1. Quiz 4) Which of the following bonds makes a water molecule polar?
A) polar covalent bonds between H and O
B) covalent bonds between C and O
C) hydrogen bonds between ammonia and water
D) electrical attraction between H and O
5) The property of water that allows it to stick to chemicals is:
adhesion/cohesion
Phase changes/ 3 states
Specific heat
Ice floats

2. Unit 2 quiz resumes Tuesday: 2.2, Homework: Reading: 2.3
Updates:
Water case study due
pH lab due
Unit 2 quiz resumes Tuesday: 2.2,
Homework:
Reading: 2.3

3. Quiz
6. The ability of water molecules to store large amounts of energy in their hydrogen bond networks is called:
Specific heat
Adhesion
Surface tension
Cohesion
7. Which of the following solutions has the most H ions (protons) “hopping” into solution?
pH of 6
pH of 8
pH of 7
pH of 4

4. LEQ: What distinguishes living chemistry in nature?
Activator:
Keystone writing prompt (type 1)
Attempt at least 1 line per section
No penalty for incorrect answers
No notebooks!
Key terms – lipid, monomer, polymer, carbohydrate,

5. Carbon atoms foster complexity and organization.
Carbon has special bonding properties
can covalently bond with up to four other atoms:
C…HNOPS
Carbon is the central atom of biological chemistry. This atom is uniquely suited to form up to four single covalent bonds. These bonds are stable, share electrons equally with many different elements, and are long-lasting.
Its versatility in forming different arrangements is also unrivaled in biological chemistry. Carbon can easily bond with itself to form straight chains, branching patterns, and even ring structures that add surface area and occupy space in biological molecules. This arrangement in molecular structure will suit a unique biological function .

6. Biomolecule
Monomer or basic components
Polymer or types
Function(s)
Looks like?
Carbohydrate
Nucleic acid
Protein
Lipid

7. The functions of lipids are as diverse as their chemistry.
Lipids (fats): C-H bonds; generally nonpolar
Triglycerides contain fatty acids (yellow) bonded to a sugar alcohol (gray) to store energy
Lipids are characterized as generally nonpolar and hydrophobic molecules. They tend to be very rich in C-C bonds which share electrons equally between atoms. Weak charges similar to water occur infrequently in this type of molecule.
Unlike our previous biomolecules, lipids do not polymerize. They do have functional regions that lend them certain chemical properties such as the fatty acid tails shown above in yellow. They are characterized by a number of C-C and C-H bonds, which are very nonpolar.

8. The various fats and oils in plants and animals consist of lipids of many different types. One of the most notable differences in their chemistry is the arrangement of covalent bonds in fatty acid tails.
The lipid on the left consists of three fatty acid tails that are saturated. This means that each carbon atom has single covalent bonds around it allowing each fatty acid to pack closely to adjacent fatty acids making aggregates very dense and solid at room temperature.
Double bonds can create bends in a fatty acid tail preventing adjacent fatty acid tails from packing to close together. We say that a tail with at least one double bond is unsaturated and aggregates of unsaturated lipids tend to behave as a liquid at room temperature.

9. Video Discussion: Trans Fats
What are some foods that you eat that contain trans fats?
Why are trans fats so bad for you?
Why has the food industry used trans fats in the past?
What are some substitutes to trans fats that you think the food industry could begin using?

10. Cholesterol is a steroid; used to make hormones and cell membranes
Cholesterol is a type of lipid, but unlike any lipid we have seen thus far. You might think that it has more in common with a monosaccharide or nucleotide because of the ring-shaped central structure, but that is where the similarity stops. Notice anything missing? No nitrogen, and a single oxygen atom shown – this molecule is extremely non polar.
Cholesterol is one example of a type of lipid called a steroid. Cholesterol is an essential component of any animal’s diet because it is required to build cell membranes and synthesize certain types of hormones.

11. Phospholipids have polar “heads” and nonpolar “tails”
Hydrophilic head
Phosphate
Glycerol
Our last lipid for this lesson is probably the most unique molecule we have seen thus far. Phospholipids are unique because they consist of a chemistry that is both polar and nonpolar across the molecule! The hydrophilic head region consists of a phosphate group (charged) and normally has some type of additional combination of carbon and nitrogen or oxygen permitting some hydrogen bonding to take place. The fatty acid tails can be either saturated or unsaturated. The hydrophobic tails pack close together in water and readily layer in a characteristic fashion to form layered bubbles.
Fatty acids
Hydrophobic tails
Hydrophilic
head
Hydrophobic
tails
(a)
Structural formula
(b)
Space-filling model
(c)
Phospholipid symbol

12. Focus: the hydrophobic effect

14. Water article questions, last call Unit 2 quiz resumes today: 2.2
Updates:
2.2 study guide due
Water article questions, last call
Unit 2 quiz resumes today: 2.2
Homework:
Reading: 2.3
quiz continues tomorrow review 2.3

15. Quiz
6. The ability of water molecules to store large amounts of energy in their hydrogen bond networks is called:
Specific heat
Adhesion
Surface tension
Cohesion
7. Which of the following solutions has the most H ions (protons) “hopping” into solution?
pH of 6
pH of 8
pH of 7
pH of 4

16. LEQ: What distinguishes living chemistry in nature?
Activator:
Review your water article from yesterday.
By yourself: choose your favorite point or quote from the text that illustrates why water is important to life.
Briefly, explain why you chose this part of the reading
Key terms – monomer, polymer, carbohydrate,

17. Biomolecule
Monomer or basic components
Polymer or types
Function(s)
Looks like?
Carbohydrate
Nucleic acid
Protein
Lipid

18. Carbohydrates have roles in energy storage and cellular structure:
Polymer: polysaccharide
Monomer: monosaccharide
Carbohydrates are biomolecules that have roles in energy storage and forming cellular structures such as cell walls in some organisms such as plants and fungi. Each monomer is called a monosaccharide and a common carbohydrate monomer, glucose is shown above. Note all that oxygen, this molecule is very polar and will readily dissolve in water (hydrophilic).

19. Task: build a molecule of glucose and fructose
Modeling:
Task: build a molecule of glucose and fructose
Which way is the hydrogen and –OH oriented?
Carbohydrates are biomolecules that have roles in energy storage and forming cellular structures such as cell walls in some organisms such as plants and fungi. Each monomer is called a monosaccharide and a common carbohydrate monomer, glucose is shown above. Note all that oxygen, this molecule is very polar and will readily dissolve in water (hydrophilic).

20. All macromolecules are constructed from a few simpler compounds.
Monomers individual subunits (various types)
Polymers are made of many monomers.
Biomolecules are molecules that are made or consumed by biological organisms.
Certain molecules have the potential to store information; meaning that because the molecule is assembled by ordering subunits together in acharacteristic fashion, a meaning can be associated with it.
This idea is easy to understand , if you consider how a word is constructed. A word consists of different letters put together in characteristic sequence. Change the sequence of the letters changes the meaning and appearance of the word.
The letters in the biological alphabet are called monomers and the assemblage of this alphabet is called a polymer. Each biomolecule that is also a polymer has its own unique chemical language. We’ll consider the monomeric alphabet of carbohydrates next.

21. Example: dehydration/condensation reactions make polymers

22. Example: Hydrolysis of a polymer

23. Starch (plants) and glycogen (animals) store energy
Cellulose is an essential structure for plant cell walls

25. Video Discussion: Secrets in the Salt
Why were the scientists so excited about the discovery of cellulose in the salt layer?
Where would you find cellulose today?
What evidence for conditions on Earth (even before the time of the dinosaurs) do you find most convincing? Interesting? Explain.

26. Summary:
What are the four main classes of macromolecules?
Which include polymers?
What is the relationship between a polymer and monomer?
Explain how both nucleic acids and proteins are polymers. Be sure to describe the monomers that make up the polymers.
How are carbohydrates and lipids similar? How are they different?
Explain how the bonding properties of carbon atoms result in the large variety of carbon-based molecules in living things.