Introduction to Biochemistry. DR. Wejdan Aldajani BIOC 371

Transcription

1 Introduction to Biochemistry DR. Wejdan Aldajani BIOC 371

2 What is Biochemistry? علم الكيمياء الحيوية Bios= life in Greek. Biochemistry= chemistry of life. Biochemistry is the science concerned with studying the various molecules that occur in living cells and organisms and with their chemical reactions. 2

3 Matter, element, and atom Matter: anything that occupies space and has mass (All matter is made up of substances called elements). Element: simplest form of a substance - which have specific chemical and physical properties and cannot be broken down into other substances through ordinary chemical reactions. (e.g. Gold, lead, carbon etc.) There are 118 elements, but only 92 occur naturally. The remaining elements have only been made in laboratories and are unstable. Atom: the smallest unit of matter that retains all of the chemical properties of an element. The atom is made up of 3 particles: Particle Proton Neutron Electron Charge + Neutral - 3

4 النظائر ISOTOPES Atoms of the same element that HAVE A DIFFERENT NUMBER OF NEUTRONS Some isotopes are radioactive. This means that their nuclei is unstable and will break down over time. 4

5 COMPOUNDS المركبات A substance formed by the chemical combination of 2 or more elements in definite proportions. for example : water, salt, glucose, carbon dioxide 5

6 Organic-Contain C, H, O, and N in some ratio. e.g. Carbohydrates, Proteins, Lipids, Nucleic Acids Inorganic- usually "support" life - no specific ratio of C, H, and O e.g. Water (H 2 O), Carbon Dioxide (CO 2 ) The primary difference between organic compounds and inorganic compounds is that organic compounds always contain carbon while most inorganic compounds do not contain carbon 6

7 CHEMICAL BONDS الروابط الكيميائية Chemical bonds hold the atoms in a molecule together. There are 2 main types of chemical bonds: IONIC and COVALENT 7

8 IONIC BONDS األيونية الروابط Occur when 1 or more electrons are TRANSFERRED from one atom to another. When an atom loses an electron it is a POSITIVE charge. When an atom gains an electron it is a NEGATIVE charge. These newly charged atoms are now called IONS. o Example: NaCl (SALT) 8

9 COVALENT BONDS الروابط التساهمية Occur when electrons are SHARED by atoms. These new structures that result from covalent bonds are called MOLECULES. In general, the more chemical bonds a molecule has the more energy it contains. 9

10 المحاليل SOLUTIONS Two parts: SOLUTE Substance that is being dissolved (sugar/salt). SOLVENT - the substance in which the solute dissolves. Materials that do not dissolve are known as SUSPENSIONS. 10

11 األحماض ACIDS Acids: always (almost) begin with "H" because of the excess of H + ions (hydrogen). o EX: HCl hydrochloric acid, H2SO4 sulphuric acid, HNO3 nitric acid Acids turn litmus paper RED and usually taste SOUR. 11

12 القواعد BASES Bases or alkaline: always (almost) end with - OH because of the excess of hydroxide ions (Oxygen & Hydrogen) o EX: NaOH sodium hydroxide, KOH potassium hydroxide, o Bases turn litmus BLUE. Bases usually feel SLIPPERY to touch and taste BITTER. 12

13 األس (ph) Power of hydrogen الهيدروجيني Is a measure of the acidity and basicity of an aqueous solution. The ph scale ranges from 0-14, where 0-5 Acidic 6-7 Neutral 8-14 Basic 13

14 The ph can be determined experimentally by using ph paper or a ph meter 14

15 When an acid reacts with a base they produce a salt and water. This process known as Neutralization (المعادلة ( 15

16 WATER (H 2 O) Water is the predominant chemical component of living organisms, making up 70% or more of the weight of most organisms. There is a specific chemical bond formed between polar molecules in which hydrogen (H) is bound to a highly electronegative atom, such as nitrogen (N), oxygen (O) or fluorine (F). hydrogen bond 16

17 Water is a polar solvent. It can dissolve most biomolecules. It called Universal solvent. hydrophilic hydrophobic Compounds that dissolve easily in water Compounds that do not dissolve in water Other compounds contain regions that are polar and regions that are nonpolar known (amphipathic compounds) 17

18 Electrolytes Electrolytes are compounds that ionize in water to produce aqueous solutions that conduct an electric current. Example: inorganic salts, all acids and bases, and some proteins. Nonelectrolytes are substances that do not ionize, remain as molecules, and do not conduct an electric current. Example: glucose, lipids, creatinine, and urea. Ions that move to the cathode (cations) are positively charged, e.g. Sodium ion (Na+ ). Ions that move to the anode (anions) are negatively charged, e,g, Chloride ion (Cl-). 18

19 What is going to happen if electrolytes are too High Low Blood agglutination, hypertension, nervous tension, migraines, high platelets, kidney problems, adrenal stress, high minerals, cardiac stress, excessive plasma, edema, arthritis, allergies, vascular disorders and high cholesterol. Anemia, cold states, hypotension, nervous exhaustion, headaches, low platelets, kidney weakness, adrenal fatigue, poor retention of minerals, cardiac weakness, low plasma, chronic fatigue, osteoporosis, anxiety, pituitary and muscle weakness. 19

20 Examples from your life Calcium Fluoride: gives tissues elasticity. Ferric Phosphate: is an oxygen carrier. Sodium Chloride: it affects every fluid and solid of the body. Sodium Phosphate: is an acid neutralizer. Potassium Chloride: bonds with tissue salt and causes fibrin. 20

21 Summary What is biochemistry? Matter, element, and atom. Isotopes. Compounds. Chemical bonds. Solutions. Acids and bases. Water. Physical properties. Electrolytes. 21

22 REFERENCES 1. Murray, R., Bender, D., Botham, K., Kennelly, P., Rodwell, V., Weil., P. (2012) Harper s illustrated biochemistry, 29 th edition. Publisher: McGraw Hill Lange. 2. Nelson, D. and Cox, M. (2008) Lehninger principles of biochemistry, 5 th edition. Publisher: W.H. Freeman and company, New York. 3. Harvey, R. and Ferrier, D. (2011) Lippincott s illustrated reviews: biochemistry, 5 th edition. Publisher: Lippincott Williams & Wilkins. 4. Moorthy, K. (2008) Fundementals of Biochemical Calculations, 2 nd edition. Publisher: CRC Press. 22