1. Salivary amylase is a digestive enzyme which begins the digestion of ____

   1. Proteins

   2. Starch

   3. Lipids

   4. Glucose

   5. Nucleic acids

2. The ____ exits directly from the gallbladder

   1. Right hepatic duct

   2. Left hepatic duct

   3. Cystic duct

   4. Common bile duct

   5. Common hepatic duct

3. All of the following are areas of the stomach except ____

   1. Cardia

   2. Duodenum

   3. Fundus

   4. Body

   5. pylorus

4. Mumps is an inflammation and enlargement of the ___

   1. Appendix

   2. Gallbladder

   3. Pancreas

   4. Parotid glands

   5. tonsils

1. What is activation energy?

A. The energy used by the active site to split a substrate.

B. The energy released when a substrate binds to an active site.

C. The energy required to start a metabolic reaction.

D. The energy required to raise the temperature of 1 gram of water by 1 degree Celsius.

2. Which statement defines your body's metabolic rate?

A. The speed at which chemical reactions occur when you are resting but awake

B. The number of Calories needed to keep your weight stable

C. All of the chemical reactions in your body

D. A measure of your body’s energy use

3. Which statement about enzymes is true?

A. One enzyme can catalyze many different types of reactions for a variety of substrates.

B. The shape of an enzyme determines its specificity.

C. Enzymes eliminate the activation energy barrier.

D. An enzyme molecule is permanently changed by the substrate molecule.

4. Which reaction occurs during glycolysis?

A. Glucose is converted into carbon dioxide.

B. Glucose is converted into water.

C. Glucose is converted into ATP.

D. Glucose is converted into pyruvic acid.

Part A -tRNA interactions with mRNA and the ribosome

Ribosomes provide the scaffolding on which tRNAs interact with mRNA during translation of an mRNA sequence to a chain of amino acids. A ribosome has three binding sites, each of which has a distinct function in the tRNA-mRNA interactions.

Drag the appropriate tRNAs to the binding sites on the ribosome to show the configuration immediately before new peptide bond forms. Note that one of the binding sites should be left empty.

How would the mutation described above, changing a lysine to an arginine alter the histone code if this lysine was located on the histone tail? What possible effects could this have? Histone proteins are the most conserved proteins of all eukaryotic proteins. That is to say that there is very little variation in the sequence of amino acids from one species to another. Why do you think this is? Please note that this is a 10 point question, please provide ample evidence.  

2. Why is it relevant for biochemists to consider the acid/base properties of amino acids?

3. What are the conventions for displaying a peptide sequence?

4. What chemical characteristic(s) of the peptide bond make it rigid and planar?

5. What are 1-2 concepts you continue to struggle with from the reading?

6. Write one broader question that reading raises for you. This question could relate to applications of concepts to medicine, research, etc

Which of the following best describes the tRNA binding sites of the ribosome?

Group of answer choices

A. The P site contains the tRNA molecule covalently bound to the growing chain of amino acids.

B. All tRNAs leave the ribosome through the A site.

C. Only one of the three sites can be occupied by a tRNA molecule at any given time.

D. Each tRNA that associates with the ribosome must first bind in the P site and then moved to the A site.

1) Explain how the body metabolizes carbohydrates and protein in the fed state.

2) Explain how the body metabolizes carbohydrates and fat in the fed state.

3) Explain how the body metabolizes carbohydrates and amino acids in the short term fasting states (prior to using up all your glycogen).

4) Explain how the body metabolizes fats in the fasting state once you have used up all your glycogen stores.

What is a codon and how do you identify them in a strand of mRNA? There are 64 potential codons for only 20 amino acids. Why does this occur? Why is it also important to know the start codon before determining what a codon would be in a given strand of mRNA? After answering this first part, explain the difference between the DNA template and coding strands and explain how each strand relates to the mRNA strand that is produced?

6. Distinguish between single step selection and cumulative selection. e.g how long would it take to find the correct sequence of polypeptide that was 100 amino acids long? What is about cumulative selection that makes it so much more efficient at finding the correct sequence? How does the program demonstrating cumulative selection differ from the real process of natural selection? You should be able to come up with at least three differences.

Which of the following is TRUE?

The hepatic portal vein transports water-soluble vitamins, amino acids and monosaccharides from the small intestine to the liver.

The hepatic portal vein transports lipids from the small intestines to the liver

The lymphatic system transports water-soluble vitamins, amino acids and monosaccharides from the small intestine to the liver

Question 2

Which of the following is TRUE about the stomach?

It contains 3 layers of smooth muscle that contract to mechanically break up food particles and propel food forward by peristalsis

It contains Endocrine glands that secrete Gastrin into the stomach

Small polypeptides are absorbed by endocytosis from the stomach

Question 3

The intestinal phase of digestion _________________________.

Slows gastric emptying to ensure that nutrients entering the small intestine are digested and absorbed.

Stimulates the gastroenteric reflex

Maintains homeostasis of blood pH

Prevents gastroesophageal refulx

Question 4

The interstitial cells of Cajal are _________________________.

Pacesetter cells of the enteric nervous system

Afferent sensory neurons of the enteric nervous system

The extrinsic neurons that innervate the enteric nervous system

Question 5

Which monosaccharide uses secondary active co-transport with sodium (a SGLT) for absorption across the apical membrane of the Small Intestine?

Glucose

Lactose

Sucrose

Maltose