Question

1. keratin and chitin are both biological compounds produced by different species. they can both form hard compounds designed to protect other structures. both molecules are brought together in specific patterns and structures, but chitin is made from complex chains of sugars, while keratin is made of amino acids. how should chitin and keratin be labeled? a chitin: lipid; keratin: carbohydrate b chitin: protein; keratin: nucleic acid c chitin: nucleic acid; keratin: lipid d chitin: carbohydrate; keratin: protein 31. honeycombs are structures produced inside of beehives for the production of honey and growth of bee larvae. the honeycomb is made from a wax material called beeswax, which is edible by certain organisms and changes physical properties as the temperature changes. the beeswax is a hydrocarbon molecule that at room temperature is a solid, does not dissolve in water, and is water - repellent. it is this combination of properties that allows the beeswax to be so useful in making honeycombs. how should beeswax be classified? a it should be classified as a carbohydrate because it is eaten by certain organisms. b it should be classified as a protein because it is a solid at room temperature. c it should be classified as a lipid because it does not dissolve in water and is water - repellent. d it should be classified as a nucleic acid because it is a hydrocarbon molecule and changes properties as the temperature changes. 39. the model shows the basic structure of a nucleic acid. which part of the model represents the nitrogenous base? a part 1 b part 2 c part 3 d part 4

Explanation:

Question 20:

Chitin is a polysaccharide (a type of carbohydrate) made from complex chains of sugars. Keratin is a protein made of amino - acids.

Question 31:

Lipids are non - polar and water - repellent, and do not dissolve in water. Beeswax has these properties, so it is a lipid.

Question 39:

In a nucleic acid structure, the nitrogenous base is the part that contains nitrogen. In the given model, Part 1 is the nitrogenous base.

Answer:

Question 20: D. chitin: carbohydrate; keratin: protein

Question 31: C. It should be classified as a lipid because it does not dissolve in water and is water - repellent.

Question 39: A. Part 1