• Like
The chemistry of life
Upcoming SlideShare
Loading in...5

The chemistry of life

Uploaded on


More in: Technology , Business
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads


Total Views
On Slideshare
From Embeds
Number of Embeds



Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

    No notes for slide


    Protoplasm – refers to the substance associated with life- substance out of which cells and organisms are made
    The basic chemical components that made up the protoplasm are almost the same in almost all cells but they vary in proportionCHEMICAL COMPOSITION
    • Are compounds that do not contain hydrocarbon. It also includes the oxides and sulfides of carbon
    • The most abundant protoplasmic compound ranging from 35-90% of the weight of the protoplasm
    • 2. It is about 60-90%of most living organisms
    • 3. By far, oxygen,hydrogen and carbon are the most abundant elements in the body and account for 93% of its weight. Much of the oxygen and hydrogen is linked together as water molecules
    Universal solvent
    Favors dissociation of an electrolyte
    Has a great fluidity which serves as a vehicle for transport of materials
    High surfae tension
    High specific heat
  • 4. Shown are water molecules adhering to various ions (adhesion), forming hydration shells around them
    Adhesion—Hydration Shells
  • 5. Water resists evaporating (i.e., vaporizing) because hydrogen bonds must be broken in order for water to transition from the liquid to the gas state
    High Heat Vaporization
    -present in the form of cat-ions and anions.
    * Cat-ions
    - K+ and Na+- for conduction of nerve impulse
    - Mg+2 and Ca+2- for muscular contraction
    - Fe +2- for red blood cell formation
    * Anions
    - PO4- - necessary for nucleic acid formation
    - HCO3- - Control of pH in the blood
  • 7. C. GASES
    - the most abundant are oxygen and carbon dioxide
    * Carbon dioxide – carried in three ways:
    1. 5% in solution in the plasma as carbonic acid
    2. 10% in combination with amino groups of hemoglobin
    3. 85% in the form of sodium and potassium bicarbonates (blood salts both in the plasma and RBC
  • 8. * Oxygen
    • Carried by erythrocytes and partly by the plasma necessary during the oxidation process.
    - compounds that contain carbon except for the oxides and sulfides of carbon.
    - The source of the vast diversity of organic molecules found in living things is the bonding capacity of just one of the 92 naturally occurring elements - CARBON
  • 9. * Because life is built largely of Carbon atoms, macromolecules are large carbon-carbon molecules
    • In building large macromolecules carbon usually combines with other carbons, H, O, N, P and sulfur, leading to almost endless variety of organic (carbon based) molecules
  • Organic Molecules fall into 4 groupings:
    1. Carbohydrates
    2. Lipids
    3. Proteins
    4. Nucleic Acids
  • 10. Carbohydrates
    Role: energy storage, structural role
    Not all carbons are macromolecules- some are small: Simple sugars
    The macromolecular form is just a long chain of simple sugars
  • 11. Monosaccharides
    - simple sugar with one 6-carbon sugars
    - E.g., glucose, dextrose, galactose, fructose and pentose (constituents of nucleic acids and nucleotides such as deoxyribose and ribose sugars)
    2. Oligosaccharides (mostly disaccharides)
    - double sugar with two 6-carbon sugars
    Glucose + galactose = lactose
    Glucose + fructose = sucrose
    Glucose + glucose = maltose
  • 12. 3. Polysaccharides
    - a combination of more than 2 monosaccharides that is, a straight or branched chain of hundreds or thousands of sugar units of the same or different kinds
    Cellulose – the structural material in plant cell wall and consists of 2,000 united glucose units
    Glycogen – glucose-storage form that serves as reserve food for animals and is made up of 12-16 glucose units
    Starch- glucose- storage form that serves as reseve food for plants and is made up of 24-26 glucose units
  • 13. Lipids:Fats & Oils
    -insoluble in water, but soluble in organic solvents such as chloroform
    -nonpolar and hence hydrophobic
    - contain higher proportion of hydrogen and much smaller proportion oxygen
    - chemically composed of C, H, and O but they may also contain other elements,particularly phosphorus and nitrogen
    Examples include: Oils (olive, corn…),Waxes (bee’s, ear),Fats
  • 14. Functions:
    True fats furnish concentated fuel of high-energy value and represent an economical form of storage reserves in the body
    2. Some phospholipids form part of the basic protoplasmic structure
    Classes of lipids
    Fatty acids
    - has a long unbranched carbon backbone with a –COOH group at the end
    -in living organisms usually contain an even number of carbon atoms
  • 15.
    • The length of the chain affects the fluidity of the molecule; short chains are fluid at room temperature whereas long-chained fatty acids tend to be solid
    • 16. -C-C-C-C-C-C-C-C-C-C-C-COOH
    • 17. Examples of lipids with fatty acids are:
    • 18. 1. glycerides – the body’s most abundant lipids and its richest surce of energy. With 1,2 or 3 fatty acid tails attached to a backbone of glycerol
    • 19. 2. Saturated fats- including butter and lard, which tend to be solids at room temperature. Saturated means all the C atoms in the fatty acid tails are joined by single C-C bonds ans as many H atoms as possible are linked to them
  • 3. Unsaturated fats or oil
    - tend to be liquid at room temperature. One or more double bonds occur between the C atoms in the fatty acid tails
    - It is liquid because the double bonds create a “kink” that disrupt packing between tails thereby making the molecules less densely packed and move about more freely
    - some amounts of unsaturated fats are important in nutrition (e.g., lenoleic acid for rats)
  • 20. Saturated & Unsaturated F.A.
  • 21. Fatty Acids–Saturated, Unsaturated
  • 22. 4. Waxes
    – Some wax secretions form coatings that help protect, lubricate, and maintain the pliability of skin and hair while other help make feathers water repellant
    II.Fats or triglycerides
    - fat molecules have twice as much energy per unit weight as CHO, which is why the body’s energy requirements are met much more readily on a high-fat diet
  • 23. Functions:
    Important as energy-storage molecules in living organisms
    2. Provide insulation, cushioning and protection for various parts of the body
    Composed of (building blocks):
    - also called glycerin with a backbone of 3 carbon atoms, each with hydroxyl group
    2. 3 fatty acids
    - formed by condensation reaction or dehydration synthesis (reaction joining 2 compounds with resultant formation of water) of glycerol and 3 fatty acids
  • 24. Fatty Acids–Cis, Trans, Saturated
  • 25. -In general, animal fats tend to be saturated while most vegetable fats (oil) are unsaturated.
    III. Phospholipids
    - are lipids wherein the phosphate group substituted for one of the 3 FA
    - among the most common are those composed of 1 unit of glycerol, 2 units of FA and 1 phosphate group
    are sometimes calleed “schizophrenic” molecules because of their split personality-one end is soluble in water and the other end is not.
    - The main structural component of the cell membrane
  • 26. Phospholipids
  • 27. IV. Steroids
    -differ markedly from fats, oils, and phospholipids and are not formed from condensation reactions between FA and alcohols
    - composed of 4 linked rings of C atoms with various side groups attached to the rings
    - are classified as lipids because they are also soluble in organic solvents and relatively insoluble in water
    Cholesterol is a steroid that is:
    1. Important constituent of mammalian cell membranes
  • 28. 2. Used in the synthesis of vitamin D and certain hormones (e.g., sex hormones)
    3. Proteins
    • Far more complex than carbohydrates and lipids
    • 29. Play a leading role in both the structure and function of living organisms
    • 30. Contains four essential elements: carbon, hydrogen, oxygen and nitrogen;most proteins also contain some sulfur.These elements are bonded together through condensation reaction to form the building block molecules called amino acids `
  • Fibrous protein (e.g., collagen)
    Globular versus Fibrous
    Globular protein (e.g., hemoglobin)
  • 31. Functions:
    Major components of muscles and are responsible for muscle contraction (contractile proteins like actin & myosin)
    For structural support
    A. Elastin- gives the skin its elasticity
    B. Keratin- The principal protein of hair, horns and claws including the silk of spider webs & silkmoth cocoons
    3. Energy storage (albumin in eggs and casein in milk)
    4. For oxygen transport in blood (hemoglobin)
    5. Immune response (antibodies)
  • 32. 6. Hormones (a control chemical sceted in one part of the body that effects other parts of the body) – e.g., insulin & growth hormones
    7. Catalysts of biological reaction (protein enzymes guide all chemica reactions that occur inside the cell)
    8. Poison (rattlesnake venom)
    4. Nucleic acid
    -are the materials of which genes are made of
    - they are also the messenger substances that convey information that governs the synthesis of proteins amd thereby determines the structural attributes of the cell and regulates the cell’s other functional activities
  • 33.
    • Composed of the building blocks called nucleotides that are composed of: 5-carbon sugar, a phosphate group, and an organic nitrogen-containing base. Both the phosphate group and nitrogeneous base are covalently bonded to the sugar
    • 34. - deoxyribonucleic acid acid (DNA) is the nucleic acid most genes are made of. It is compose of the following:
    • 35. 1. Deoxyribose (the sugar component)
    • 36. 2. Nitrogeneous bases
    • 37. A. Purine(Double-ring structure)
    • 38. 1. adenine 2.guanine
  • B. Pyrimidines (Single-ring structure)
    Cytosine 2. thymine
    Nitrogeneous base pairing
    Adenine-thymine A-T
    Guanine-cytosine G-C
    2. RNA (Ribonuceic acid)
    Nitrogeneous base pairing
    Adenine – uracil A-U
    Guanine – cytosine G-C
  • 39. Nucleic acid
    Central Dogma
    Nucleic acid
    Nucleic acid
    Nucleic acid
    + protein
    Nucleic acid
  • 40. DNA and RNA
  • 41. Base Pairing
  • 42. DNA and RNA
    Note that T pairs with A (T:A) and C pairs with G (G:C)