Chemical level

These elements make up the majority of our bodies

Elements are given chemical symbols such

1.  O = oxygen
2.  C = carbon
3. H = hydrogen
4. N = nitrogen

Trace Elements of the Human Body

1. Aluminium (Al)
2. Boron (B)
3. chromium (Cr)
4. cobalt 
5. copper (cu)
6. fluorine (Fl)
7. iodine (I)
8. Manganese (Mn)
9. Molybdenum (Mo) 
10. Selenium (Se)
11. silicon
12. tin
13. Vanadium 
14. Zinc (Zn)

Major element 96 % of total 

Lesser element 3.6 % total

Trace element 0.4 % of total

Atoms 

Chemical elements are composed of units of

matter of the same type called atoms

Atoms are the smallest units of matter that

retain the properties and characteristics of

an element

Atoms are composed

of protons, neutrons,

and electrons

Atomic number and mass number  

(isotopes example 

Carbon =C 

atomic number 6 , 

mass number 12 or 13

atomic mass 12 .01

Atomic mass 

Atomic mass assumes the mass of a:

 Neutron = 1.008 daltons

 Proton = 1.007 daltons

 Electron = 0.0005 daltons

The atomic mass/weight of an element is the

average mass of all its naturally occurring

isotopes

13 

Atomic number is the number of protons in

the nucleus of an atom

Mass number is the number of protons and

neutrons in an atom

Ions, Molecules, and Compounds

Ion – an atom that has lost or gained an

electron

Molecule – 2 or more atoms sharing

electrons

Compound – a substance that can be

broken down into 2 or more different

elements

Ions, Molecules, and Compounds

Chemical bonds 

A chemical bond occurs when atoms are

held together by forces of attraction

 The number of electrons in the valence shell

determines the likelihood that an atom will form a

chemical bond with another atom

ionic Bonds

 Cat ions vs Anions 

example NaCl -chlorine 7 valence electron

sodium Na - 1 valence electron 

ionic bond in sodium chloride

single , double , triple bond 

example 

H2

O2

N2

Covalent bond - CH4, H2O

Hydrogen bond- two other associate with hydrogen atom

 

Chemical Reactions- Reactants , Product , Metabolism 

Forms of Energy & Chemical

Reaction

Energy is the capacity to do work

 Potential energy

 Kinetic energy

 Chemical energy

Law of conservation of energy

Energy Transfer 

Exergonic vs.

endergonic

reactions

Activation

energy

Type of chemical reaction 

1.Synthesis

2. Decomposition

3. Exchange

4. Reversible

5. Oxidation-reduction

Inorganic compounds usually lack carbon

and are simple molecules

•  Water is the most important and abundant inorganic compound in all living things

Organic compounds always contain H, usually contain O, and always have covalent

bonds

Water as a Polar Molecule

oxygen atoms  + hydrogen atoms =water molecule 

water as solvent 

crystals of NaCl 

Hydrated chloride ion

Hydrated sodium ion

water molecule 

water as lubricant 

Water is a major component of our body

fluids and helps reduce friction as

membranes and organs slide over one

another

Water as a Lubricant

Solutions, Colloids, and Suspensions

Mixture – a combination of elements or

compounds that are physically blended

together but not bonded together

3 types of mixtures:

1. Solution

2. Colloid

3. Suspension

Percentage of molarity

acid  HCL  (+-)

base  KOH (+- ) 

salt  KCL (+- ) 

PH Buffer (acid base ) 

Buffer system 

maintenance of body fluid homeostasis is critical 

carbon -Organic compound always contain carbon 

Many carbon can combine variety of shape

carbon compound do not dissolve in water easily 

carbon compound are good source of energy

Major functional group of organic molecules 

Hydroxyl R-O-H   alcohol contain OH group which is polar and hydrophilic molecule due to electronegative O atom (oxygen atom ) 

Sulfhydryl R-S-H  Thiols have an -SH group which is polar and Hydrophilic due to its electronegative S atom. Certain amino acid for example cysteine contain -SH group which help stabilize the shape of protein. 

 Functional group of carbon 

Major functional group of organic molecule 

     O

     ll

R- C-R  ( Ketone contain carbonyl group )within the carbon skeleton 

 

     O

     ll

R- C-H (aldehydes have a carbonyl group at the end of the carbon skeleton 

\

Major functional group of organic molecule 

Carboxyl- Carboxylic acid contain carbonyl group at the end of the carbon skeleton 

Functional group of organic molecule 

Monosaccride                                                                                                                                                

carbohydrate contain glucose 

fruit c
ontain frutose )

glactose (in milk)