Biology MCAS Prep 11/18 and 11/25

Topic: Digestive System

Question of the Day:

What happens to a meal of a cheeseburger and French fries in the digestive and endocrine system?

Key terms: Carbohydrate, Lipid, Nucleic Acid, Protein, Mouth, Esophagus, Stomach, Small Intestine, Large Intestine, Absorption (context of cell transport terms), Mechanical, Chemical, Enzyme

Open Response: Just do Part A for today.

The digestion of dairy milk provides the body with important nutrients.

a. Describe how the digestive system converts the carbohydrates, proteins, and fats in dairy milk or soymilk into nutrients that can be used by cells. Include the body parts and organs involved.

b. Describe how the nutrients in the digestive system are made available to cells throughout the body after digestion has occurred. Include the body parts and organs involved.

Multiple Choice:

1. In which part of the human digestive system do both physical breakdown and chemical breakdown of food first begin?

A. / esophagus
B. / Mouth
C. / large intestine
D. / small intestine

2. Heartburn is pain that occurs when acidic gastric juice is forced out of the upper end of the stomach. In which of the following organs does a person experience heartburn?

A. / pancreas
B. / esophagus
C. / small intestine
D. / large intestine

3. When lactose is digested by the human body, each lactose molecule is broken down into smaller molecules. To which of the following categories of molecules do these smaller molecules belong?

A. / amino acids
B. / monosaccharides
C. / nucleic acids
D. / polypeptides

4. What is the primary function of the large intestine?

A. / to digest proteins
B. / to absorb nutrients
C. / to break down complex carbohydrates
D. / to remove water from undigested waste

5. The table below provides information about the composition and function of four important molecules in living organisms.

Molecule / Composition / Function
1 / amino acids / reaction
catalyst
2 / fatty acids / membrane
component
3 / monosaccharides / energy
source
4 / nucleotides / genetic
information

Which of the molecules in this table is a carbohydrate?

A / 1
B / 2
C / 3
D / 4

6. Which group of organic compounds contains fatty acids?

A. / carbohydrates
B. / lipids
C. / nucleic acids
D / proteins

7. Cellulose is a complex carbohydrate that makes up the cell walls of plants. Which of the following elements are maincomponents of cellulose?

A. / calcium and chlorine
B. / carbon and hydrogen
C. / potassium and chlorine
D. / sodium and hydrogen

8. Resistance to antibiotics results from variations in the genetic code of Streptococcus pneumoniae. Which type of molecule encodes genetic information in Streptococcus pneumoniae?

A. / carbohydrate
B. / fatty acid
C. / nucleic acid
D. / protein

9. Vitamin D is an organic molecule that regulates the absorption of calcium by the body. Which of the following elements is most common in a molecule of vitamin D?

A. / aluminum
B. / carbon
C. / magnesium
D. / sodium

10. Which of the following roles does an enzyme play when the body processes sucrose (table sugar) into glucose and fructose?

A. / An enzyme decreases the body’s need for sucrose.
B. / An enzyme increases the amount of sucrose available.
C. / An enzyme increases the rate at which the sucrose breaks down.
D. / An enzyme decreases the amount of fructose and glucose product available.

11. The role of an enzyme in a chemical reaction is to change which of the following?

A. / the type of reaction
B. / the activation energy of the reaction
C. / the pH at which the reaction occurs
D / the temperature at which the reaction occurs

12. The graph below shows how the activity of an enzyme changes over a range of pH values.

Which of the following conclusions is supported by the data?

A. / The optimum pH of the enzyme is 6.6.
B. / The optimum pH of the enzyme is 5.8.
C. / The enzyme’s activity is greater around pH 8.0 than around pH 5.0.
D. / The enzyme’s activity continually increases as pH increases from 5.0 to 9.0.

13. An amoeba in a pond engulfs and consumes a paramecium. The amoeba uses which of the following to quickly break down the organic molecules in the paramecium?

A. / enzymes
B. / glucose
C. / polysaccharides
D. / water

13. Fatty acids are one of the products that result from the action of lipase in the digestive system. What is one way that fatty acids are used in the body?

A. / for storing energy
B. / for encoding genetic information
C. / as the building blocks of antibodies
D. / as the building blocks of hemoglobi

14. What is the primary role of the stomach in the human digestive system?

A. / producing specialized salts that absorb fats
B. / absorbing water and minerals from undigested food
C. / using muscle movements and enzymes to break down food
D / transferring nutrients from digested food to the bloodstream

15. Crohn’s disease causes inflammation of the digestive tract, particularly the small intestine. Inflammation of the small intestine would directly interfere with which of the following digestive functions?

A. / liquefying food
B. / reabsorbing water
C. / absorbing nutrients
D / moving food to the stomach