1. Lecture Slides in PowerPoint by Jerry L. Cook
Essentials of Human Anatomy & Physiology
Seventh Edition
Elaine N. Marieb
Chapter 2 Biochemistry
Slides 2.1 – 2.20
Lecture Slides in PowerPoint by Jerry L. Cook
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

2. Composition of the Body
Elements
96% of the body is made from four elements
Carbon (C)
Oxygen (O)
Hydrogen (H)
Nitrogen (N)
Slide 2.2
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

3. Important Inorganic Chemicals
Water
Most abundant inorganic compound
Vital properties
High heat capacity- does not change temperature easily
Chemical reactivity- serves as a base for reactions
Cushioning
Expands when it freezes
pH of 7 (neutral)
Slide 2.2
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

4. Important Inorganic Chemicals
Salts- Vital to many body functions
Include electrolytes which conduct electrical currents
ex.- NaCl = sodium chloride, Ca3(PO4)2= calcium phosphate
When ionic balance is severely disturbed, virtually nothing in the body works.
Slide 2.2
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

5. Acids Acids are electrolytes/ Ionize and dissociate in H2O.
They can release hydrogen ions (H+). Protons donors.
HCl (Hydrochloric acid) H+ (proton) + Cl- (anion)
Low pH (below 7), Taste sour
If acid ionize completely: strong acid (Ex: HCl)
If ionize incompletely: weak acid (Ex: acetic acid)
In the body: gastric juice, uric acid, vitamin C, amino acids, nucleic acids, lactic acid, fatty acids
Slide 2.2
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

6. Bases High pH (above 7), Taste bitter, feel slippery Proton aceptors
Hydroxides are common inorganic bases.
They ionize and dissociate in water forming OH- ion
NaOH Na+ + OH-
OH- containing bases are strong
Weak bases: HCO3-,NH3
Common Foods- baking soda
In body: blood, semen
Slide 2.2
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

7. Important Inorganic Compounds
Neutralization reaction
Acids and bases react to form water and a salt
Ex.-
HCl + NaOH H2O + NaCl
Slide 2.24
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

8. pH Measures relative concentration of hydrogen ions (H+) in moles/L
pH below 7 = acidic
pH 7 = neutral
pH above 7 = basic
A solution with pH 6 has 10 times as many H+ ions as a solution with a pH of 7.
Figure 2.11

9. Acid-base balance regulation in the body
Cells are extremely sensitive to slight changes in pH.
Kidneys, lungs and buffers carefully regulate the pH balance.
Buffers are present in body fluids.
Chemicals that can regulate pH change by taking up excess H+ or OH- ions.

10. Acid-base balance regulation in the body
Homeostasis of pH is tightly controlled
Extracellular fluid = 7.4
Blood = 7.35 – 7.45
< 6.8 or > 8.0 death occurs
Acidosis (acidemia) below 7.35
Alkalosis (alkalemia) above 7.45

11. Examples of pH imbalance in the body
If blood pH begin to dip into the acid range, the amount of oxigen that hemoglobin can carry to body cells begins to fall rapidly to dangerous low levels.
Significant drops in pH also interferes with cell enzyme systems.
It can affect electrolytes balance (Na+, K+, Cl-) and hormones

12. Important Organic Compounds
Carbohydrates
Contain carbon, hydrogen, and oxygen in roughly a 1:2:1 ratio
Include sugars and starches
Classified according to size
Slide 2.26
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

13. Carbohydrates Found in plants Functions: Used by all cells for energy
Our body’s primary source of energy
Slide 2.26
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

14. Carbohydrates Monosaccharides – simple sugars Examples
- Glucose - Galactose
- Fructose - Deoxyribose
- Ribose

15. Carbohydrates Disaccharides – two simple sugars joined Examples:
Sucrose = Glucose and Fructose
Maltose = Glucose and Glucose
Lactose = Glucose and Galactose

16. Carbohydrates
Polysaccharides – long branching chains of linked simple sugars
Ex.-
Starch and cellulose- plant polysaccharides (cellulose is indigestible)
Glycogen- animal polysaccharide
Stored in muscle and liver

17. Lipids Lipids Most are insoluble in water
Contain carbon, hydrogen, and oxygen
Monomers are fatty acids and glycerol
Most are insoluble in water
Slide 2.29
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

18. Lipids Can be found in oils and waxes Sometimes referred to as “fats”
Functions:
Energy storage
To cushion organs
Insulation
Part of the plasma membrane
Slide 2.29
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

19. Lipids Saturated- all single bonds Solids at room temp. Animal fats
“Pile up” on sides of vessels
Unsaturated- some double bonds
Liquids at room temp.
Plant fats
Lipids
acid.jpg

20. Lipids Common lipids in the human body Neutral fats (triglycerides)
Found in fat deposits
Composed of 3 fatty acids and glycerol
Source of stored energy
Slide 2.30a
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

21. Lipids Common lipids in the human body (cont.) Phospholipids
Form cell membranes
Composed of:
2 Fatty acids
Glycerol
Phosphate
head
Slide 2.30b
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

22. Lipids
Figure 2.14a, b
Slide 2.31
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

23. Types of Lipids: Steroids
-Examples: cholesterol, bile salts, vitamin D, and some hormones
Figure 2.14c
Slide 2.32
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

24. Proteins Made of amino acids 20 different amino acids
Contain carbon, oxygen, hydrogen, nitrogen, and sometimes sulfur
Slide 2.33a

25. Proteins Can be found in meat, animal products, and beans Functions:
Maintains cell growth/formation of new body tissue
Helps build and repair body tissue
Aids in the contraction of muscle tissue
Aids in the formation of enzymes, some hormones, and antibodies
Provides energy if sufficient carbohydrates and fats are not supplied by diet
Slide 2.33b
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

26. Proteins Essential amino acids- needed in diet
Non-essential amino acids- made in body
Account for over half of the body’s organic matter
Provides for construction materials for body tissues
Plays a vital role in cell function
Act as enzymes, hormones, and antibodies
Slide 2.33b
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

27. Types of Proteins: Enzymes
Act as biological catalysts
Increase the rate of chemical reactions
End in “–ase”

28. Types of Proteins: Enzymes
Substrate- the substance on which an enzyme is acting
Active site- the area on the enzyme to which the substrate binds

29. Types of Proteins: Enzymes
Things that denature (deactivate) enzymes:
Heat
pH change
Addition of ionic substances

30. Nucleic Acids Composed of nucleotides Sugar (ribose or deoxyribose)
Phosphate
Nucleotide bases
A = Adenine
G = Guanine
C = Cytosine
T = Thymine (Only in DNA)
U = Uracil (Only in RNA)
A bonds to T (U), G to C

31. DNA (Deoxyribonucleic Acid)
The “Blueprint” of life
Provides instruction for every protein in the body
Directs growth and development
Contains genes

32. DNA (Deoxyribonucleic Acid)
Organized by complimentary bases to form double helix- 2 strands
Replicates (copies itself) before cell division
Makes up chromosomes/ chromatin

33. 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
Slide 2.37
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

34. How ATP Drives Cellular Work
ATP has 3 phosphates attached (P)
Removal of a P releases energy from the bond, leaving ADP
Removal of another P releases less energy, leaving AMP