The highest stores of energy (kcal/g) in the body are found in:
Fat
Carbohydrate
Protein, carbohydrate and fat equally
Protein
The Correct Answer is A
The body stores energy in various forms to ensure a constant supply of fuel during fasting or high metabolic demand. These macronutrients differ in their chemical structure and the amount of energy released upon complete oxidative catabolism. Energy density is measured in kilocalories per gram (kcal/g). Efficient storage is necessary to minimize the physical mass of the body's energy reserves.
Rationale:
A. Fat (lipids) possesses the highest energy density at approximately 9 kcal/g. This is because fatty acid chains are highly reduced hydrocarbons, allowing them to release more energy when oxidized to CO2 and water. Furthermore, fat is stored in a relatively anhydrous (water-free) state, maximizing the caloric value per unit of mass.
B. Carbohydrates provide approximately 4 kcal/g of energy. They are stored as glycogen in the liver and skeletal muscle. Glycogen is a hydrophilic molecule and is stored with a significant amount of water, which greatly reduces the overall energy-to-weight ratio compared to the dense storage found in adipose tissue.
C. This choice is scientifically incorrect as the macronutrients do not provide equal energy. The caloric yield is determined by the oxidation state of the carbon atoms in the molecule. Fats are significantly more energy-dense than both proteins and carbohydrates, yielding more than double the energy per gram than the other two.
D. Protein also provides approximately 4 kcal/g of energy. While the body can use protein for energy through gluconeogenesis or direct oxidation of carbon skeletons, it is primarily used for structural and functional purposes. Using protein as a primary energy store is inefficient and leads to the loss of muscle mass.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is A
Explanation
Step 1 is to calculate the Least Weighable Quantity (LWQ)
LWQ = (Sensitivity Requirement ÷ Acceptable Error) × 100
(5 ÷ 5) × 100
5 ÷ 5 = 1
1 × 100 = 100
Result at this step = 100 mg
Step 2 is to determine the drug multiplication factor
Since the required dose is 5 mg and we must weigh at least 100 mg:
Factor = 100 ÷ 5
100 ÷ 5 = 20
Result at this step = 20
Step 3 is to calculate the total mixture weight (drug + diluent)
Total Mixture = Aliquot weight × Factor
100 × 20 = 2000
Result at this step = 2000 mg
Step 4 is to calculate the amount of diluent needed
Diluent = Total Mixture - Drug weight
2000 - 100 = 1900
Result at this step = 1900 mg
Correct Answer is D
Explanation
Superficial mycoses represent fungal infections limited to the stratum corneum and its associated appendages. These pathogens produce keratinase enzymes that degrade structural proteins for nutrient acquisition. Unlike cutaneous mycoses, they typically elicit minimal host immune response because they do not penetrate the deeper viable epidermis. Common examples include Pityriasis versicolor and various Tinea species that affect the outermost integumentary layers.
Rationale:
A. The skin, specifically the keratinized epidermis, is a primary site for superficial fungal colonization. Fungi such as Malassezia furfur thrive in the lipid-rich environment of the skin surface. These infections often result in hypopigmentation or hyperpigmentation but lack deep tissue inflammation. Consequently, skin involvement is a defining feature of the superficial clinical presentation.
B. Hair shafts are frequently colonized by superficial fungi, leading to conditions like black piedra or white piedra. The fungi attach to the hair cuticle and form nodules or weaken the structural integrity of the hair fiber. This colonization is restricted to the non-living portion of the hair. Therefore, hair is an essential anatomical component affected by these mycological organisms.
C. Nails consist of densely packed keratinized cells that provide an ideal substrate for fungal dermatophytes. Superficial fungal involvement of the nail plate is common, leading to discoloration and brittleness without affecting the underlying viable nail bed. While often categorized with cutaneous mycoses, the initial colonization involves the outer keratinized shell. Nails are thus a major target of these pathogens.
D. All of the above is the correct answer because superficial mycoses are characterized by their affinity for all keratin-containing tissues. This includes the epidermal layer of the skin, the shaft of the hair, and the hard plates of the nails. Because these fungi specialize in utilizing keratin as a carbon source, they naturally distribute across these three anatomical structures.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.