Exam 3: Proteins, Carbohydrates, and Lipids

A research team tracked the carbon atoms in glucose molecules to see where they ended up when the glucose was taken up and metabolized by human cells grown in culture.The team found that 9 percent of the carbon atoms ended up in proteins.This result provides evidence for which biological function of carbohydrates in living organisms?

Refer to the figure below showing the three different oligosaccharides present on the surfaces of human red blood cells that determine blood type. Antibodies are proteins produced in the body in response to foreign substances.Antibodies recognize and bind to these foreign substances to remove them from the body.How would blood cells containing the oligosaccharide type O be received if they were transfused into the body of a patient whose own blood cells contained the oligosaccharide type A? Would the reaction be different if the reverse situation occurred; that is, blood cells containing the oligosaccharide type A transfused into a patient whose blood cells contained oligosaccharide type O? Describe the role of the oligosaccharides in these two situations.

Based on its structure, a triglyceride is most closely related to a

Sketch and label a triglyceride and a phospholipid.Write a brief comparison of the two structures.

Unsaturated fatty acids do not pack together because of the _______ in their hydrocarbon chains.

Draw a diagram of a phospholipid bilayer, and identify the hydrophobic tails and the hydrophilic heads.Where in the cell can you find such a structure?

Comparing two fatlike solid substances, you determine that sample A has a higher melting point than sample B.Sample A, therefore,

Refer to the figure showing the tertiary structure of a section of a mouse protein, and the table below, showing changes to the stability of the protein for specific single amino acid substitutions. The numbers shown in the left column refer to the amino acid's position in the polypeptide chain.Which conclusion is consistent with these data?

A student claims that all triglycerides have the exact same properties, since they are all composed of the same units: a glycerol molecule and three fatty acids.Which statement provides the best response to this claim?

Refer to the figure below. The molecules in the figure are

The monomers that make up polymeric carbohydrates like starch are called

Refer to the ribbon model of a section of polypeptide backbone in a protein. The two examples of secondary structure shown in the figure are a  pleated sheet at point A and _______ at point B.

Lipids are able to perform all of the following functions except

All carbohydrates

The amino acid sequence of a protein isolated from human blood cells is the same as the amino acid sequence of a protein isolated from chimpanzees.Which statement related to this observation is accurate?

Suppose you want to construct a protein that is 50 amino acids long.What is the theoretical number of different proteins you could make?

Complex carbohydrates are a mainstay of many diets.What are some properties that make them excellent food sources?

Refer to the figure below. Suppose you had to synthesize a phospholipid using the compound shown above as starting material.What step would you take?

A scientist isolates a previously undiscovered protein from a fruit fly and determines the sequence of amino acids making up the protein.Upon comparing the sequence to a database, he finds another protein isolated from a lizard with the same sequence.The lizard protein is known to be involved in glucose metabolism.The scientist predicts that the fruit fly protein must also be involved in glucose metabolism.How can his prediction be justified?

Refer to the table below. Based on information provided in the table, these disaccharides have different _______.