Chapter Review

1-12, 14 & 15

1.Which of the following is not an organic molecule?
C. Water
2. Which of the following terms includes al the other terms on this list?
D. Glycogen is used in carbohydrates, used in monosaccharides used is polysaccharides
3. Which term is the most appropriate to describe a molecule that dissolves easily in water?
C. hydrophilic
4.Cholesterol is an example of what kind of molecule?
B. Lipid
5. The 20 amino acids vary only in their...
B. Side group
6. A specific reactant an enzyme act upon is called the...
D. Substrate
7. An enzyme does which of the following?
B. Lowers the activation energy of a reaction
8. Besides satisfying your hunger why else might you consume a big bowl of pasta the night before a race?
Pasta is a carbohydrate used for energy, also why athletes would eat toast, though normally a protein is eaten with it so the energy lasts longer.
9. How are glucose sucrose and starch related? Starch is made of glucose and sucrose is made of the same things as glucose but in a different format.
10. What are steroids? Describe 2 functions they have in cells. A steroid is a lipid molecule in which the carbon skeleton forms 4 fused rings, they can produce other steroids and are used in cell membranes.
11.How are polypeptides related to proteins? Proteins are made by linking amino acids into a chain called a polypeptide.
12.How does denaturation affect the ability of a protein to function? The process of denaturation unravels the protein so that it cannot function.
14. A.H2O
B. A dehydration reaction, a water molecule is removed to connect 2 molecules
C. On the very left and the left bottom
15. A. Around 38 for enzyme A and 78 for enzyme B
B. Enzyme A is found in humans because the other needs more heat therefor is heat loving
C. Because the reaction starts at that temperature and is just giving off temperature after that

5.5

Enzymes are proteins that speed up specific reactions in cells:

• Activation energy is the energy needed to start a chemical reaction
• Catalysts can start a chemical reaction by giving activation energy without destroying the cells
• A main catalyst is enzymes
• the enzyme doesn't actually start the reaction it just lowers the temperature needed so that it happens on its own
• Enzymes work on substrates : A specific reactant
• and the area in the enzyme the reaction occurs is the active site
• another way this may work is that it holds the reactants together until they react
  

Concept Check:
1. Explain the role of activation energy. How does an enzyme affect this?
Activation energy allows a chemical reaction to take place and enzyme lowers the energy needed to start the reaction
2.Describe how a substrate interacts with an enzyme.
The substrate is a reactant that goes into the active site

5.4

Proteins Preform most functions in Cells:

• A protein is a polymer of just 2o kinds of monomers
• they are responsible for most day to day functioning organisms
• Proteins also defend the body from harmful microorganisms
• Amino acids are monomers with a central carbon bonded to 4 partners
• one partner must be a hydrogen atom 2 others are carboxyl group and the rest are amino groups
• the differences in amino acids are the side groups that attach to the fourth bond or the "R" group
• A polypeptide are amino acids linked in chains each link is made by the dehydration reaction
• the body can make many varieties of proteins
• Protein shape are precisely made and influenced by its surroundings
  
• during an unfavorable change in pH the protein will unravel, this is denaturation

Concept Check:
1.Give 2 examples of proteins you can see in the world around you, what are their functions?
Proteins make hair grow, and muscle is protein.
2.Relate amino acids, polypeptides and proteins.
Amino acids make up polypeptides and proteins
3. Explain how heat can destroy a protein.
Heat can make it unravel therefore destroying it
4.Which parts of an amino acid is the same in all amino acids? What is unique?
All have a hydrogen bond and a carboxyl group the rest is unique

Summarization 5.3

Lipids Include fats and steroids:

• Oil cannot mix with water due to lipids
• Water avoiding molecules are hydrophobic
• Lipids act as boundaries for water to your cells
• a fat is a 3-carbon backbone called glycerol attached to 3 fatty acids that have long hydrocarbon chains
• Fat stores energy for later use
• A saturated fat is a fat that contains the most hydrogen atoms possible
• an unsaturated fat is a fat with at least 1 less possible than the max hydrogen atom
• A lipid molecule that the carbon skeleton forms 4 rings is a steroid
• Steroids all have 4 rings but the positioning affect the type of steroid it is
• Steroids are hydrophobic
• Cholesterol is a steroid that is found in the membranes of your cells
• only a certain type of cholesterol is bad

Concept Check:
1. What properties do lipids share?
Lipids are all hydrophobic
2. What are the parts of a fat molecule?
A 3 carbon backbone and 3 fatty acids with long hydro carbon chains
3. Describe 2 ways that steroids differ from fats.
Steroids circulate the body as chemical signatures, and structure is different
4. What does the term unsaturated fat on a food label mean?
Unsaturated means that it doesn't have the most possible water molecules it could have

Summarization 5.2

Carbohydrates provide fuel and building material:

• Carbs used to provide energy
• A carbohydrate is an organic compound made up of sugar molecules
• Sugars contain a ratio of 1 carbon 2 hydrogen and 1 oxygen
• Carbon Skeletons have a ring shape
• Simple sugars are monosaccharides
• Sugar molecules particularly glucose are the main fuel supply for cellular work
• Disaccharides are double sugars(2 monosaccharides)
  Polysaccharides are long polymer chains made of simple sugars
• Excess sugar is stored with a polysaccharide called glycogen
• When the body needs energy it breaks down this glycogen for glucose
• The polysaccharide cellulose protect cells and stiffen plants preventing it from "flopping over"
• Cellulose is fiber, passes unchanged through your digestive system
• This keeps you healthy but is not a nutrient.
• Almost all carbohydrates are hydrophillic.

Concept Check:

1. Explain the differance between a Monosaccharide and a Disaccharide. Give an example of each. The differance between a monosaccharide and a disaccharide is that a monosaccharide has just 1 sugar unit while a disaccharide has 2. 1 monosaccharide is Glucose, a disaccharide is sucrose.
2. Compare and contrast starch, glycogen, and cellulose. All are polysaccharides, found in plants and have glucose monomers.
3. How do animals store excess glucose molecules? Animals store excess glucose molecules through starch

Summarization 5.1

Carbon is the main ingredient of organic molecules:

• Life can't exist without carbon
• Carbon produces carbon skeletons & functional groups
• Organic & inorganic molecules
• Organic has carbon inorganic does not
• carbon bonds with many elements eg. carbon & hydrogen = hydrocarbons
• Carbon skeletons attach to functional groups
• Monomers & polymers produce bio molecules
• all living cells have thousands of polymers
• Large molecules: lipids, carbohydrates, proteins, nucleic acid
• Building & breaking polymers- Dehydration reaction
• Dehydration reaction is: a monomer is added to a chain and a water molecule is released
• Breaking down- break by adding water

Concept check:

1. C3H8O
2. Explain the connection between monomers and polymers. Polymers are made of monomers
3. What molecule is released during construction of a polymer? What is this reaction called? A water molecule is released during the construction of a polymer it is the dehydration reaction
4. Draw three ways 5 carbon atoms could be joined to make different carbon skeletons.

A water molecule

A picture of a molecule

A picture of an atom