1. Unit 2 Part 1: Organic Compounds (Biomolecules) and Enzymes

2. Organic Compounds
Contain Carbon atoms that are covalently bonded together usually with Hydrogen (H), Oxygen (O), and Nitrogen (N)
Found in all living things

3. Carbon Has 4 electrons in outermost shell Can form 4 covalent bonds
Can make straight chains, branched chains, or rings
Can form single, double,
or triple bonds
Leads to lots of variety

4. Chemical Reactions
Bonds between atoms are built and broken causing substances to combine and recombine as different molecules during chemical reactions.
All of the chemical reactions within a cell are referred to as the cell’s metabolism.

5. Large Carbon Molecules
Monomers are
building blocks of organic molecules
small, simple molecules that can be put together to make larger molecules called polymers.
Large polymers
macromolecules
made of repeated chains of monomers

6. Making Polymers Dehydration (synthesis) reaction
Monomers link together to form polymers
Water is removed to bond the monomers together
Monomer + Monomer Polymer + Water

7. Breaking Down Polymers
Hydrolysis reaction
Polymers are broken down back into monomers
Water is added to break the bond between monomers
Polymer + Water Monomer + Monomer

8. Molecules of Life
4 main types of organic compounds are essential to life in all living things
Carbohydrates
Proteins
Lipids (fats)
Nucleic Acids

9. Carbohydrates Made of C, H and O in a 1:2:1 ratio
Used as energy in cells
Monosaccharide (simple sugar)
Glucose, fructose, galactose
Disaccharides (double sugars)
2 monosaccharides put together
Sucrose = fructose + glucose

10. Carbs Cont.
Polysaccharide is a complex molecule composed of three or more monosaccharides.
Glycogen stores energy
Starch
Cellulose makes plants rigid

11. Role of Carbohydrates Functions Energy Source
Glucose in cells is the primary source of energy fuel for cellular respiration
Energy Storage (short term)
Glycogen in the liver of animals
Starch in the structures of plants
Structural Support
Cellulose forms cell walls in plants
Also an important source of fiber for animals to stimulate the digestive system

12. Role of Carbohydrates In Plants In Animals
Carbohydrates are synthesized during the process of photosynthesis
The plants then:
Use them as a source of energy
Store them in the cells.
In Animals
Carbohydrates are consumed as sugars, starches, and fiber
Digestion breaks the bonds between the larger carbohydrate molecules so that individual simple sugars
Simple sugars can be absorbed into the bloodstream through the walls of the intestines.
Once inside the cells, simple sugars are used as fuel in the process of cellular respiration, releasing energy which is stored as ATP.
If an organism has a greater supply of carbohydrates than needed for its energy requirements, the extra energy is converted to fats and stored by the body.

13. Proteins Proteins are organic compounds made mainly of C, H, N, O
Amino Acids are the monomers of proteins
There are 20 different amino acids
11 amino acids are made in the human body
Humans need to consume the other 9 amino acids from sources such as nuts, beans, or meat (these are essential amino acids)

14. Proteins cont. Each amino acid contains a central carbon atom
covalently bonded to
four other atoms or
functional groups.

15. Proteins Cont.
A very long chain of amino acids is called a polypeptide.
Proteins are composed of one or more polypeptides in 3D shapes.
Protein shape can be denatured by conditions such as temperature or pH. If the shape changes the protein will not work correctly.

16. Roll of Proteins
Proteins are more important as a source of building blocks than as a source of energy. Proteins can function as an energy source only if there is a shortage of carbohydrates or lipids.
Because of their structures, proteins serve different functions.
Structural: connective tissue, hair, nails (keratin)
Transport: hemoglobin transports oxygen
Hormone: insulin to regulate sugar levels
Contractile: help control muscle movement
Enzymatic: accelerate body functions (digestion)

17. Enzymes Enzymes are proteins that act as catalysts.
Catalysts speed up the rate of a reaction or allow a reaction to take place.
The enzyme and the substrate have shapes that allow them to fit together like a lock and key.
The enzyme and substrate bond at an active site
The enzyme is unchanged by the reaction and can be used again.

18. Lipids
Large, nonpolar, organic molecules that do not dissolve in water
Like carbohydrates, Lipids also contain Carbon, Hydrogen, and Oxygen
Lipids store energy and are energy rich due to number of C-H bonds
Fatty Acids are the monomers of lipids
three fatty acids
glycerol

19. Saturated and Unsaturated Fats
Each carbon atom is covalently bonded to four atoms
Found in animals
Are solid at room temp
Unsaturated fat
Carbon atoms that form double bonds
Found in plants
Are liquid (oils) at room temp

20. Types of Lipids Phospholipids Wax Steroids Form cell membranes
Waterproof and form a protective coating
Steroids
Many animal hormones are steroids
Cholesterol: needed by the body for nerve cells and other cells to function normally

21. Role of Lipids
Fats are important to organisms for energy when carbohydrates are scarce, but when there is no shortage of food, stored fat accumulates.
Functions
Energy Storage (long-term)
Animals in colder climates will store more fats to use as insulation as well as energy to keep warm
Stored fats are also used to cushion vital organs
Cellular Membrane Structure
A major component of the cell membrane is the phospholipid
Building Vitamins and Hormones
These help regulate our metabolism

22. Nucleic Acids 5 carbon sugar nitrogen base phosphate group
store and transmit genetic information in the cell.
Contain H, O, N, C, and P
Monomers = nucleotides
Nucleotide has three parts
5 carbon sugar
nitrogen base
phosphate group
Types:
RNA or Ribonucleic acid
DNA or Deoxyribonucleic acid

23. Nucleic Acids cont. Function Store information
DNA – holds genetic code for an organism
RNA – makes a copy of DNA in order to make a protein