Nokea
Which of these body parts does not contain melanin?
- A. Hair
- B. Nails
- C. Skin
- D. Iris
Correct Answer: D
Rationale: The iris is the colored part of the eye that determines the eye's color. Melanin is not present in the iris, unlike hair, nails, and skin. Melanin gives color to hair, nails, and skin, but not to the iris. Therefore, the correct answer is the iris (Choice D). Choices A, B, and C contain melanin and are incorrect.
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Which of the following terms describes the enlargement of an organ or tissue?
- A. Dystrophy
- B. Atrophy
- C. Hypertrophy
- D. Eutrophy
Correct Answer: C
Rationale: Hypertrophy refers to the enlargement of an organ or tissue, typically due to an increase in the size of individual cells. This can occur in response to increased workload, hormonal stimulation, or other factors. On the other hand, dystrophy refers to the degeneration and deterioration of tissue, atrophy describes the decrease in the size of an organ or tissue, and eutrophy denotes a state of normal nutrition or growth. Therefore, the correct answer is 'Hypertrophy' as it specifically relates to the increase in size or volume of an organ or tissue.
Which of the following statements is FALSE?
- A. An organelle is a specialized structure in a cell, such as a ribosome.
- B. An organ is made up of different types of tissues that work together to perform specific functions.
- C. Organ systems are two or more organs performing similar functions.
- D. A tissue contains a variety of cells that work together to perform a specific function.
Correct Answer: B
Rationale: The statement provided in Option B is FALSE. Organs are actually made up of different types of tissues that work together to perform specific functions, rather than being composed of similar tissues. Organs consist of various tissues, each with their own specialized functions that collectively contribute to the overall function of the organ. Options A, C, and D are true statements. Option A correctly defines an organelle as a specialized structure in a cell, like a ribosome. Option C accurately describes organ systems as multiple organs working together to perform related functions. Option D correctly explains that a tissue is composed of different cells working together to carry out a specific function.
Which organ system is most responsible for maintaining control of body temperature?
- A. The skeletal system.
- B. The circulatory system.
- C. The immune system.
- D. The muscular system.
Correct Answer: B
Rationale: The circulatory system is the correct answer as it plays a crucial role in maintaining control of body temperature through a process called thermoregulation. Blood vessels near the skin surface dilate to dissipate heat when the body is too warm and constrict to reduce heat loss when it's too cold. Additionally, the circulatory system helps distribute heat produced from metabolic processes throughout the body to keep a stable internal temperature. The skeletal system provides structural support, the immune system defends against pathogens, and the muscular system is responsible for movement, but they are not primarily involved in regulating body temperature.
Which of the following terms means close to the trunk of the body?
- A. Superficial
- B. Sagittal
- C. Proximal
- D. Distal
Correct Answer: C
Rationale: The term 'proximal' means situated close to the point of attachment or the center of the body, such as close to the trunk. In anatomical terms, proximal is used to describe locations that are closer to the body's center or point of reference. 'Superficial' refers to something situated near the surface, 'sagittal' refers to a plane that divides the body into left and right portions, and 'distal' refers to a position away from the center or point of reference. Therefore, 'proximal' is the correct term to indicate a position close to the trunk of the body.
What is the name of the outermost layer of the skin?
- A. Dermis
- B. Epidermis
- C. Subcutaneous tissue
- D. Hypodermis
Correct Answer: B
Rationale: The correct answer is B: Epidermis. The epidermis is the outermost layer of the skin, providing a protective barrier against external factors. The dermis is situated beneath the epidermis and contains structures like blood vessels and hair follicles. Subcutaneous tissue, also known as the hypodermis, lies below the dermis and consists mainly of fat tissue, serving functions such as insulation and energy storage. Therefore, choices A, C, and D are incorrect as they do not represent the outermost layer of the skin.