U2. the Four Most Important Groups of Organic Compounds in Living Organisms Are

Unit 2 Review Questions

U2. The four most important groups of organic compounds in living organisms are:

1. Carbohydrates, Lipids, Proteins, Nucleic Acids

U2. Which of the four organic compounds would you most likely need more of if your hair is dry and brittle?

1. Protein

U2. Which of the four organic compounds would you most likely need more of if you are really tired all the time?

1. Carbohydrates

U2. Which of the four organic compounds would you most likely need more of if you get cold very easily?

1. Lipids (Fats)

U2. What is the building block (monomer) of a protein?

1. Amino Acid

U2. What is the building block (monomer) of a lipid?

1. Glycerol and Fatty Acids

U2. What is the building block (monomer) of a carbohydrate?

1. Simple Sugar/Monosaccharide/glucose

U2. What is the building block (monomer) of a nucleic acid?

1. Nucleotide

U2. What elements are found in a carbohydrate?

1. Carbon, Hydrogen, Oxygen

U2. What elements are found in a protein?

1. Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur

U2. What elements are found in a lipid?

1. Carbon, Hydrogen, Oxygen

U2. What elements are found in a nucleic acid?

1. Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus

U2. How many different amino acids are there?

1. 20

U2. Two monosaccharides join together to form what?

1. Disaccharide

U2. What is cellulose and where is it found?

1. Sugar found in the cell walls of plants

U2. Is butter a saturated or unsaturated fat? How do you know?

1. Saturated; solid at room temperature

U2. Is vegetable oil a saturated or unsaturated fat? How do you know?

1. Unsaturated; liquid at room temperature

U2. What are two examples of nucleic acids?

1. DNA and RNA

U2. A 5-carbon sugar, phosphate group and a nitrogen base make up what?

1. Nucleotide

U2. What is the most abundant inorganic molecule found in living organisms?

1. Water (H20)

U2. On the pH scale, what is an acid?

1. Less than 7 on the pH scale; contains more hydroxide (OH-) ions than hydrogen (H+) ions

U2. On the pH scale, what is a base?

1. Greater than 7 on the pH scale; contains more hydrogen (H+) ions than hydroxide (OH-) ions

U2. Describe how a buffer helps an organism to maintain homeostasis.

1. A buffer helps an organism to maintain homeostasis by keeping the pH level constant

U2. Why is the pH different in different cells or areas of an organism?

1. Different cells and areas perform better at different levels of pH.

U2 Give examples of carbohydrates.

A Sugar, Potatoes, Starches, Pasta and etc.

U2 Give examples of a lipid.

A Animal Fat, Oils, Nuts, and etc.

U2 What is glycogen and where is it stored in the body?

A A carbohydrate the body uses for longer term storage of energy that it stores in the liver.

U2 How is energy derived from starch?

A Starches are complex sugars that are broken down into simpler sugars for quick energy.

U2 Why are proteins considered some of the most diverse compounds?

A Proteins contain over 20 amino acids, they make up hormones for communication, and enzymes.

U2 Which organic compound would an endurance athlete most likely consume before a race and why?

A Carbohydrates because they are a quick source of energy.

U2 Which types of organic compound would a person trying to lose weight most likely remove from his/her diet?

A Lipids

U2 Describe how DNA differs from RNA.

A DNA is double stranded, has the nucleotide thymine, and is found in side of the nucleus. RNA is single stranded, has the nucleotide Uracil and can be found all over the cell.

U2 Describe the sequence of nucleotides in DNA.

A It codes for genetic information in the cell.

U2 How would the presence of starches be revealed in a test using iodine?

A Iodine reacts with the starches to form a dark blue/black color.

U2 How does an enzyme speed up chemical reactions?

A It lowers the activation energy necessary to begin the reaction.

U2 how does increasing substrate concentration affect enzyme function?

A The enzyme would be unaffected by increasing the substrate.

U2 How do the structures of DNA molecules and nucleotide differ?

A DNA is made up of many nucleotides where a nucleotide is one piece of DNA molecules.

U2 What does the folding of a protein determine?

A Reactivity of the protein and certain substrates.

U2 What is the job of a buffer in the body?

A To prevent pH change and maintain homeostasis.

U2 How can you tell if a substance is organic?

A Carbon and Hydrogen Bonds

U2 Is the following molecule organic or inorganic?

A Organic

U2 Is the following molecule organic or inorganic?

A Inorganic

U2 If small amount of acid is dropped into a pH solution what would happen to the pH of the solution?

A The solution should remain unchanged as it balances out the added Hydrogen Ions from the acid.

U2 Describe a positive Benedict’s test and what it is used to identify.

A A positive test would turn brick red in color after heating and it is used to identify simple sugars.

U2 Describe a positive Iodine test and what it is used to identify.

A A positive iodine test would turn blue/black in color in the presence of starches.

U2 Identify the following Macromolecule.

A.  Polysaccharide

U2 Describe a positive brown paper bag test and what it is used to identify.

A A positive paper bag test will turn translucent in color in the presence of lipids.

U2 Identify the following Macromolecule.

A Lipids

U2 List and describe the different functions of proteins. Hint: There are 6.

A Pigments - absorb/reflect light, Antibodies - binds with inactive foreign particles in the body, Keratin - structures the form from proteins (Hair/Nails), Transport Proteins - Moves nutrients throughout the body (Hemoglobin), Communication - Hormones that are released to regulate body processes, and Maintain homeostasis - speeds up chemical reactions (Enzymes)

U2 Identify the following molecule.

A Amino Acid

U2 Describe the different parts of a nucleotide.

A Phosphate group, 5 Carbon Sugar, and a Nitrogenous base.

U2 What is the function of DNA?

A Control Genetic Information

U2 What is the function of RNA?

A Make proteins to make traits.

U2 What is a catalyst?

A Something that speeds up or slows down a reaction.

U2 Describe the enzyme substrate complex.

A It is the process in which the enzyme and substrate fit together to speed up a chemical reaction.

U2 What is the energy that is required to start a chemical reaction called?

A Activation Energy

U2 Describe the shape of an enzyme.

A Specific to a substrate and 3D

U2 Describe what happens to an enzyme after it has been used in a chemical reaction.

A It is unchanged.

U2 What are two ways in which enzyme may become denatured or “changed”?

A Through extreme temperatures hot/cold, and changes in pH High/Low

U2 Define denaturing of an enzyme.

A The enzyme changes shape and becomes less reactive or nonreactive.

U2 List a few items in which enzymes assist with in the body.

A Break down proteins, carbohydrates, nucleic acids, and lipids.

U2 How do you idenify the following items by their name:

Carbohydrates - A: -ose

Lipids A: -ide

Proteins A: -in

Enzymes A: -ase