1. Biological Molecules
Part 2

2. Review of Reactions Condensation/Dehydration/Synthesis
Monomers joined together
One monomer releases H+, the other releases OH-
Hydrolysis Reaction
Polymers broken down
required
H+ joins one , OH- joins other

3. Dehydration reactions

4. Not Dehydration

5. Cells contain four major families of small carbon-based organic molecules
covalent bonds between the building block monomers create polymeric macromolecules
3:3

7. Proteins
Large molecules ( ) that form some of the cytoplasm, hormones, globulins, antibodies, and
Provides structure (ex: and cartilage)
Composed of group (NH2) group (COOH) and a common attached to the side chain R
R group can be one H or as complex as a system

8. R groups
amino acids in total
All have different R groups

9. Proteins
Amino acids joined together through reactions (water produced) to form polymer and .
Polypeptide chains can be between 50 – amino acids long are referred to as .
During the dehydration reaction, a bond forms between N of group of one amino acid and the C of the group of the other amino acid
The peptide bond is (slightly positive H and slightly negative O)

10. Formation of Peptide Bond

11. Proteins Primary structure Secondary structure
Amino acid sequence of a chain (a single linear chain of amino acids)
Secondary structure
Amino acids within the polypeptide chain begins to form H-bonds
H-bonds cause the chain to either form a , a sheet, loops, or turns within the same chain

12. Proteins

13. Tertiary structure
The different structures within the polypeptide chain come together and arrange themselves to form a shape due to different non-covalent interactions (H- bonding, ionic interactions, van der waals forces, and interactions)
Once this globular shape is finalized, covalent bonds form between two (S-S) in different R groups to the proteins shape together

15. Quantenary Structure More than one chain comes together to form this
many, although not all engage in this type of structure

17. hemoglobin
each red blood cell contains ~3x108
hemoglobin molecules

18. Proteins
Tertiary structures can be changed or denatured by heat, , UV light or pH.
Denaturation can be temporary or
What is denaturation?
Function loss due to structure change

19. Carbohydrates Can be classified as monosaccharides, disaccharides, and
have carbon chains between 3-7 C’s in length
Ex) 3C monosaccharides = triose
4C monosaccharides = pentose
6C monosaccharides =
Two monosaccharides joined together through reactions form a
A disaccharide can be broken down through to form two
Polysaccharides are long chains of
Ex) cellulose or starch

21. Carbohydrates

22. Monosaccharides form disaccharides
3:9

23. Basic Photosynthesis
Works hand in hand with cellular respiration

24. Glucose monomers linked by glycosidic bonds form storage carbohydrates
starch in plants
glycogen in animals
polysaccharides
Polysaccharides also play an important role in cell structure and cell signaling
3:10

26. Polysaccarides Glycogen Starch Cellulose Made up of monomers
Makes up the cell
in plant cells No
Made up of glucose monomers
Glucose is stored in this form in animal cells
Can be into glucose monomers if need for cellular
Extensive branching
Made up of glucose monomers
Glucose is stored in this form in plant cells
Can be hydrolysed into glucose monomers if need for cellular respiration
branching glycogen

27. Lipids

28. Lipids - Triglyceride contains C, H, and O no fixed ratio of atoms
ex: fats and oils
found in cell
also used for storage
all have two separate building blocks:
1) 1 glycerol 2) 3 fatty acids
* 3 fatty acids and one glycerol make 1 lipid molecule

29. Lipids Oils: liquids at room temperature many bonds in fatty acids
Fats:
solid at room
fewer bonds
Waxes:
at room temperature
longer carbon backbones 15

30. Lipids
H from each OH of glycerol joins with OH from carboxyl group of each fatty acid through a reaction
Results in the formation of (neutral fat) + 3H2O
Glycerol

33. Saturated vs. Unsaturated

35. Lipids-Phospholipid Phospholipids Lipid with a group
Usually a neutral fat with a phosphate on one of the fatty
Found in cell (phospholipid bilayer)
Polar end in high water concentration area cytoplasm or fluid

36. Phospholipids
3:12

37. Hydrophilic Molecules
2:17

38. Hydrophobic molecules
Nonpolar molecules and nonpolar portions of molecules tend to
aggregate in water =
Water cannot form hydrogen bonds with nonpolar substances
Water will form hydrogen bonds with other water molecules and surround a nonpolar molecule
The less hydrophobic surface, the more energetically favorable it is for water to surround nonpolar molecules
How is this accomplished?
By nonpolar molecules aggregating
C-C and C-H bonds are the most common nonpolar bonds in biological systems
2:18

39. Hydrophobic Effect
2:19
Hydrophobic effect is not an attraction between particles but an avoidance of an energetically unfavorable state

40. Hydrophobic effect
2:20

41. A lipid bilayer prevents the diffusion of polar substances
solutes spontaneously diffuse from a region of high concentration to a region of low concentration
a lipid bilayer prevents the diffusion of polar substances out of the inner compartment (also prevents the inward diffusion of polar substances)
3:13

42. Types of Lipids steroids: 1. : 2. hormones:
1. :
a. component of cell membranes that affects stiffness
b. to synthesize other steroids/hormones
e.g. testosterone & estrogen
2. hormones:
growth/functioning of specific cells
chemical messengers between cells
e.g. stimulates sperm production

43. Nucleic Acids
Purines Pyriminadines
Cytosine
Adenine

44. Nucleic Acids Are formed of subunits called
Nucleotide are composed of a base, a sugar, and a acid
In DNA the nitrogenous base may be one of 4: – adenine, guanine
Pyrimidines – ,

45. DNA
DNA (Deoxyribonucleic Acid) is sided with H-bonds between the bases holding it together
Purines have two bonds between them while have three hydrogen bonds

46. RNA RNA (Ribonucleic acid) is stranded
RNA contains the base instead of thymine

47. ATP
ATP (Adenosine Triphosphate) is a containing an adenine, a ribose sugar, and groups (instead of one)
Between each phosphate group are rich bonds
This is where the cell obtains its
ATP ADP + phosphate + energy

48. By the end of this section you should know:
Demonstrate knowledge of dehydration synthesis and hydrolysis as applied to organic monomers and polymers
Differentiate among carbohydrates, lipids, proteins, and nucleic acids with respect to chemical structure
Recognize the following molecules in structural diagrams: ATP, DNA, disaccharide, glucose, glycerol, hemoglobin, monosaccharide, neutral fat, phospholipids, polysaccharide (starch, glycogen, and cellulose), ribose, RNA, saturated and unsaturated fatty acids, steroids
Recoginze the empiracle formula of a monosaccharide as CnH2nOn
List the main functions of carbohydrates
differentiate among monosaccharides (e.g., glucose), disaccharides (e.g., maltose), and polysaccharides
differentiate among starch, cellulose, and glycogen with respect to: function, type of bonding, level of branching
describe the location, structure, and function of the following in the human body: neutral fats, steroids, and phospholipids

49. compare saturated and unsaturated fatty acids in terms of molecular structure
list the major functions of proteins
draw a generalized amino acid and identify the amine, acid (carboxyl), and R-groups
identify the peptide bonds in dipeptides and polypeptides
differentiate among the following levels of protein organization with respect to structure and types of bonding: primary, secondary (alpha helix, beta pleated sheet), tertiary, quaternary (e.g., hemoglobin)
list the major functions of nucleic acids (RNA and DNA)
name the four nitrogenous bases in ribonucleic acid (RNA) and describe the structure of RNA using the following terms: nucleotide (ribose, phosphate, nitrogenous base, adenine, uracil, cytosine, guanine), linear, single stranded, sugar-phosphate backbone
name the four nitrogenous bases in DNA and describe the structure of DNA using the following terms: nucleotide (deoxyribose, phosphate, nitrogenous base, adenine, thymine, cytosine, guanine), complementary base pairing, double helix, hydrogen bonding, sugar-phosphate backbone
compare the general structural composition of DNA and RNA
relate the general structure of the ATP molecule to its role as the “energy currency” of cells