Nursing Elites

1. Balance the chemical equation: C4H10 + O2 → CO2 + H2O. What is the coefficient for oxygen?

• A. 5
• B. 6
• C. 7
• D. 8

Correct answer: B

Rationale: To balance the chemical equation, we need to ensure that the number of each type of atom is the same on both sides of the equation. In this case, there are 10 oxygen atoms on the right side (5 in CO2 and 5 in H2O). To balance this, we need to add a coefficient of 6 in front of O2 on the left side, resulting in 6 O2 molecules. This change will give us a total of 12 oxygen atoms on both sides, making the equation balanced. Choice A (5) is incorrect because it does not account for all the oxygen atoms present in the products. Choices C (7) and D (8) are incorrect as they would result in an imbalance in the number of oxygen atoms on both sides of the equation.

2. Which term describes the quantity of matter in an object and is measured in kilograms or grams?

• A. Weight
• B. Mass
• C. Volume
• D. Density

Correct answer: B

Rationale: Mass is the quantity of matter in an object and is commonly measured in kilograms or grams. It is a fundamental property of matter and remains constant regardless of the object's location. Weight, in contrast, refers to the force of gravity acting on an object and is measured in newtons. Volume represents the amount of space an object occupies and is typically measured in cubic units like cubic meters or cubic centimeters. Density, on the other hand, is the mass of an object per unit volume, and its unit is, for example, kilograms per cubic meter. Therefore, the correct answer is 'Mass' as it specifically describes the quantity of matter in an object, regardless of the gravitational pull on it. 'Weight,' 'Volume,' and 'Density' do not directly represent the quantity of matter in an object but rather different properties related to it.

3. What is the main component that gives bones their rigidity and hardness?

• A. Collagen
• B. Calcium phosphate
• C. Cartilage
• D. Ligaments

Correct answer: B

Rationale: Calcium phosphate is the main component that gives bones their rigidity and hardness. It combines with calcium hydroxide to form hydroxyapatite crystals, which provide strength and structure to bones. Collagen, on the other hand, provides flexibility and tensile strength. Cartilage is a type of connective tissue found in joints, and ligaments are fibrous tissues that connect bones to other bones, but they do not contribute to the rigidity and hardness of bones.

4. What macromolecules are proteins that speed up chemical reactions and act as biological catalysts?

• A. Lipids
• B. Enzymes
• C. Carbohydrates
• D. Nucleic acids

Correct answer: B

Rationale: Enzymes are proteins that act as biological catalysts, speeding up chemical reactions without being consumed in the process. Lipids, carbohydrates, and nucleic acids do not serve as proteins that function as catalysts; they have different biological roles. Lipids are primarily used for energy storage, structural components, and signaling molecules. Carbohydrates are mainly for energy storage and providing structural support. Nucleic acids are involved in genetic information storage and transfer. Therefore, the correct answer is B: Enzymes.

5. Which of these organisms belongs to the kingdom Protista?

• A. Coral
• B. Yeast
• C. Euglena
• D. Mushroom

Correct answer: C

Rationale: A) Coral belongs to the kingdom Animalia, specifically in the phylum Cnidaria. B) Yeast belongs to the kingdom Fungi. C) Euglena is a unicellular organism that belongs to the kingdom Protista. It is a type of protist that has characteristics of both plants and animals. D) Mushroom belongs to the kingdom Fungi. Therefore, among the options provided, only Euglena belongs to the kingdom Protista.

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