Carbohydrates

For each of the following, give the monosaccharide units produced by hydrolysis, the type of glycosidic bond, and the name of the disaccharide including $\alpha$or $\beta$ :

For each of the following, give the monosaccharide units produced by hydrolysis, the type of glycosidic bond, and the name of the disaccharide including $\alpha$or $\beta$:

Indicate whether each disaccharide in the problem $13.41$is a reducing sugar or not.

Describe the similarities and differences in the following:

a. amylose and amylopectin

b. amylopectin and glycogen

Describe the similarities and differences in the following:

a. amylose and cellulose

b. cellulose and glycogen

Give the name of one or more polysaccharides that matches each of the following descriptions:

a. not digestible by humans

b. the storage form of carbohydrates in plants

c. contains only $\alpha (1\to 4)$-glycosidic bonds

d. the most highly branched polysaccharide

Give the name of one or more polysaccharides that matches each of the following descriptions:

a. the storage form of carbohydrates in animals

b. contains only $\beta (1\to 4)$-glycosidic bonds

c. contains both $alpha(1\to 4)$ - and $alpha(1\to 6)$-glycosidic bonds

d. produces maltose during digestion

The next day. Kate had 1 cup of cereal $(15 g$ carbohydrate) with skim milk$(7 g$ carbohydrate). 1 banana $( 17 g$ carbohydrate). and $\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.$ cup of orange juice ( $12 \mathrm{g}$ carbohydrate) for breakfast.

a. Has Kate remained within the limit of $45$ to $60 \mathrm{g}$of carbohydrate?

b. Using the energy value of $4 kcal/g$ for carbohydrate, calculate the total kilocalories from carbohydrates in Kate's breakfast, rounded to the tens place.

Kate's blood volume is $3.9 L$. Before treatment, if her blood glucose was $178\mathrm{mg}/\mathrm{dL}$, how many grams of glucose were in her blood?

Kate's blood volume is $3.9 \mathrm{L}$. After three months of diet and exercise, if her blood glucose is $146\mathrm{mg}/\mathrm{dL}$, how many grams of glucose are in her blood?

For breakfast, Kate had $1$ cup of orange juice $(23 \mathrm{g}$ carbohydrate), $2$ slices of wheat toast ( $24 \mathrm{g}$ carbohydrate), $2$ tablespoons of grape jam ( $26 \mathrm{g}$ carbohydrate), and coffee with sugar substitute ( $0 \mathrm{g}$ carbohydrate).

a. Has Kate remained within the limit of $45$ to $60 \mathrm{g}$ of carbohydrate?

b. Using the energy value of $4\mathrm{kcal}/\mathrm{g}$ for carbohydrate, calculate the total kilocalories from carbohydrates in Kate's breakfast, rounded to the tens place.

Isomaltose, obtained from the breakdown of starch, has the following Haworth structure; 

a. Is isomaltose a mono-d- or polysaccharide?

b. What are the monosaccharides in isomaltose?

c. What is the glycosidic link in isomaltose?

d. Is this the $\alpha$ or $\beta$ isomer of isomaltose?

e. Is isomaltose a reducing sugar?

 Sophorose, a carbohydrate found in certain types of beans, has the following Haworth structure: 

a. Is sophorose a mono-, di-, or polysaccharide?

b. What are the monosaccharides in sophorose?

c. What is the glycosidic link in sophorose?

d. Is this the $\alpha$ or $\beta$ isomer of sophorose?

e. Is sophorose a reducing sugar?

Melezitose, a carbohydrate secreted by insects, has the following Haworth structure: $(13.4,13.5,13.6)$

a. Is melezitose a mono-, di-, or trisaccharide?

b. What monosaccharides are present in melezitose?

c. Is melezitose a reducing sugar?

Identify the chiral carbons if any in each  of the following compounds: 13.2

Raffinose, found in Australian manna and in cottonseed meal, has the following Haworth structure: 

$(13.4,13.5,13.6)$

a. Is raffinose a mono-, di-, or trisaccharide?

b. What monosaccharides are present in raffinose?

c. Is raffinose a reducing sugar?

What are the disaccharides and polysaccharides present in each of the following? (13.6,13.7)

(a)

(b)

What are the disaccharides and polysaccharides present in each of the following? (13.6,13.7)

Gentiobiose is found in saffron. $(13.4,13.5,13.6)$

a. Gentiobiose contains two glucose molecules linked by a $\beta (1\to 6)$-glycosidic bond. Draw the Haworth structure for $\beta$-gentiobiose.

b. Is gentiobiose a reducing sugar? Explain.

If $\alpha \mathit{-}$galactose is dissolved in water,$\beta \mathit{-}$galactose is eventually present. Explain how this occurs. (13.5)

D-Erythritol is $70\%$ as sweet as sucrose and contains only hydroxyl functional groups. When D-erythritol is oxidized it forms D-erythrose. Draw the Fischer projection for D-erythritol. $(13.3,13.5)$

D-Sorbitol, a sweetener found in seaweed and berries, contains only hydroxyl functional groups. When D-sorbitol is oxidized, it forms D-glucose. Draw the Fischer projection for D-sorbitol. $(13.3,13.5)$

 What are the differences in the Fischer projections of D-glucose and D-fructose? (13.3)

What are the differences in the Fischer projections of D-galactose and L-galactose? (13.3)

The sugar D-gulose is a sweet-tasting syrup. (13.3, 13.4)

a. Draw the Fischer projection for L-gulose.

b. Draw the Haworth structures for  $\alpha$- and $\beta$-D-gulose.

Identify each of the following pairs of Fischer projections as enantiomers or identical compounds: (13.2,13.3)

Identify each of the following pairs of Fischer projections as enantiomers or identical compounds: (13.2,13.3)

Identify the chiral carbon if any in each of the following compounds

Identify the Fischer projection A to D  that matches each of the following: (13.1, 13.3)

a. the L enantiomer of mannose

b. a ketopentose

c. an aldopentose

d. a ketohexose

The disaccharide trehalose found in mushrooms is composed of two $\alpha$-D-glucose molecules joined by an $\alpha (1\to 1)$-glycosidic bond. Draw the Haworth structure for trehalose. (13.4,13.6)

$\alpha$-Cellobiose is a disaccharide obtained from the hydrolysis of cellulose. It is quite similar to maltose except it has a $\beta (1\to 4)$-glycosidic bond. Draw the Haworth structure for $\alpha -$cellobiose. (13.4, 13.6)

Why are lactose and maltose reducing sugars, but sucrose is not? (13.6)

Use the Fischer projection for D-gulose in problem $13.69$ to answer each of the following: $(13.3,13.5)$

a. Draw the Fischer projection and name the product formed by the reduction of D-gulose.

b. Draw the Fischer projection and name the product formed by the oxidation of D-gulose.

What are the differences in the Fischer projections of D-fructose and D-galactose? (13.3)