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Antibiotic Resistance:
Case Study



UNIT 1: Biomolecules and Cell Chemistry

What you should know:

All matter is made of tiny atoms. Atoms consist of a nucleus of positively charged protons and neutrally charged neutrons. Negatively charged electrons are arranged outside the nucleus. The arrangement of the electrons determines the type of bonds the atom forms with other atoms. There are three kinds of chemical bonds: ionic, covalent, and hydrogen.

Water is essential to life. The hydrogen bonds between water molecules contribute to important properties of water. Water is an excellent solvent, has strong surface tension and capillary action, has a high degree of cohesion, and has a very stable temperature. Acids increase the hydrogen ion concentration of a solution while bases decrease the hydrogen ion concentration of a solution. The pH scale measures the strength of acids and bases.

Organic compounds are found in all living things. There are four important classes of organic molecules: carbohydrates, lipids, proteins and nucleic acids. Each class of molecules is recognized by its chemical composition and structure as well as its specific role in life. Carbohydrates store energy and give support to the structure of an organism. Lipids are nonpolar molecules that store energy and are an important part of cell membranes. Proteins provide structure for living things and also perform many functions in the organism. Nucleic acids are the blueprints for building the human body. They contain hereditary information.

Chemical reactions absorb or release energy. For a chemical reaction to occur there must be a certain amount of energy called the activation energy. Enzymes are a type of protein in living things that speeds up chemical reactions by decreasing the activation energy needed to start the reaction. Enzymes will only bind to the substrate they match with. Enzyme activity can be affected by temperature and pH.


How you make sense of things:

Initial EPE before lab

Observations you make
in your daily life:

Patterns you notice:
Explanations for the patterns:

Observations of water droplets landing on a penny.

You take Tums when you have an upset stomach.

You eat pasta the night before a track meet for energy.

You eat meat when you want to build muscle.

People who want to lose weight use very little butter on their food, or light butter.

You eat food and it comes out as waste.

Water stays on the penny and forms a dome before it runs off of it.

Meat contains proteins.



Goal EPE after lab

Observations you make during lab:
Patterns you notice in your data:
Explanations for the patterns:

pH lab
pH paper in lemon juice turns red

pH paper in distilled water turns yellow

pH paper in tomato juice turns reddish orange

pH paper in ammonia turns blue

pH paper in vinegar turns red

pH paper in cola turns red

pH paper in milk turns yellowish orange

pH paper in dish washing detergent turns yellowish orange

pH paper in milk of magnesia turns blue

pH paper in chlorine bleach turns blue

Enzymes lab
water + gelatin = no gelatin breakdown

Meat tenderizer + gelatin = gelatin breakdown

Canned pineapple + gelatin = a little gelatin breakdown

Fresh pineapple + gelatin = gelatin breakdown

Biomolecules lab
Apple turns orange/red when Benedict’s solution is added to it.

Butter turns translucent after drying on newsprint paper.

Egg white turns pinkish purple when Biuret reagent is added to it.

Fish turns pinkish purple when Biuret reagent is added to it.

Potato turns blue-black when Lugol’s solution is added to it.

Vegetable oil turns translucent when dried on newsprint.

Water does not react to any of the indicators.

pH lab
orange pH paper turns red in acidic solutions, yellow in neutral solutions, and blue in basic solutions

Enzymes lab
Meat tenderizer and pineapples have enzymes in them.

Biomolecules lab
Fruits contain sugars.

Vegetables contain starches.

Animal based products contain proteins.

Vegetable oil and fats contain lipids.

pH lab
Acidic substances have hydrogen ions in the molecular structure, basic substances have a hydroxide group. Indicators like pH paper react differently to these hydrogen and hydroxide ions.

Enzymes lab
Plants and animals have enzymes in them to help speed up reactions such as the breakdown of gelatin.

Biomolecules lab
Indicators can be used to classify the type of organic molecule that is present. These substances change color due to structural differences in the organic molecules.

All living things are composed of four biomolecules: carbohydrates, lipids, proteins, nucleic acids.

What you should be able to do:

1. Explain the importance of both water and the element carbon to cells.
2. Identify the most common complex molecules that make up living organisms.
3. Describe the composition of the four major categories of organic molecules (carbohydrates, lipids, proteins, and nucleic acids.
4. Explain the general structure and primary functions of the major complex organic molecules that compose living organisms.
5. Explain the role of enzymes and other proteins in biochemical functions (e.g., the protein hemoglobin carries oxygen in some organisms, digestive enzymes, and hormones).

6. Use your knowledge of the four major bio molecules in foods to identify the types of bio molecules in living organisms.