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Chem chap #2
a&p chap 2 Chem
Question | Answer |
---|---|
Chemistry in Anatomy and Physiology | body functions depend on cellular functionscellular functions result from chemical change |
Matter | anything that takes up space and has weight; composed of elements |
Chemical elements | substances that cannot be broken down by chemical means into simpler substancesExamples: carbon, hydrogen, and nitrogen |
Atoms | Smallest particle of an element |
Atomic Structure | Atoms composed of subotomic particles |
Protons | carry a positive charge p = protons |
Nuetrons | carry a charge n = neutrons |
Electrons | carry a negative charge pink dot = electrons |
Nucleus | composed of protons and neutronselectrons move around it |
Atomic Number | number of protons in the nucleus of one atomeach element has a unique atomic numberequals the number of electrons in the atom |
Atomic Mass | the number of protons plus the number of neutrons in one atom electrons do no contribute to the weight of the atom |
Molecules | particle formed when two or more atoms chemically combine |
Compound | particle formed when two or more atoms of different elements chemically combine |
Chemical formulas | depict the element present and the number of each atom present in the molecule |
Electrons | found in regions of space called orbitals(energy cells)each shell can hold a limited number of electrons. Lower shells are filled first. If the outermose shell is full, the atom is stable. |
For atoms with atomic numbers of 18 or less | the first shell can hold up to 2 electronsthe second shell can hold up to 8 electrons the third shell can hold up to 8 electrons |
Ions | atom that ha gained or lost an electron(s), electrically charged, atoms form ions to become stable |
Ionci Bond | an attraction between positive and negative ions |
Ionic compounds | dissociate when tehy dissolve in water. Called electrolytes because they can conduct eletrical current in water |
Composition and concentration of electrolytes | must be kept within normal limits for normal body function |
Covalent Bond | formed when atoms share electrons |
Structural Formulas | show how atoms bond and are arranged in various molecules |
Inorganic Molecules | generally do not contain C. Usually smaller than organic molecules. Water, oxygen, carbon dioxide, and inorganic salts. |
Organic Molecules | Contain C and H. Usually larger than inorganic molecules. Charbohydrates, proteins, lipids, and nucleic acids |
Water H2O | two-thirds of the weight of an adult human |
Oxygen O2 | used by organelles to release energy from nutrients |
Carbon dioxide CO2 | waste product released during metabolic reactions |
Inorganic Salts Na+, Cl-, K+, Ca2+ | abundant in body fluids and cells. Many metabolic processes |
Electrolytes | substances that release ions in water NaCl -> Na+ + Cl- |
Acids | electrolytes that release hydrogen ions in water. HCl-> H+ + Cl- |
Bases | substances that release ions that can combine with hydrogen ions. NaOH -> Na+ + OH- |
Salts | electrolytes fromed by the reaction between an acid and a base. HCl + NaOH --> H2O + NaCl |
pH scale | concentration of hydrogen ions in solutions |
Acidic | pH less than 7; greater concentration of H+ |
Neutral | pH 7; equal concentrations of H+ and OH- |
Alkaline | pH greater than 7; greater concentration of OH- |
Buffers | chemical or chemicals that cn either pick up or release H+ to keep a solution's pH constant. Maintain normal pH of body fluids. Needed because slight pH changes can be harmful to body cells |
4 main types of biological macromolecules | Carbohydrates, lipids, proteins, and nucleic acids |
Carbohydrates | provide energy to cells, supply materials to build cell structures, water soluble, contain C, H, and O. ratio of H to O close to 2:1 (C6H12O6) |
3 main types of carbohydrates | monosaccharides = glucose and frutose, disaccharides = sucrose and lactose, polysaccharies = glycogen and cellulose |
Monosaccharides (simple sugars) | simplest carbohydrates. Glucos is major fuel for cells. Fructose and galactose are 6-C simple sugars found in foods |
Disaccharides | formed by chemically combining 2 monosaccharides. Maltose, sucrose, and lactose |
Polysaccharides | fromed by chemically combining many monosaccharides. Glocogen: animal carbohydrate storage. Starch: plant carbohydrate storage |
Lipids | soluble in organic solvents. Fats (triglycerides) used for energy and cell membranes. Contain C, H and O but less O than carbohydrates |
Saturated fats | animal triglycerides or fats. All C-C bonds are single bonds. Solid at room temperature. Examples: butter and lard |
Unsaturated fats | Plant triglycerides or oils. One or more doulde C-C bonds. Monounsaturated and Polyunsaturated. Examples: olive oil and corn oil |
Phospholipids | phosphate replaces a fatty acid. Major components of cell membranes |
Sterols | component of cell membrane. Basis for some hormones |
Proteins | structural material, receptors, enzymes, antibodies, building blocks are amino acids, held together with peptide bonds. |
Condensation Synthesis | water is removed when bond is formed |
hydrolysis | water is added when bond is formed |
Catalyst | chemical that speeds reaction by is not part of the reaction (and is not changed by the reaction) |
Enzymes | brings together the substrates and allow them to react more easily |
Adenosine Triphosphate (ATP) | modified nucleotide with adenosin and 3 phosphates. Temporarily stores energy extracted from nutrients by cells. Only molecule to provide immediate energy to keep cellular processes going (powers chemical reactions) |
ATP | its abilities are due to the alternating formation and breakage of high-energy phosphate bonds |