1) A strong signal at 1700 cm–1 in an IR spectrum indicates the presence of a(n) a. alcohol b. ether c. carbonyl d. amine 2) A strong signal at 3400 cm–1 in an IR spectrum indicates the presence of a(n) a. alcohol b. ether c. carbonyl d. amine

1) c. carbonyl 2) a. alcohol (hydroxyl)

The difference of two numbers is 2, and their sum is 16. What are the two numbers?

Let "a" and "b" be the two numbers. 1) a - b = 2 2) a + b = 16 To solve, get one variable alone on either side of the equation: equation 1) can be written as so: a = 2 + b Now, plug in this new value for "a" into equation 2) (2 + b) + b = 16 or 2 + b + b = 16 Combine like variables by adding them together 2 + 2b = 16 Subtract 2 from each side: 2b = 14 Now, divide by 2 on each side to solve for b. b = 7 To get a, we can now plug in the value we found for b. a = 2 + b a = 2 + 7 a = 9 Therefore, the answer is: a = 9, b = 7

Describe the molecular structure of hemoglobin.

Hemoglobin is a red-pigmented protein that transports oxygen and CO2. When blood is maximally loaded with oxygen, it is termed oxygenated (bright red). When some oxygen is lost and CO2 is gained during systemic cellular gas exchange, blood is deoxygenated (dark red) -Each hemoglobin molecule contains four protein molecules called globins. Two of these globins are called alpha chains, and other two, which are slightly different, called beta chains. All globin chains contain a heme group, which is composed of porphyrin ring, with an iron ion in its center. Oxygen binds to Fe2+ in heme groups for transport in blood.