This document summarizes key concepts about biology and chemistry of life. It discusses the elements that make up living matter like carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. It also describes the four major macromolecules - carbohydrates, lipids, proteins and nucleic acids - that make up all cells. Carbohydrates, lipids and proteins are described in terms of their structure, composition and functions. Nucleic acids DNA and RNA are discussed in terms of their nucleotide monomers and how they link together. Absorption mechanisms like facilitative transport and active transport are also mentioned.

1. BIOLOGY:
• CHEMISTRY OF LIFE
• Presentation by D.T Nyalunga
• University of johannesburg, 2012

2. Element
An element is a substance that cannot be
broken down to other substances by
ordinary chemical means.
98% of living matter is made of
Carbon
Hydrogen
Nitrogen
Oxygen
Phosphorus
Sulfur

4.  Molecules of life are synthesized by living cells
 Carbohydrates
 Lipids
 Proteins
 Nucleic acids (madel, 2009)

5. What are the 4 major macromolecules that make up
all cells?
Carbohydrates Lipids
Proteins Nucleic
Acids

6.  Consist primarily of carbon and hydrogen
atoms
 Carbon atoms bond covalently with up to four other
atoms, often in long chains or rings
 Functional groups attach to a carbon backbone
 Influence organic compound’s properties

7. Carbohydrates - sugars
• Carbohydrates are made up of monomers call
monosaccharide (one sugar)
• carbo-: sounds like carbon
• -hydrate: means something combined with
water
• General formula for carbohydrates: CnH2nOn

8. (Sharafeddin, 2010)

10.  Three main types of carbohydrates
 Monosaccharides (simple sugars)
 Oligosaccharides (short chains)
 Polysaccharides (complex carbohydrates)
 Carbohydrate functions
 Instant energy sources
 Transportable or storable forms of energy
 Structural materials

11. (http://learn.genetics.utah.edu/content/begin/cells/sc

13.  Lipids
 Fats, phospholipids, waxes, and sterols
 Don’t dissolve in water
 Dissolve in nonpolar substances (other lipids)
 Lipid functions
 Major sources of energy
 Structural materials
 Used in cell membranes

15. (williamson, 2010)

18. Nucleic Acids – DNA/RNA
• Nucleic acids are made of monomers called
nucleotides
• Nucleotides link together by dehydration reactions
(JessicaSandel, 2011)

19. Nucleic Acids – DNA/RNA
• Each Nucleotide has 3 main parts

20. Absorption of Carbohydrates & Amino acids
Two main mechanisms of absorption :
1-facilitative transport ; with the gradient
2- active transport ; against the gradient .

21. Bibliography
 http://learn.genetics.utah.edu/content/begin/cells/scale. (n.d.).
 JessicaSandel. (2011). molecule of life. chicago.
 madel, c. (2009). molecule of life. u.k.
 Sharafeddin, O. (2010). absorption of amino acids and carbohydrates. u.k.
 williamson, J. (2010). Molecule of life. johannesburg: Pearson international.