IB Biology
N. Cunningham/J. Chen
Student Note Packet
I. Chs. 4 & 5 Carbon and Organic Molecules
(Why are carbon compounds key to the variety of life?)
A.
Introduction
1. The four major classes of organic compounds in living systems
a.
b.
c.
d.
2. In addition to carbon, what other elements are included in organic
compounds?
B.
Organic chemistry
1. Define the term organic molecule.
2. State whether the following compounds are organic or inorganic:
a. CO2 _______________
b. CH4 _______________
c. H20 _______________
d. C6H12O6 __________
3. Vitalism
a. Defined?
b. How can it be tested?
c.
C.
How was urea used to disprove vitalism?
Carbon atoms are the most versatile building blocks of molecules.
1.Refer to the electron configuration of carbon, and explain how
many bonds carbon will form.
2. Define the term hydrocarbon and give an example.
3.Which organic molecule found in living systems has hydrocarbon tails?
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4. Complete the following chart.
Butane
Molecular formula
Similarity
Isobutane
Difference
5. Define the term isomer.
6. The chemical elements of life: a review
a. What are the six major elements that make up living matter?
b. What kinds of bonds join these elements in living matter?
c. How many covalent bonds does carbon form?
D.
Ch.5 – Macromolecules Introduction
1. What is a macromolecule?
2. What are the 4 major classes of macromolecules?
3. Define the term polymer.
4. What is a monomer?
5. Define dehydration synthesis (condensation reaction).
6. How is water produced as a result of this process?
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7. The process requires…?
8. Why is dehydration synthesis considered an anabolic reaction? (How will
you remember?)
9. Define the term hydrolysis.
10. What life process is associated with hydrolysis?
11. Why is hydrolysis considered catabolism?
Review
1. What reaction does the diagram to the right
represent?
2. Which molecule represents a monomer?
3. Which molecules represent polymers?
4. What is the source of the H and OH on molecules
C and D?
5. What is the opposite reaction to this one?
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E.
CARBOHYDRATES
1. What elements make up carbohydrates?
2. Ratio of H to 0 in carbohydrates?
3. Carbohydrates are categorized by size
a. Monosaccharides
b. Disaccharides
c. Polysaccharides
4.Sugars, the smallest carbohydrates, serve as a source of energy
a. Which carbohydrates are the major fuels for cellular work?
b How can you recognize a carbohydrate by its molecular formula?
c How can you recognize carbohydrates by their name?
d. List 3 monosaccharides?
1.
2.
3.
e. How are monosaccharides classified?
f. What word can be used to describe glucose, galactose and fructose? Why?
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5. Draw the molecular structure of a glucose molecule in the space below:
6. If carbohydrates have multiple –OH groups, will they tend to be hydrophilic or
hydrophobic? Why?
7. Will simple sugars tend to dissolve in water? Why or why not?
8. What is a disaccharide?
a. Maltose 
b. Sucrose
c.
Lactose
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9. Use what you know to figure out the molecular formula for
a. Maltose
b. Sucrose
10.
Review:
1. Maltose
2. Sucrose
3. Lactose
Match the disaccharide with the monosaccharides that form each.
A. Glucose + galactose
B. Glucose + glucose
C. Glucose + fructose
Match the disaccharide with the
descriptions.
1. Transports energy in the phloem of
plants
2. Provides energy to baby mammals
3. Has the molecular formula C12H22O11
11. Polysaccharides
a. What are they?
b. Functions?
i.
ii.
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A. Maltose
B. Sucrose
C. Lactose
c. Plant polysaccharides include STARCH and CELLULOSE:
i. STARCH- (Function?)
____________ glucose
molecules link to form
starch.
ii. Contrast amylose with amylopectin?
iii. How is an alpha glucose different from a beta glucose molecule?
iv. Starch is made of repeating ______________________________while cellulose
is made of repeating ____________________________________.
____________ glucose
molecules link to form
cellulose.
v. What is the function of cellulose?
iv. What value does eating a vegetarian diet serve with
respect to the human digestive system?
d. Animal polysaccharides include GLYCOGEN and CHITIN:
i. GLYCOGEN
Structure?
Identify what kind of glucose is found in glycogen. (alpha or beta?) Explain
how you know.
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Function?
ii. CHITIN =
Structure?
Functions?
Match the term with its description or definition.
1. Used in insect exoskeletons & fungus cell walls
A. Chitin
2. Coiled structure
B. Cellulose
3. Used in plant cell walls
C. Glycogen
4. Energy storage molecule in plants
D. Starch/ Amylose
5. Energy storage molecule in animals
6. Contains alpha 1-4 glycosidic linkages
F.
LIPIDS
1. Examples of lipids?
2. Unifying feature of lipids?
3. Elements in lipids? Ratio?
4. A Fat (triacylglycerol or triglyceride) is one example of a lipid.
a. Building blocks : 1 ___________+
3 ______________ 1 fat + ________water
5. Functions of fat?
6. The hydroxyl group is found in glycerol.
a. What elements make up this group? Draw it.
b. What properties does this group impart to glycerol?
c. How will I remember glycerol’s molecular structure?
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7. What functional group is found in organic acids like fatty acids?
a. Draw it.
b. What properties does this group impart to fatty acids? Why?
8. How will I remember a fatty acid’s molecular structure?
9. How does the process of dehydration synthesis construct fats?
10. Why are fats hydrophobic?
11. What bond joins fatty acids to glycerol?
12. How can fatty acids differ?
Saturated Fatty Acids
C to C bonds
(single? double?)
Unsaturated Fatty Acids
Mono
Poly 
Hydrogen at every
possible position on the
carbon chain?
Shape (straight or
kinked)?
Sources?
Solid or liquid at room
temp?
Examples?
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13. Draw a saturated fatty acid.
14. Distinguish between a fat and a fatty acid.
15. What is a hydrogenated oil?
16. What is a trans fatty acid and why is it unhealthy to eat fats containing trans
fatty acids?
Match the term with its description or definition
1. Contains more than one carbon-carbon double bonds
2. Contains carboxyl group
3. All carbon atoms in the chain connected by single bonds
4. Bent molecule that releases H+ ions in solution
5. Straight acidic molecule
6. Contains one carbon-carbon double bond
17. Major functions of fats in living organisms?
1.
2.
3.
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A. Saturated fatty acid
B. Polyunsaturated fatty acid
C. Monounsaturated fatty
acid
D. Trans unsaturated fatty
acid
E. Cis unsaturated fatty acid
18. Fats vs. Carbohydrates for Energy Storage in Humans
Energy?
Carbohydrates
Fats
17 kJ (4kcal) of energy
released per gram
38 kJ (9kcal) of energy
released per gram
Efficiency for energy
storage?
Ease in building up and
breaking down
19. Explain why starch is a polymer and triglyceride is not.
20. Phospholipids, found in cell membranes are another example of a lipid.
a. Structure?
i.
ii.
iii.
b. Why is the presence of a phosphate group important to a
phospholipid’s behavior?
c. Why do phospholipids have a double personality  Amphipathic
d. How do phospholipids interact with water?
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e. How are phospholipids adapted to function as part of the cell
membrane?
21. Steroids , another type of lipid, include cholesterol and certain hormones.
a. Structure?
b. Why is cholesterol such an important example of a steroid?
i.
Positive attribute?
ii.
Negative attribute?
Lipid Review
 True or False: All lipids are fats.
 What are the three components that are attached to a glycerol molecule in a
phospholipid?

Sketch a diagram of a phospholipid. Where are these found in a cell?

Describe the structure of a steroid.
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
G.
Why is cholesterol such an important steroid?
PROTEINS
1. Proteins are instrumental in about everything an organism does. This is
because proteins have so many functions including:




2. See chart below:
3. Proteome?
4. Protein building blocks =
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5. Polymers of amino acids =
What is the relationship between a protein and a polypeptide?
6. Draw a picture of an amino acid here:
7. What makes all amino acids the same?
8. What makes the 20 different amino acids different?
9. Circle and label the amino group in your drawing from #5.
Also, explain what properties an amino group confers to all amino acids.
10. Similar to fatty acids, amino acids have a carboxyl group. Circle and label the
carboxyl group in your drawing from #5.
What properties does this functional group confer to amino acids?
11. The 3 types of R groups in amino acids are ___________________,
_________________________, and, ________________________________.
12. Find the sulfhydryl group (-SH) in the list of amino acids.
Why is the presence of this group important to some proteins?
13. Amino acids are joined together when dehydration synthesis occurs. What
kind of bond is formed between adjacent amino acids? __________________________
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Circle or
highlight all
the peptide
bonds.
14. Draw 2 amino acids and then show the condensation/dehydration synthesis
reaction to form a dipeptide and water.
15. Repeated dehydration synthesis over and over creates__________________________
Circle the peptide bonds on the
polypeptide.
16.
R
e
v
i
Review about amino acids
a. How are all amino acids the same?
b. How are amino acids different?
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c. How can living organisms build such a large variety of polypeptides?
H.
Proteins are 3D!
1. Examples of how protein structure is adapted to function:
a. Antibodies –
b. Neurotransmitters –
c. Enzymes -
2. Primary structure =
3. Change in primary structure 
Example?
4. Secondary structure=
a. Examples:
b. What kinds of bonds hold the secondary
structure in place? What part of the
polypeptide strand is involved?
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5. Tertiary structure =
a. What holds tertiary structure together?
6. Quaternary structure=
a. Examples?
 Fibrous

Globular 
7. Why is hemoglobin considered a conjugated protein?
8. How does the primary structure determine the folding pattern seen in the
tertiary and quaternary structures? How do all these levels of structure
determine the ultimate structure and function of all proteins?
Protein Structure Review
1. Results from H bonds at regular intervals along the
polypeptide backbone
A. Primary structure
2. The sequence of amino acids
B. Secondary structure
3. the union of two or more polypeptide subunits
C. Tertiary structure
4. Determined by H bonds, ionic bonds & hydrophobic
interactions
D. Quaternary structure
5. Alpha helix & pleated sheet
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9. A protein can unravel or denature in response to changes in physical and
chemical conditions.
a. What conditions cause denaturation?
b. Why do proteins denature?
c. How do proteins denature?
4321
10. What is metabolism?
I. ENZYMES ARE PROTEINS
1. Enzymes are catalysts 
2. Enzymes are not consumed
3. If enzymes are proteins, then why are they all different shapes?
4. What do enzymes do to activation energy?
5. Why don’t enzymes affect delta G of a reaction?
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6. Enzymes are substrate specific
a. Substrate =
Enzyme+SubstrateEnzyme Substrate Complexproduct
b. Example?
c. Active site?
d. LOCK AND KEY HYPOTHESIS =
e. INDUCED FIT HYPOTHESIS (more accepted theory) =
7. Enzymes have complex shapes that determine their function! (primary-secondarytertiary –quaternary)
a. The active site’s shape and chemistry determines how the reaction will
proceed.
b. Role of amino acid R groups at the active
site?
c. Are enzymes changed by the reaction?
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8. Enzyme activity is affected by certain factors.
a. SUBSTRATE CONCENTRATION:
Why is the graph showing an increase initially?
Why does the graph eventually level off?
b. TEMPERATURE:
Every enzyme has an optimal temperature at which it works.
What happens at low temperatures?
What happens at high temperatures?
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c. pH – Every enzyme has an optimal pH at which it works.
What happens at high and low
pH values for most enzymes?
d. How do variations in salt concentration affect enzyme activity?
e. Cofactors
1. What are they?
2. Examples?
9. Metabolic pathways consist of chains or cycles of enzyme catalyzed reactions.
Sometimes the end
product of a series
of chemical
reactions can
“feedback” to the
initial reaction and
inhibit it.
https://www.studyblue.com/notes/note/
n/microbial-metabolism-/deck/10602
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I. Control over enzyme action.
1. INHIBITORS can also regulate enzyme reactions
a. Competitive inhibitors=
b. How can carbon monoxide be lethal?
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c. NONCOMPETITIVE INHIBITORS =
2. What is an allosteric enzyme (protein?)
3. Explain how enzymes are involved in keeping
homeostasis using the diagram to the right.
4. State 5 factors that affect the activity of enzymes.





(Try review questions on the PowerPoint slideshow)
5. What is an “immobilized” enzyme?
6. How is immobilized lactase enzyme used to produce
of lactose-free milk?
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K. NUCLEIC ACIDS – Another organic compound that is fundamental to life
1. Types of nucleic acids?
a.
b.
2. What is ATP?
3. What are some functions of DNA and RNA and ATP in the cell?
4. Building blocks of nucleic acids=
a. Sugarb. Phosphate –
c. Nitrogen base –
3. How does the presence of a phosphate group in nucleic acids impact their
properties?
4. Nitrogen bases fall into two categories:
PURINES
PYRIMIDINES
EXAMPLES?
# Rings?
Remember: Thy-Cy-Py
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5. How is the sugar deoxyribose in DNA different from the sugar ribose in RNA
and ATP?
6. Draw the pentose sugar ribose:
7. What kinds of bonds results when nucleotides go through condensation
(dehydration) synthesis reactions? Describe this bond.
8. What is formed as a result of repeated dehydration /condensation synthesis
reactions involving nucleotides?
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9. Circle 2 more nucleotides in the diagram below. Then draw and label a simple
diagram of a nucleotide.
Dehydration
synthesis
(condensation)
reactions link
nucleotides
together.
10. Similarities and differences between DNA and RNA
List at least 3 similarities:
Complete the chart to contrast DNA and RNA in three ways.
Characteristic
DNA
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RNA