1. The chemistry of organic molecules Professor: Zied Jezawi
Biology: lecture one
The chemistry of organic molecules
Professor: Zied Jezawi

3. What is the organic molecules
The chemistry of organisms.
Another definition: the molecules that contain both carbon and hydrogen atoms.
Inorganic molecules
Organic molecules
Usually contain +ve and –ve ions
Always contain carbon and hydrogen
Usually ionic bonding
Usually covenant bonding
Always contain a small number of atoms
Often quite large with many atoms
Often associated with nonliving matter
Usually associated with living organisms

4. The carbon skeleton and functional groups
The carbon chain of an organic molecules is called: skeleton or backbone (R group).

5. What is the (R) group
It is the carbon tail of molecule and regards as inactive part… so it has no function in chemical reactions.

6. Functional group
It is a specific combination of bonded atoms that always reacts in the same way, regardless of the particular carbon skeleton and give the molecule its distinct properties. OH
Carbon chain or
(R) group
Hydroxyl group or
Alcoholic group
Butanol

8. carbohydrates
An organic compounds comprising only carbon, hydrogen and oxygen… e.g.- sugar, starch.

9. Carbohydrates properties
1- used as an immediate energy source in organisms. 2- play structural roles in organisms. 3- the majority of carbohydrates have carbon to hydrogen to oxygen ratio of 1:2:1. 4- there are two types of carbohydrates according to the number of structural units: Polymers and monemers.

10. Monosaccharaides
Consisting of only a single sugar molecule and have a carbon backbone of three to seven carbons (multiple of CH2O).

11. Disaccharide
Contain two Monosaccharaides that have joined during a dehydration reaction.

12. Starch: stores in plants
Polysaccharides
It is a Polymers of Monosaccharaide. The function: 1- short-term energy storage molecules 2- structural functions
Starch: stores in plants

13. Glycogen: stores in muscle and liver/ source of direct energy
Cellulose: form a structural fibers in plants/human can not digest those fibers

14. lipids
In general lipids are Compounds that not soluble in water due to their hydrocarbon chain.

15. Triglycerides
Fats and oil contain two types of subunit molecules: fatty acid and glycerol.

16. phospholipids
Lipids that contain phosphate group and have hydrophilic head and hydrophobic tail.
Plasma cell membrane consist primarily of a phospholipids bilayer.

17. steroids
Kind of lipids have skeletons of four fused carbon rings.

18. Cholesterol
Type of steroids that is an essential component of animal cells.
May contribute to circulatory disorders.
Cholesterol accumulation

19. Waxes Long-chain fatty acids bond with long chain alcohols.
Waxes form a protective cuticle in plants.

20. proteins Polymers of amino acid monomers.
Proteins role: metabolism, support, transport, defense, regulation and motion.

22. DNA and RNA
DNA consists of three main elements: 1- nitrogen bases (Adenine “A” Thymine “T” Guanine “G” Cytosine “C”). 2- phosphate group. 3- deoxy-pentose sugar. Or (deoxy-ribose sugar).

23. RNA RNA has the same structure of DNA except:
1- RNA has oxy-pentose sugar.
2- RNA has uracil (U)nitrogen base instead of thymine (T).

24. Appendix of terminology
Organic molecules: المركبات العضوية
Organism: الكائن الحي
Atom: ذرة
Ionic bonding: الرابطة الايونية
Chain: سلسلة
Inactive: غير فعال
Reaction: التفاعل
Functional group: المجموعة الوظيفية
Distinct: مميز
Features: خصائص
Properties: مميزات
Starch: النشا

25. Mono: أحادي
Di: ثنائي
Poly: متعدد
Dehydration: عملية نزع جزيء ماء لتكوين روابط كيميائية
Short-term: مدة قصيرة
Long-term: مدة طويلة
Soluble: ذائب
Hydrophilic: محب للماء
Hydrophobic: كاره للماء
Bilayer: ثنائي الطبقات
Essential: أساسي
Circulatory system: الجهاز الدوراني
Disorders: إعتلالات
Metabolism: عملية الأيض
Motion: الحركة
Regulation: التنظيم

26. Test Your Self إختبر نفسك

27. 1- Which of the following is considered a macromolecule?
A) Nucleic acid
B) Amino acid
C) Fatty acid
D) None of the above
2- Which of the following is NOT one of the classes of primary organic molecules?
A) Carbohydrates
B) Proteins
C) Salts
D) Nucleic acids
3- The process by which polymers are turned into monomers is called__________.
A) dehydration synthesis
B) ionization
C) hydrolysis
D) phagocytosis

28. 4- The molecule that stores the information about the order of amino acids in a protein is _____.
A) ATP
B) RNA
C) DNA
5- The three-dimensional shape of a polypeptide is associated with its _____.
A) primary structure
B) secondary structure
C) tertiary structure
D) quaternary structure
The nucleotide that supplies energy for dehydration synthesis is _____.
A) adenosine triphosphate
B) guanine
C) thymine
D) cytosine 6-

29. 7- The two strands of DNA are held together by _____ between the purine and pyrimidine bases.
A) ionic bonds
B) hydrogen bonds
C) covalent bonds
8- The bond between two amino acids is ______.
A) formed by hydrolysis
B) an ionic bond
C) nonpolar
D) know as a peptide bond
9- Dieticians recommend that the majority of our dietary calories come from ______.
A) saturated fats
B) proteins
C) carbohydrates
D) cholesterol

30. 10- After hydrolysis of a triglyceride, we would have _____.
A) many amino acids
B) different types of nucleotides
C) fatty acids and glycerol
D) monosaccharides and disaccharides
11- Which is the INCORRECT association between monomer and polymer?
A) monosaccharide - polysaccharide
B) nucleic acid - polypeptide
C) nucleotide - nucleic acid
D) amino acid - polypeptide
12- One would expect in the structure of a DNA molecule thymine would always be paired to ________.
A) uracil
B) adenine
C) guanine
D) cytosine

31. 13- Each nucleotide's structure should have all of the following except:
A) Sugar
B) Nitrogenous base
C) Phosphate group
D) Amine group
14- The action of disrupting the three-dimensional shape of a protein is termed _______.
A) dehydration
B) denaturation
C) deamination
D) hydrolysis
15- Fats which have one or more double bonds within their fatty acid tails are labeled as _____ fats.
A) saturated
B) waxy
C) unsaturated
D) greasy

32. 16- Polysaccharides, the complex carbohydrates, break down into reduced/simple sugars during which of the following processes?
A) Hydrolysis
B) Osmosis
C) Dehydration synthesis
D) Electron transport
17- All of the following are functional benefits of the body's fat stores except ________.
A) membrane structural material
B) enzyme action
C) insulation
D) a rich energy source
18- To which group of organic compounds do both DNA and RNA belong?
A) Amino acids
B) Fatty acids
C) Nucleic acids
D) None of these answers

33. Which statement best describe the behavior of carbon?
A) Carbon can share pairs of electrons with two other atoms.
B) Carbon can share pairs of electrons with as many as six other atoms.
C) Carbon can lose up to three atoms.
D) Carbon can share pairs of electrons with as many as four other atoms.
20- Complex carbohydrates are stored in animals in the form of
A) Cellulose
B) Glycerol
C) Glycogen
D) Lactose
19-

34. Thank You