Nokea
Which part of the brainstem is responsible for controlling vital functions such as heart rate, blood pressure, and breathing?
- A. Medulla oblongata
- B. Pons
- C. Midbrain
- D. Cerebellum
Correct Answer: A
Rationale: The medulla oblongata is the correct answer. It is responsible for controlling vital functions such as heart rate, blood pressure, and breathing. This part of the brainstem contains centers that regulate these essential autonomic functions to maintain homeostasis in the body. The pons and midbrain are also parts of the brainstem, but they are not primarily responsible for controlling these vital functions. The cerebellum, on the other hand, is involved in coordination and balance, not in regulating vital functions like heart rate, blood pressure, and breathing.
You may also like to solve these questions
When unpolarized light passes through a polarizing filter, the intensity of the transmitted light is:
- A. Completely absorbed
- B. Reduced by half
- C. Unaffected
- D. Doubled
Correct Answer: B
Rationale: When unpolarized light passes through a polarizing filter, the filter only allows light waves oscillating in a specific direction to pass through while blocking light waves oscillating in other directions. Since unpolarized light consists of light waves oscillating in all possible directions, when it passes through a polarizing filter, only half of the light waves (those oscillating in the direction allowed by the filter) are transmitted. As a result, the intensity of the transmitted light is reduced by half. Choice A is incorrect because the light is not completely absorbed; choice C is incorrect because the polarizing filter affects the transmitted light; and choice D is incorrect because the intensity does not double, but rather decreases by half due to the selective transmission of light waves in a specific direction by the polarizing filter.
What element is responsible for the green color of leaves?
- A. Magnesium
- B. Iron
- C. Copper
- D. Zinc
Correct Answer: A
Rationale: Magnesium is the correct answer. It is essential for the formation of chlorophyll, the green pigment in plants that is crucial for photosynthesis. Chlorophyll absorbs sunlight and uses its energy to convert carbon dioxide and water into glucose and oxygen. Iron, copper, and zinc do not play a direct role in the green color of leaves. Iron is more related to processes like electron transport, copper is involved in enzyme functions, and zinc contributes to the synthesis of plant growth regulators.
Muscles that work together to produce a specific movement are called
- A. Antagonistic muscles
- B. Agonistic muscles
- C. Synergistic muscles
- D. Flexors and extensors
Correct Answer: C
Rationale: Synergistic muscles are groups of muscles that work together in a coordinated manner to produce a specific movement. They synchronize their actions to achieve a common goal efficiently. In contrast, antagonistic muscles work in opposing directions, and agonistic muscles, also known as prime movers, are responsible for initiating a movement. Flexors and extensors represent muscles that perform contrasting actions around a joint, such as bending and straightening. Therefore, the correct answer is C - 'Synergistic muscles,' as they collaborate to facilitate a specific movement, unlike the other choices which describe different muscle functions within the body.
Which of the following is the outermost layer of the skin, providing protection against pathogens and the environment?
- A. Dermis
- B. Epidermis
- C. Hypodermis
- D. Stratum corneum (part of the epidermis)
Correct Answer: B
Rationale: The epidermis is the correct answer as it is the outermost layer of the skin, providing protection against pathogens and the environment. It consists of multiple layers, including the stratum corneum, which is the outermost layer of the epidermis. The dermis is located beneath the epidermis, offering structural support and housing blood vessels, nerves, and glands. The hypodermis is the deepest layer of the skin, made up of fat and connective tissue that secures the skin to underlying structures. Choice A, Dermis, is incorrect as it is located beneath the epidermis. Choice C, Hypodermis, is incorrect as it is the deepest layer of the skin, not the outermost. Choice D, Stratum corneum (part of the epidermis), is not the correct answer as it is a specific layer within the epidermis and not the overall outermost layer of the skin.
What is kwashiorkor, a protein deficiency disease, characterized by?
- A. Muscle wasting
- B. Night blindness
- C. Scurvy
- D. Rickets
Correct Answer: A
Rationale: Kwashiorkor is a severe acute malnutrition condition resulting from insufficient dietary protein intake. It is characterized by symptoms such as edema, skin lesions, an enlarged liver with fatty infiltrates, and notably, muscle wasting. Muscle wasting occurs as the body breaks down muscle tissue to obtain essential amino acids for vital functions. Night blindness (option B) is associated with vitamin A deficiency, scurvy (option C) results from a lack of vitamin C, and rickets (option D) is caused by a deficiency in vitamin D, calcium, or phosphate.