1. Macromolecules

2. The Molecules of Life Cells are made of 4 main chemical elements:
carbon, nitrogen, oxygen, and hydrogen
These atoms form 4 macromolecules they are:
carbohydrates, lipids, proteins and nucleic acids.
These molecules serve as: energy source, structural materials, metabolic workers, cell-to-cell signals, and libraries of hereditary information.

3. Life supporting molecules
Molecules that contain Carbon, Hydrogen and Oxygen in some ratio are called organic.
Macromolecules are large organic molecules.
Organic molecules are so diverse because they have carbon skeletons (backbones) that vary greatly in arrangement.
Inorganic life supporting molecules that have no specific ratio of C, H, and O
Water (H2O), Carbon Dioxide (CO2)

4. Carbon’s Bonding Behavior
Carbon’s importance in life arises from its versatile bonding behavior.
Carbon atoms can share pairs of electrons with as many as four other atoms.
Each bond is stable and strong.
Each bond joins atoms covalently into chains which form the backbones to which other elements, such as hydrogen, oxygen, and nitrogen, become attached.

5. Monomers & Polymers
Macromolecules are actually made up of even smaller subunits. Each subunit of a macromolecule is called a monomer.
The macromolecules themselves are called polymers, because they are made up of many of these subunits.
Monomer: one basic unit or subunit
Polymer: a chain of many basic units

6. Question: How Are Macromolecules Formed?

7. Answer: Dehydration Synthesis
Also called “condensation reaction” it is the combining of simple molecules to form a more complex one with the removal of water.
Forms polymers by combining monomers by “removing water”.
Dehydration
Synthesis
of a carbohydrate

8. Question: How are Macromolecules separated or digested?

9. Answer: Hydrolysis
Addition of water to a compound to SPLIT it into smaller subunits
Also called “chemical digestion”
Separates monomers by “adding water”
Hydrolysis
of a carbohydrate

10. Dehydration Synthesis of a lipid

11. Hydrolysis of a lipid

12. Dehydration Synthesis of a protein

13. Hydrolysis of a protein

14. Sugars starches and cellulose
Carbohydrates
Sugars
starches
and
cellulose

15. Carbohydrates
Living things use carbohydrates as a key source of ENERGY!
Plants use carbohydrates for structure (cellulose) not digestible by animals
Include sugars and starches
Contains the elements: carbon, hydrogen, and oxygen (in a 1:2:1 ratio) (CH2O)
Carbohydrates dissolve easily in water.
Monosaccharide is the monomer of carbohydrates.

16. Carbohydrates Monosaccharide: one sugar unit (simple sugar)
glucose
Monosaccharide:
one sugar unit (simple sugar)
All have simple ring structure
Energy for cells (provides energy for the process of respiration)
Examples:
Glucose (C6H12O6) – main source of energy for all cells
Deoxyribose - DNA
Ribose - RNA
Fructose – found in fruits and is the sweetest
Galactose – part of milk sugar (lactose)

17. Carbohydrates Disaccharide: two sugar unit Energy for cells Examples:
Sucrose (glucose+fructose) table sugar
Lactose (glucose+galactose) milk sugar
Maltose (glucose+glucose) brewing beer
glucose

18. Carbohydrates Polysaccharide:
Long chains of sugar polymers (Not sweet)
Function: energy storage, structural support
Examples:
Starch used as energy storage found in plants
glycogen (animal starch stored in liver & muscles)
cellulose (indigestible in humans – forms the cell walls of plants)
glucose
cellulose

19. Carbohydrates: Food Sources
Simple carbs (simple sugars) are found in most candy and sweet drinks, fruit, vegetables, and milk. They are quickly digested and give a short burst of energy.
Complex carbs (like starches) are found in pasta, bread, potatoes, legumes & corn. They take longer to digest, and provide energy longer.

20. Carbohydrates: Indicator Tests
Simple Sugars:
Benedict’s solution
Blue solution turns orange/green/brown
Complex Carbs:
Iodine
Turns from orange-red-brown to black-purple

21. Lipids
Fats, oils, phospholipids, and steroids – all are hydrophobic (water fearing)

22. Lipids (Fats)
Lipids are nonpolar hydrocarbons. This means they are mostly made of carbon and hydrogen with small amounts of oxygen.
Element ratio of C, H, and O: (1:2: very few)

23. Fatty Acids Fatty Acids are the monomers of lipids.
Fatty acids are unbranched carbon chains that make up most lipids.
One end is polar (hydrophilic – water loving) and the other end is nonpolar (hydrophobic – water fearing).

24. Lipids
Fatty acids are tails of fat – with1, 2, or 3 tails attached to a glycerol head.
1. Saturated fat: no double bonds (bad) solid at room temp. most animal fats:(bacon, lard, and butter) Sources of bad cholesterol are foods rich in trans fatty acids, refined carbohydrates, such as white sugar, and flour.
2. Unsaturated fat: double bonds (good) liquids at room temperature (olive oil, canola oil, Omega 3 and 6 fish oils and avocados) O
C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3 =
saturated O
C-CH2-CH2-CH2-CH
=CH-CH2-CH2-CH2-CH2-CH3 =
unsaturated

25. Lipids
Function as…
Long term energy storage: stores 2X the energy of glucose
Cushions and insulates the body and nerves.
Nerves wrapped in a lipid rich layer called: myelin sheath.
Protects against heat loss (insulation)
Structure and function - major component of cell membranes (phospholipids)
Maintain membrane structure
Through cholesterol
Hormone production
Sex hormones

26. Lipids
A triglyceride is composed of three molecules of fatty acids joined to one molecule of an alcohol glycerol.
Quantities of triglycerides are stored as droplets in the cells of body fat (adipose tissue) in every vertebrate.
Triglycerides under the skin helps penguins and some other animals survive harsh climates.

27. Lipids
Triglycerides are the body’s most abundant lipids and its richest energy source.
composed of 1 glycerol head and 3 fatty acid tails. H
H-C----O
glycerol O
C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3 = O
C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3 =
fatty acids O
C-CH2-CH2-CH2-CH
=CH-CH2-CH2-CH2-CH2-CH3 =

28. Lipids Phospholipids:
A phospholipid has two fatty acids attached to a molecule of glycerol with a phosphate group attached to the glycerol head.
They make up most of the cell membrane, which are composed of two layers of lipids.

29. Lipids
Waxes:
Waxes have long-chain fatty acids tightly packed and linked to long-chain alcohols or carbon rings.
All have a firm consistency.
All repel water.
Waxy secretions protect, lubricate, and impart pliability to skin and to hair.
Bees have beeswax, birds secrete waxes that make their feathers waterproof, aboveground plant parts are covered with waxes.
Earwax helps prevent microorganisms from entering the ear canal.

30. Sterols
Sterols:
are among many lipids with no fatty acids.
Sterols differ in the number, position, and type of their functional groups, but all have rigid backbones of four fused together carbon rings.
Eukaryotic cells have sterols in their membranes: the most common is cholesterol.
Animal hormones are made from sterols: (testosterone, estrogen and progesterone)
Cholesterol also gets remodeled into compounds such as vitamin D, steroids, and bile salts.

31. Lipids: Food Sources
As you might have guessed, fatty foods contain lipids.
Lipids are found in meat and fish, oils, avacados, eggs & nuts.

32. Lipids: Indicator Test
Paper Bag Test:
Smear substance onto paper bag
If see-thru, it contains lipids

33. Proteins

34. FUNCTIONAL GROUPS
Protein molecules contain certain groups of atoms that are attached to them, they are called functional groups.(patterns)
The carboxyl and hydroxyl groups are functional groups that define the compounds they are part of as organic acids and alcohols, respectively.

35. Proteins Amino acids is the monomer. No particular ratio of elements.
Monomers form polypeptides such as enzymes, hormones, muscles, legumes, and nuts,
Made of Oxygen, carbon, hydrogen and nitrogen
Six functions of proteins:
1. Storage - albumin (egg white)
2. Transport – hemoglobin
3. Regulatory – cyclin-regulates the cell cycle
4. Movement – muscles
5. Structural - membranes, hair, nails, horns
6. Enzymes – change the speed of cellular reactions

36. Proteins Amino Acids: 20 amino acids on the entire planet.
Each amino acid contains a central carbon atom covalently bonded to four other atoms of functional groups:
A single hydrogen atom at one site
A Carboxyl group at 2nd site (-COOH)
An amino group at 3rd site (-NH2)
And an R group at 4th site (R group differs among amino acids)

37. Proteins Dipeptides and Polypeptides:
Dipeptides are two amino acids bonded together covalently by a condensation reaction.
Polypeptides are very long chains of amino acids
Proteins are composed of one or more polypeptides.

38. Proteins
Enzymes:
Include RNA and protein molecules that act as biological catalysts.
Enzymes depend on a physical fit with a substrate (material/reactants being catalyzed).
The enzymes reacts with the substrate (material) to weakening bonds within which reduce activation energy (the energy needed to start a reaction).
After the reaction, the enzyme releases the product.
Like any catalyst, the enzyme itself is unchanged, so it can be used many times.
Temperature or pH can greatly influence the efficiency of enzymes.

39. Proteins Lock and Key Theory:
The lock is the enzyme and the key is the substrate.
Only the correctly sized key (substrate) fits into the key hole (active site) of the lock (enzyme).
Smaller keys, larger keys, or
incorrectly positioned
teeth on keys (incorrectly shaped or
sized substrate molecules) do not
fit into the lock (enzyme). Only
the correctly shaped key opens a
particular lock.

40. Proteins
Here, the disaccharide sucrose joins with an enzyme water is added and the products are:
Glucose and fructose broken apart into their simplest forms to be used by used inside the cell.

41. Nucleic Acids

42. Nucleic Acids: Structure
Nucleic Acids are made up of…
Monomers (basic unit): nucleotides
Polymers (chain of units): DNA or RNA

43. Nucleic acids Nucleotides include: phosphate group (-PO4)
pentose sugar (5-carbon)
nitrogenous bases:
adenine (A)
thymine (T) DNA only
uracil (U) RNA only
cytosine (C)
guanine (G)

44. Nucleotide O O=P-O N CH2 O C1 C4 C3 C2 Phosphate Group
Nitrogenous base
(A, G, C, or T)
CH2 O C1 C4 C3 C2 5
Sugar
(deoxyribose)

45. DNA - double helix P O 1 2 3 4 5 P O 1 2 3 4 5 G C T A

46. Nucleic Acids: Function
Stores and carries genetic information

47. Nucleic Acids: Food Sources
We get nucleic acid components from vitamins and minerals in our diet. These in turn, come from fruits, vegetables, grains, meats, & almost anything else you can think of with some nutritional value (no junk food!).

48. Nucleic Acids: Indicator Test
You will not be using an indicator test for these but in case you’re wondering…
Dische diphenylamine test (dish diphenyl + amine)
Turns from clear to light blue - dark blue if nucleic acids are present

49. Digestion & Reconstruction
When macromolecules are eaten, they are digested and broken down into their subunits (monomers).
Analogy: taking apart an old brick building
Inside the cells, these subunits are reconstructed into the structures we need.
Analogy: using bricks to build a new building

50. Digestion Products Macromolecule eaten: Broken down in stomach to:
Carbohydrates
Simple sugars (i.e. glucose)
Lipids
Fatty acids & glycerol (glycerol further broken down to glucose)
Proteins
Amino acids
Nucleic Acids
Nucleotides

51. This ppt is adapted from: cmassengale @ biologyjunction.com
The End
This ppt is adapted from: biologyjunction.com