1. A VERY Brief Overview of Chemistry
Chemistry in Biology
A VERY Brief Overview of Chemistry
15 CatchIT Questions!
Chapter 2

2. Please high-light them!!!
Words in Bold Pink
Those are your vocabulary words…
Please high-light them!!!

3. Element Element: Substance consisting entirely of one type of atom.
Examples: Carbon, Hydrogen, Oxygen

5. Elements in the Human Body
Most abundant element in our body
Oxygen – 65%
Carbon – 18.5%
Hydrogen – 9.5%
Nitrogen – 3.3%
All of these equal 96.3%. The other 4% are trace elements: Calcium (1.5), Phosphorous (1.0), Potassium (0.4), & others.
Water
Click for animation
Most abundant compound in our body

6. Subscript
A subscript is a small lowered number after a symbol for an element.
H2O– the 2 is lowered and considered
a subscript.
The 2 indicates how many atoms of the element are present in that compound.

7. Chemical Compounds
Compound: A substance formed by the chemical combination of 2 or more elements in definite proportions.
Examples: H2O (water)
NaCl (Salt)
C6 H12 O6 (Sugar)

8. Chemical Formula 6 12 6 States how many atoms are in each molecule.
How many carbon atoms are in C6 H12 O6?
How many hydrogen atoms?
How many oxygen atoms?
Click for answers 6 12 6

9. Chemical Equations CO2 + H2O -------- C6 H12 O6 + O2 REACTANTS
Let’s say I give you a chemical equation like—
CO2 + H2O C6 H12 O6 + O2
What are the names of these compounds?
Could you tell me which side are the reactants and which side are the products?
REACTANTS
PRODUCTS
Carbon
dioxide
Water
Sugar/glucose
Oxygen
Click for answers
Click for answers

10. Which of the following is an element?
CatchIT Question #1
Which of the following is an element?
Carbon dioxide
Methane
Oxygen
Water

11. How many atoms are in: NH3
CatchIT Question #2
How many atoms are in: NH3 1 2 3 4

12. Which of the following are the reactants?
CatchIT Question #3
Which of the following are the reactants?
CH4 + 2 O CO2 + 2 H2O
CH4 + 2 O2
CO2 + 2 H2O
CH4 + 2 H2O
None of the above

13. Solvent-Solute
Water is the greatest solvent in the world--the UNIVERSAL solvent!
Solvent means able to dissolve, or a dissolving agent. WATER is a SOLVENT!
Solute is what is to be dissolved. Sugar and salt are solutes and they dissolve in water.
Some substances-when dissolved in water-give the mix special properties…

15. pH pH: The measure of concentration of H+ in a solution.
Acid: Substance that release hydrogen ions (H+) when dissolved in water.
Base: Substance that releases hydroxide ions (OH-) when dissolved in water.

16. pH Scale The pH scale measures how acidic or basic a substance is.
It ranges from 0 to 14
A pH of 7 is neutral
A pH less than 7 is acidic
A pH greater than 7 is basic

17. pH Scale 14 = Basic 0 = Acidic
Oven cleaner
Bleach
Ammonia solution
Increasingly Basic
Soap
Sea water
Human blood
7 = Neutral
Neutral
Pure water
Milk
Normal
rainfall
Acid rain
Tomato juice
Increasingly Acidic
Lemon juice
Stomach acid
0 = Acidic

18. Acids
Acids taste sour
Strong Acids are dangerous and can burn your skin
Examples are: Vinegar, stomach acid, and citrus fruits

19. Bases Solutions containing bases are often called alkaline.
Bases taste bitter
Bases feel slippery
Strong bases are very dangerous and can burn your skin
Examples: Lye and ammonia

20. pH Question
An ecologist is testing rainwater. She tests rainwater on the south side of town and finds that the pH is Then she tests the north side of town and finds that the pH is Which is more acidic?
Click for answer
6.2 is correct!

21. Buffers
Buffers are weak acids or bases that can react with strong acids or bases to prevent sharp, sudden changes in pH.
Notice that these would have to be dissolved in water … having a buffer is a way to maintain homeostasis!
(Don’t need to write this)
For example, your stomach is upset, so you drink alka seltzer or eat a Rolaids. These are buffers or a mild base to offset the higher stomach acid.

22. Which of the following is a solute?
CatchIT Question #4
Which of the following is a solute?
Water
Sugar
Vinegar
Carbon dioxide

23. Which of the following has the most basic pH?
CatchIT Question #5
Which of the following has the most basic pH? 7
7.1
7.5 8

24. CatchIT Question #6
3.1 pH is:
Acidic
Basic
Neutral
None of the above

25. Gastric protease works best in which type of pH?
CatchIT Question #7
Gastric protease works best in which type of pH?
Neutral
Basic
Acidic
All of the above

26. Which of the following is a solvent?
CatchIT Question #8
Which of the following is a solvent?
Water
Sugar
Vinegar
Carbon dioxide

27. Organic Molecules There are 4 organic molecules Carbohydrates Lipids
Proteins
Nucleic Acids
* These are also called macromolecules

28. Macromolecule Concept Map
4 Types of Carbon
Compounds
Contain the elements
Contain the elements
Contain the elements
Contain the elements
built with
built with
built with
built with
Function in
Function in
Function in
Function in
What does Macro Mean?

29. ***Most of an organisms’ energy come from carbohydrates!***
Carbohydrate: Organic compound containing Carbon, Hydrogen, & Oxygen with a ratio of 1:2:1
Carbohydrates are basically sugars and starches.
***Most of an organisms’ energy come from carbohydrates!***

30. Carbohydrates Continued
Monosaccharides are simple sugar molecules.
Examples: This is glucose, galactose, sucrose and fructose (sugars).
Glucose is
1 : 2 : 1
Many monosaccharides together make up polysaccharides. This is the excess sugar that we store as glycogen that can turn into fat
Glucose = most COMMON monosaccharide

31. Macromolecule Concept Map
Lets fill in the chart!
Macromolecule Concept Map
4 Types of Carbon
Compounds
Carbohydrates
Contain the elements
Contain the elements
Contain the elements
Contain the elements
1-C: 2-H :1-O
built with
built with
built with
built with
Monosaccharides
(glucose)
Function in
Function in
Function in
Function in
Quick energy for cells
What does Macro Mean?

32. Lipids This is FAT. They are found in cell membranes.
Lipids: these are used to store energy.
They are found in cell membranes.
Fats, oils, & waxes
Also water proofs

33. What does Macro Mean? Macromolecule Concept Map
Lets fill in the chart!
Macromolecule Concept Map
4 Types of Carbon
Compounds
Lipids
Carbohydrates
Contain the elements
Contain the elements
Contain the elements
Contain the elements
1-C: 2-H :1-O
C, H, a little O
built with
built with
built with
built with
(fats/oils)
Monosaccharides
(glucose)
Function in
Function in
Function in
Function in
Quick energy for cells
Stores energy long term & water proofs
What does Macro Mean?

34. Nucleic Acids
Made up of Carbon, Hydrogen, Oxygen, Nitrogen, & Phosphorus
Nucleic acids store and transmit hereditary or genetic information.

35. Nucleic Acids Continued
Nucleotides consist of a 5 carbon sugar, a phosphate group and a nitrogen base.
2 types: Deoxyribonucleic Acid (DNA)
& Ribonucleic Acid (RNA)

36. What does Macro Mean? Macromolecule Concept Map
Lets fill in the chart!
Macromolecule Concept Map
4 Types of Carbon
Compounds
Nucleic Acids
Lipids
Carbohydrates
Contain the elements
Contain the elements
Contain the elements
Contain the elements
1-C: 2-H :1-O
C, H, a little O
C, H, O, N, P
built with
built with
built with
built with
(fats/oils)
nucleotides
Monosaccharides
(glucose)
Function in
Function in
Function in
Function in
Genes/
Heredity
Quick energy for cells
Stores energy long term & water proofs
What does Macro Mean?

37. Which of the following is NOT a macromolecule?
CatchIT Question #9
Which of the following is NOT a macromolecule?
Carbohydrate
Lipid
Amino acid
Nucleic acid

38. Which of the following foods is NOT an example of a carbohydrate?
CatchIT Question #10
Which of the following foods is NOT an example of a carbohydrate?
Sugar
Potatoes
Bread
Meat

39. Genetic material is made with this macromolecule:
CatchIT Question #11
Genetic material is made with this macromolecule:
Nucleic acid
Lipid
Protein
Carbohydrate

40. Which of the following is NOT a sugar?
CatchIT Question #12
Which of the following is NOT a sugar?
a. Glucose
b. Sucrose
c. Lactose
d. Pepsin

41. Proteins Proteins are composed of smaller units called amino acids.
Amino Acids: Are small compounds that are made of carbon, nitrogen, oxygen, and hydrogen.
Amino Acids are
monomers of proteins

42. Proteins
Activation Energy: The minimum amount of energy needed for reactants to form products in a chemical reactions.

43. Proteins
A catalyst, as well as an enzyme, is a substance that lowers the activation energy needed to start a chemical reaction.
* Catalysts speed up chemical reactions thousands of times faster.

44. Example: Amylase found in saliva.
Proteins
Enzymes are biological catalysts that speed up the rate of chemical reactions.
* Enzymes are made of proteins.
Example: Amylase found in saliva.
Amylase speeds up the breakdown of amylose, a substance in starch (in foods).
* Most enzymes are specific to 1 reaction

45. Proteins: How enzymes work
Substrate: The reactants that bind to the enzyme.
Active Site: The specific location where a substance binds to an enzyme.
* The active site and the substrate have complementary shapes (“Lock & Key”)
Click on picture to see an animation!

46. Proteins: How enzymes work
Only substrates with the same size and shape as the active site will bind to the enzyme (like puzzle pieces).
pH and temperature mainly affect enzyme activity.
Click on picture for link

47. How about a little animation?
Enzyme-Substrate Relationship
Yet another enzyme animation...Get it yet?

48. Pepsin: An Enzyme Pepsin is an enzyme in the
stomach that begins the digestion
of proteins by splitting them into
smaller pieces.
Pepsin works at a pH level of around 2 which is acidic
Antacids are used to neutralize pepsin by increasing the pH level to around 6 or 7

49. What does Macro Mean? Macromolecule Concept Map
Lets fill in the chart!
Macromolecule Concept Map
4 Types of Carbon
Compounds
Nucleic Acids
Lipids
Proteins
Carbohydrates
Contain the elements
Contain the elements
Contain the elements
Contain the elements
1-C: 2-H :1-O
C, H, a little O
C, H, O, N, P
C, H, O, N, S
built with
built with
built with
built with
Amino acids
(fats/oils)
nucleotides
Monosaccharides
(glucose)
Function in
Function in
Function in
Function in
Genes/
Heredity
Quick energy for cells
Stores energy long term & water proofs
Growth/ enzymes
What does Macro Mean?

50. Enzymes are which type of macromolecule?
CatchIT Question #13
Enzymes are which type of macromolecule?
a. Lipids
b. Carbohydrate
c. Proteins
d. Nucleic Acids

51. What do enzymes do during a reaction?
CatchIT Question #14
What do enzymes do during a reaction?
a. Nothing
b. Slows it down
c. Speeds it up
d. Burns it up

52. What two conditions change how enzymes work?
CatchIT Question #15
What two conditions change how enzymes work?
a. Water & temperature
b. Temperature & pH
c. Solid & gas
d. None of the above

53. The End