Carbohydrates (Mid 1)

Question 1

Which of the differences listed here could be found among molecules of the same monosaccharide (e.g. differences that could be seen between two glucose molecules)? (Choose all that apply)

Multiple answers:
Multiple answers are accepted for this question

a
a difference in the position of the carbonyl (C=O) group in the linear form

b
a difference in the number of carbons

c
a difference in the overall shape of the molecule − one is a ring and the other is linear

d
a difference in the orientation of a hydroxyl (-OH) group in the linear form

e
a difference in the orientation of a hydroxyl (-OH) group in the ring form

Answer 1

c
a difference in the overall shape of the molecule − one is a ring and the other is linear
e
a difference in the orientation of a hydroxyl (-OH) group in the ring form

Question 2

Galactosemia is a potentially fatal disease that occurs in humans who lack the enzyme that converts galactose to glucose. If you were a physician treating a person with this disease, which of the following would be most important to have them exclude from their diet?

a
Milk

b
Beer

c
Bread

d
Candy

e
Fruit

Answer 2

a
Milk

Question 3

Lysozyme, an enzyme found in human saliva, tears, and other secretions, breaks the β-1,4-glycosidic linkages in peptidoglycan. Predict the effect of this enzyme on bacteria.

a
Lysozymes would cause the destruction of bacteria by causing the breakdown of carbohydrates into their individual atoms, providing a first layer of protection.

b
The peptidoglycan in bacterial cell walls begins to degrade, leading to the death of the bacteria and protecting humans against bacterial infections.

c
Lysozymes would promote the formation of cell walls by linking adjacent monomers, ensuring maintenance of healthy bacteria.

d
The peptidoglycan would be converted to starch, providing fuel for the bacteria, causing them to grow, and potentially causing bacterial transfer from one organ to another.

Answer 3

b
The peptidoglycan in bacterial cell walls begins to degrade, leading to the death of the bacteria and protecting humans against bacterial infections.

Question 4

cellulose is nearly identical in many ways to starch; however, we cannot digest cellulose. Why?

a
Cellulose molecules have their monosaccharides arranged differently

b
Cellulose molecules are form fewer hydrogen bonds

c
Cellulose molecules are form helical instead of linear shapes

d
Cellulose molecules lack carbon-hydrogen bonds

e
Cellulose molecules are formed entirely from fructose

Answer 4

a
Cellulose molecules have their monosaccharides arranged differently

Question 5

During the process of mammalian fertilization, a sperm cell encounters glycoproteins in the gelatinous extracellular matrix that surrounds the ovum. Experimental removal of the carbohydrates from these glycoproteins prevents fertilization. Which carbohydrate function is demonstrated by these results?

a
Structural support

b
Energy storage

c
Cell identity

d
All of the above

e
None of the above

Answer 5

c
Cell identity