with the concentration gradient
transport proteins help things pass |
| ATP | Active transport (uses energy)
-molecules go against the concentration gradient (low to high)
energizes transport protein |
| Endocytosis | Cell fuses with the molecule folding inwards |
| Exocytosis | -Used to get rid of cell waste
-Take valuable materials out that cell made
-large molecules released |
| Phagocytosis | Movement of large molecules through the membrane
- uses a vesicle to swallow or expel material |
| Entropy | -during energy transformation, energy is lost as thermal energy
Measure of tendency of system to become unorganized |
| Exothermic Reaction | Reactants have greater amount of energy than the products (energy released)
Catabolic |
| Endothermic reaction | Reactants begin with less energy than products have at the end. (energy must be supplied to facilitate reaction)
Anobolic |
| Metabolic pathways | A stepwise sequence of reactions in cells
1. Substrate converted into the product by the first enzyme in the pathway
2. product of first reaction becomes substrate for next reaction
3. sequence continues until final product is made from initial substrate |
| Substances involved in metabolic reaction | -Substrates (reactants)
-Enzymes
Cofactors
-energy carriers (mainly ATP)
-End products (product of reaction) |
| Enzymes | -protein cells used to speed up bio reactions by lowering the activation energy
-position substrates into active sites |
| Exergonic Reaction | Energy is released
products have less chemical energy than reactants
requires activation energy |
| Endergonic | energy must be supplied
products have more chemical energy than reactants |
| Catalyzed Reactions | has a catalyst which speeds up the reaction by reducing activation needed for reaction to occur |
| How do enzymes work | Have surface depressions called active sites which allow specific molecules to bond to the enzyme |
| Lock and Key Model | Molecules that have the right shape to fit the active site can attach for chemical change to occur |
| Induced Fit Model | -Molecules are flexible and can change shape
-Function by:
1. bringing 2 substrates together and facilitating a bond to from b/w them
2. breaking substrate to produce 2 or more products |
| Factors affecting enzyme activity | Temperature, PH, presence of inhibitors |
| Competitive inhibitor | Another substance binds to the active site, preventing substrate from binding there |
| Non competitive inhibitor | Another substance binds to enzyme at site other than active site |
| Allosteric | Inhibitor binds to separate site on enzyme changing its shape either inhibiting or activating its function |
| Why do we need enzymes | Without enzymes, animals would not be able to break down food molecules quickly enough to provide the energy and nutrients they need to survive |
| Sterols | Used by body to make certain hormones
sterol cholesterol is an important part of cell membranes |
