1. Chapter 2 part 2: Biochemistry

2. Biochemistry: Essentials for Life
Organic compounds
Contain carbon
Most are covalently bonded
Example: C6H12O6 (glucose)
Inorganic compounds
Lack carbon
Tend to be simpler compounds
Example: H2O (water)

3. Important Inorganic Compounds
Water
Most abundant inorganic compound
Vital properties
High heat capacity
Polarity/solvent properties
Chemical reactivity
Cushioning

4. Important Inorganic Compounds
Salts
Easily dissociate into ions in the presence of water
Vital to many body functions
Include electrolytes which conduct electrical currents

5. Important Inorganic Compounds
Acids
Release hydrogen ions (H+)
Are proton donors
Bases
Release hydroxyl ions (OH–)
Are proton acceptors
Neutralization reaction
Acids and bases react to form water and a salt

6. pH Measures relative concentration of hydrogen ions
pH 7 = neutral
pH below 7 = acidic
pH above 7 = basic
Buffers—chemicals that can regulate pH change
Interactive pH Scale

7. Important Organic Compounds
Carbohydrates- Glucose, cellulose, glycogen, starch
Lipids- Phospholipids, steroids, prostaglandins
Proteins- Enzymes, insulin, albumin, hemoglobin, collagen
Nucleic acids- DNA, RNA

8. Important Organic Compounds
Carbohydrates
Contain carbon, hydrogen, and oxygen
Include sugars and starches
Classified according to size
Monosaccharides—simple sugars
Disaccharides—two simple sugars joined by dehydration synthesis
Polysaccharides—long-branching chains of linked simple sugars

9. What role do carbohydrates play in the body?
1. They serve as the principal source of body energy.
2. They contribute to cell structure and synthesis of cell products.
3. They form part of the structure of DNA and RNA (deoxyribose and ribose are both sugars).
4. They are converted into proteins and fats.
5. They function in food storage (glycogen storage in the liver and skeletal muscles).

10. Carbohydrates
6 carbon sugar (hexose)
5 carbon sugar (pentose)

11. dehydration synthesis and hydrolysis
Hydrolysis- the addition of water to break down a molecule into the two parts.
Dehydration synthesis is the removing of the hydroxl(-OH) and the hydrogen atoms from two organic substances which merges them into one(covalent bond).

13. Important Organic Compounds
Lipids
Contain carbon, hydrogen, and oxygen
Carbon and hydrogen outnumber oxygen
Insoluble in water
Common lipids in the human body
Neutral fats (triglycerides)
Found in fat deposits
Composed of fatty acids and glycerol
Source of stored energy

14. Lipids
Figure 2.15a

15. Lipids Common lipids in the human body (continued) Phospholipids
Form cell membranes
Steroids
Include cholesterol, bile salts, vitamin D, and some hormones

16. Lipids
Figure 2.15b

17. Lipids Cholesterol The basis for all steroids made in the body
Figure 2.15c

18. Important Organic Compounds
Proteins
Made of amino acids
Contain carbon, oxygen, hydrogen, nitrogen, and sometimes sulfur

19. Functions of Proteins and Examples
Enzyme- Trypsin, chymotrypsin, sucrase, amylase
Transport and storage of molecules- Hemoglobin, myoglobin
Motion- Actin, myosin, tubulin (ciliary motion)
Structural support- Collagen, elastin
Immunity-Antibodies- (immunoglobulins)
Neural communication- Endorphins, rhodopsin (pigment for light reception in the eye)
Intercellular messenger- Insulin, glucagon, growth hormones

20. Proteins Amino acid structure Contain an amine group (NH2)
Contain an acid group (COOH)
Vary only by R groups

21. Amino acids 20 Amino Acids Glycine (Gly) Serine (Ser) Lysine (Lys)
Alanine (Ala)
Threonine (Thr)
Arginine (Arg)
Valine (Val)
Asparagine (Asn)
Histidine (His)
Leucine (Leu)
Glutamine (Gln)
Aspartic acid (Asp)
Isoleucine (Ile)
Tyrosine (Tyr)
Glutamic acid (Glu)
Methionine (Met)
Cysteine (Cys)
Proline (Pro)
Phenylalanine (Phe)
Tryptophan (Trp)

22. Enzymes Act as biological catalysts
Increase the rate of chemical reactions
Figure 2.18a

23. Enzymes
Figure 2.18b

24. Important Organic Compounds
Nucleic Acids
Provide blueprint of life
Nucleotide bases
A = Adenine
G = Guanine
C = Cytosine
T = Thymine
U = Uracil
Make DNA and RNA
Figure 2.19a

25. Purines & Pyrimidines
Purines consist of a six-membered and a five-membered nitrogen-containing ring, fused together.
Pyridmidines have only a six-membered nitrogen-containing ring.

26. Nucleic Acids Deoxyribonucleic acid (DNA)
Organized by complimentary bases to form double helix
Replicates before cell division
Provides instructions for every protein in the body
Figure 2.19c

27. Important Organic Compounds
Adenosine triphosphate (ATP)
Chemical energy used by all cells
Energy is released by breaking high energy phosphate bond
ATP is replenished by oxidation of food fuels

28. Adenosine Triphosphate (ATP)
Figure 2.20a

29. Figure 2.21 Membrane protein P P Solute Solute transported (a)
Transport work
ADP
ATP + P
Relaxed muscle cell
Contracted muscle cell
(b)
Mechanical work P X P X Y + Y
Reactants
Product made
(c)
Chemical work
Energy liberated during oxidation of food fuels used to regenerate ATP
Figure 2.21