1. Chemistry Of Cells

2. Chemistry
Science that studies the elements, their compounds, the chemical reactions that occur between them and the molecular structure of all matter

3. Matter Anything that takes up space and has mass
Everything we touch is matter
Three forms
Solid
Liquid
Gas

4. Elements
Substances that can’t be broken down into another substance by ordinary chemical means
All matter, living and non-living composed of elements
92% naturally occurring elements
Differ by properties

5. Our Elements Six elements special to us Make up 98% of our body weight
C- carbon
H- hydrogen
N- nitrogen
O- oxygen
P- phosphorus
S- sulfur
Make up 98% of our body weight

6. Atomic Theory
Elements consist of tiny particles called atoms- smallest particle of an element that displays the properties of the element

7. Atomic Structure Three types of subatomic particles
Neutrons- no electrical charge
Protons- positive charge
Electrons- negatively charge
Nucleus- center of the atom
Protons and neutrons located within
Electrons (e-) move about nucleus

9. Periodic Table
Developed as a way to display elements according to their characteristics

10. Understanding Chemical Bonds
Atoms most stable when outer shell is full
Octet rule- outer shell containing 8 electrons

11. Compounds
Substance composed of atoms of two or more elements that are chemically combined
Example: NaCl (table salt)
Compounds form when elements try to comply to the octet rule

12. Types of Bonds
Ionic- forms when 2 atoms are held together by attraction between opposite charges
Ions- charged atoms
Often form salts
Example: Na+ Cl-

13. Types of Bonds
Covalent- two atoms share electrons in order to have completed outer shell
Example: oxygen gas (O2)
Molecule- group of atoms held together by covalent bonds

14. Bonds Single bond- when two atoms share a single electron
Double bond- when each atom shares two electrons
Triple bond- when each atom shares three electrons

16. Chemical Reactions
Occur when bonds are formed or broken causing substances to recombine into different substances
Metabolism- all chemical reactions occurring in the cells of organisms
Written as follows:

17. Mixtures and solutions
Mixture- combination of substances in which individual components retain their own properties
Example: mixing sand and sugar
Solution- mixture in which one or more substances (solutes) are distributed evenly in another substance (solvent)
Example: adding sugar to ice tea

18. Acids and Bases Acids- substances that dissociate in water
Release hydrogen ions (H+)
Example: HCl-hydrochloric acid (stomach)
Base- substances that take up hydrogen (H+) ions or release hydroxide (OH-) ions
Example: NaOH- sodium hydroxide

19. pH and Its Scale
pH- way of indicating the number of hydrogen ions in solutions
pH scale- used to indicate acidity or basicity of solutions
Ranges from 0 to 14
7 is neutral
pH < 7= acid
pH > 7= base
Buffer- chemical that keeps pH within normal limits (example- Tums and Rolaids)

21. Water’s Importance to Life
Life began in water
Single most important molecule on Earth
Cells are 60-80% water
Polar molecule- molecule with an unequal distribution of charge
Each molecule has a positive end and negative end
Unique properties

22. Another Type of Bond
Hydrogen (H)- weak bond, arises between slightly positive hydrogen atom of one molecule and slightly negative atoms of another molecule
Example: H2O
Water molecules attract other water molecules

23. Properties of Water Because of H-bonds Properties
Can engage in 4 H-bonds
Properties
Solvency
Cohesion and adhesion
High surface tension
High heat capacity
High heat of vaporization

24. Life Substances Carbon has 4 electrons available for bonding
To be stable it forms 4 covalent bonds
Can bond with other carbons or with many other elements
Form straight chains, branched chains, or rings
Can have almost any number of carbons
Can form different structure (shapes)
Isomer- compounds with same chemical formula but different 3-d structures

26. Carbohydrates
Biomolecule composed of carbon, hydrogen and oxygen (1:2:1 ratio)
Monosaccharide- simplest type of carb (sugar)
Glucose and fructose
Disaccharide- combining of two monosaccharides
Glucose and fructose link together to form sucrose

27. Carbohydrate cont’d
Polysaccharide- largest, composed of many monosaccharides
Starch- branched, energy storage
Glycogen- highly branched, stores energy in liver
Cellulose- long chains (like chain link fenece), forms cell walls of plants and gives them support

28. Carbohydrates cont’d Five- and six-carbon simple sugars are smallest
Five-carbon: deoxyribose and ribose
Six-carbon: glucose and fructose
Functions: energy storage and cell structure

29. Lipids Insoluble in water 95% of fats in body are triacylglycerols
Saturated fat: fatty acids have single covalent bonds
Unsaturated fat: fatty acids have one or more double covalent bonds
Functions: energy, insulation and protection

30. Proteins Contain carbon, oxygen, hydrogen, nitrogen and sulfur
Amino acids are building blocks of proteins
Functions: energy and structure
Enzymes: protein catalysts for chemical reactions

31. Proteins Structure Primary: amino acid sequence
Secondary: determined by hydrogen bonds
Tertiary: folding caused by interactions within peptide bonds and sulfur atoms
Quaternary: determined by spatial relationships between units

32. Nucleic Acids
Deoxyribonucleic acid: genetic material of the cell (DNA)
Ribonucleic acid: protein synthesis
Messenger RNA
Transfer RNA
Structure
DNA: double helical chain
RNA: single chain

33. Nucleic Acids Nucleic acids are made up of chains of nucleotides
Nucleotide: nitrogen base, sugar and phosphate group
Nitrogen bases: purines (two) and pyrimidines (three)

34. Adenosine Triphosphate
ATP
Fuel for cell function and maintenance
Molecule consists of sugar, adenine, and three phosphates
Energy is stored in the second and third phosphates
Breakdown of glucose provides energy to make ATP

36. Enzyme Protein that changes rate of chemical reactions
Involved in nearly all metabolic processes
Speed reactions in digestion of food
Activities of enzymes depend on temp, ionic conditions, and pH of surroundings