Plants synthesize the sugar dextrose according to the following reaction by absorbing radiant energy from the sun (photosynthesis).

$$6 \mathrm{CO}_2(g)+6 \mathrm{H}_2 \mathrm{O}(g) \rightleftharpoons \mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6(s)+6 \mathrm{O}_2(g)$$

Will an increase in temperature tend to favor or discourage the production of $\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6(s)$?

Balancing Chemical Equations Sucrose, $C_{12}H_{22}O_{11}$, is a sugar that is used to sweeten many foods. Inside the body, it is broken down to produce $H_2O$ and $CO_2$. $\mathrm { C } _ { 12 } \mathrm { H } _ { 22 } \mathrm { O } _ { 11 } + 12 \mathrm { O } _ { 2 } \rightarrow 12 \mathrm { CO } _ { 2 } + 11 \mathrm { H } _ { 2 } \mathrm { O }$ List all of the mole ratios that can be determined from this equation.

Hospital patients are often given glucose (blood sugar) through a tube connected to a bottle suspended over their beds. Suppose that this “drip” supplies glucose at the rate of 25 mg per minute, and each minute 10% of the accumulated glucose is consumed by the body. Then the amount y(t) of glucose (in excess of the normal level) in the body after t minutes satisfies $y^{\prime}=25-0.1 y$ (Do you see why?) $y(0) = 0$ (zero excess glucose at t = 0) Solve this differential equation and initial condition.

Sucrose, $\mathrm{C}_{12} \mathrm{H}_{22} \mathrm{O}_{11}$, is a sugar used to sweeten many foods. Inside the body, it is broken down to produce $\mathrm{H}_{2} \mathrm{O}$ and $\mathrm{CO}_{2}.$

$$\mathrm{C}_{12} \mathrm{H}_{22} \mathrm{O}_{11}+12 \mathrm{O}_{2} \longrightarrow 12 \mathrm{CO}_{2}+11 \mathrm{H}_{2} \mathrm{O}$$

List all of the mole ratios that can be determined from this equation.

Recall the sugar content of the syrup in canned peaches. Suppose that the variance is thought to be $\sigma^{2}=18$(milligrams)$^{2}$. A random sample of n = 10 cans yields a sample standard deviation of s = 4.8 milligrams. (a) Test the hypothesis $H_{0}: \sigma^{2}=18$ versus $H_{1}: \sigma^{2} \neq 18$ using $\alpha=0.05$. (b) What is the P-value for this test? (c) Discuss how part (a) could be answered by constructing a 95% two-sided confidence interval for $\sigma$.

The blood sugar (glucose) level of a diabetic patient is approximately $0.140 \mathrm{~g}$ of glucose $/ 100 \mathrm{~mL}$ of blood. Every time the patient ingests $40 \mathrm{~g}$ of glucose, her blood glucose level rises to approximately $0.240 \mathrm{~g} / 100 \mathrm{~mL}$ of blood. Calculate the number of moles of glucose per milliliter of blood and the total number of moles and grams of glucose in the blood before and after consumption of glucose. (Assume that the total volume of blood in her body is $5.0 \mathrm{~L}$.)

Trehalose is a disaccharide that can be obtained from yeasts, fungi, sea urchins, algae, and insects. Deduce the structure of trehalose from the following information: 1. Acid hydrolysis of trehalose yields only D-glucose. 2. Trehalose is hydrolyzed by $\alpha$ -glucosidase but not by $\beta$ -glucosidase enzymes. 3. Trehalose is a nonreducing sugar; it does not mutarotate, form a phenylosazone, or react with bromine water. 4. Methylation of trehalose followed by hydrolysis yields two molar equivalents of 2,3,4,6 -tetra-O-methyl-D-glucose.

Fructose is a sugar commonly found in fruit. A sample of fructose, $\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6$, weighing $4.50 \mathrm{~g}$ is burned in a bomb calorimeter. The heat capacity of the calorimeter is $2.115 \times 10^4 \mathrm{~J} /{ }^{\circ} \mathrm{C}$. The temperature in the calorimeter rises from $23.49^{\circ} \mathrm{C}$ to $27.71^{\circ} \mathrm{C}$. (a) What is $q$ for the calorimeter? (b) What is $q$ when $4.50 \mathrm{~g}$ of fructose is burned? (c) What is $q$ for the combustion of one mole of fructose?

Roger is comparing a model of a sugar molecule to a model of an amino acid. Which of the following evidence statements would be supported by the two models? A. Sugars and amino acids are made of exactly the same elements. B. Sugars and amino acids have the same structure. C. Sugars and amino acids are made of the same elements but amino acids also contain nitrogen. D. Sugars and amino acids are made of the same elements but sugars also contain phosphorus. E. Sugars and amino acids are both polymers.

Label each as a chemical change (CC) or physical change (PC). a. Burning match b. Melting ice c. Boiling water d. Tearing a piece of paper e. Digestion of food f. Rusting of iron g. Dissolving salt in water h. Evaporating water from sugar water i. Adding food coloring to water j. Reacting sodium metal with water k. Breaking glass I. Melting glass m. Weathering copper (forms a green patina) n. Forming a precipitate o. Crystallizing rock candy

Glucose, also known as "blood sugar" when measured in blood, has the formula $\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6$. (a) Write the equation for the combustion of glucose with $\mathrm{O}_2$ to give $\mathrm{CO}_2$ and $\mathrm{H}_2 \mathrm{O}$. (b) If 3.8 kcal is released by combustion of each gram of glucose, how many kilojoules are released by the combustion of 1.50 mol of glucose? (c) What is the minimum amount of energy a plant must absorb to produce 15.0 g of glucose?

The study mentioned in one example also looked at the severity of fever (rated as mild, moderate or severe) for all subjects who developed one after receiving a flu shot . The following table shows counts for subjects randomized to the group that received the active ingredient of the flu shot and the placebo group that received a sugar injection.

The P-value for the chi-squared test equals 0.287. Write the conclusion of the test in context.

(a) For each $\mathrm{OH}$ group in open-chain glucose, indicate if it is primary, secondary, or tertiary. (b) Does tyrosine contain an ortho-, meta-, or para-substituted aromatic ring?
(c) How many amino acids are in a pentapeptide? How many molecules of water were lost when it was formed?
(d) Based on what you know about the hydrolysis of disaccharides, if a person has high blood sugar levels, do you think it would be better for this person to cut down on lactose or maltose? Why?

Lawns are sometimes fertilized with nitrate that can be washed into neighboring woodlots by rain. If the trees in that woodlot are associated with EMF, what effect might the excess nitrate have on the fungi and/or trees?

a. Fungal growth may be stimulated, causing the trees to transport more nitrogen to the fungi.
b. The fungi may secrete more peptidases to break down the nitrate.
c. The trees may take up the nitrate directly into their roots and rely less on the fungi.
d. The excess nitrate may stimulate the fungi to transport more sugar to the trees.