Nokea
What function do hydrophobic proteins often provide in the body?
- A. Digestive enzymes
- B. Provide structure
- C. Carry oxygen molecules
- D. Store energy
Correct Answer: B
Rationale: Hydrophobic proteins are known for their ability to repel water and are often involved in providing structural support in cells and tissues. They help maintain the structural integrity and shape of cell membranes, organelles, and other cellular components. Choice A, digestive enzymes, typically consist of hydrophilic proteins that interact with water and substrates to facilitate digestion. Choice C, carrying oxygen molecules, is a function commonly associated with specific proteins like hemoglobin. Choice D, storing energy, is usually performed by proteins like enzymes involved in energy storage and release, such as glycogen phosphorylase.
You may also like to solve these questions
Which of the following best describes the process of osmosis?
- A. Movement of molecules against their concentration gradient
- B. Movement of water across a selectively permeable membrane
- C. Movement of water and solutes together
- D. Movement of large molecules through a membrane
Correct Answer: B
Rationale: The correct answer is B. Osmosis is the process where water moves across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration. Choice A is incorrect because osmosis does not involve movement against the concentration gradient. Choice C is incorrect because osmosis primarily involves the movement of water, not water and solutes together. Choice D is incorrect as osmosis specifically refers to the movement of water molecules, not large molecules, through a membrane.
Which of the following bones is part of the axial skeleton?
- A. Femur
- B. Humerus
- C. Skull
- D. Pelvis
Correct Answer: C
Rationale: The correct answer is C: Skull. The axial skeleton consists of bones along the body's central axis, including the skull, vertebral column, ribs, and sternum. Choices A, B, and D are incorrect because the femur, humerus, and pelvis are part of the appendicular skeleton, which comprises the bones of the limbs and girdles.
Which type of muscle is responsible for moving the skeleton?
- A. Cardiac muscle
- B. Skeletal muscle
- C. Smooth muscle
- D. Voluntary muscle
Correct Answer: B
Rationale: Skeletal muscle is the correct answer as it is responsible for moving the skeleton. Skeletal muscles are under voluntary control, meaning they can be consciously controlled by the individual. Cardiac muscle (Choice A) is found in the heart and is responsible for pumping blood, not moving the skeleton. Smooth muscle (Choice C) is found in internal organs and is responsible for involuntary movements like digestion. Voluntary muscle (Choice D) is not a specific type of muscle; it refers to muscles that can be consciously controlled, which includes skeletal muscles.
What is the maximum volume of air that can be expelled from the lungs after maximum inhalation?
- A. Tidal volume
- B. Total lung capacity
- C. Ventilation rate
- D. Vital capacity
Correct Answer: D
Rationale: The correct answer is D, Vital capacity. Vital capacity represents the maximum volume of air that can be expelled from the lungs after a maximum inhalation. Tidal volume (Choice A) is the volume of air inspired or expired during normal breathing at rest and is not the maximum capacity. Total lung capacity (Choice B) refers to the maximum volume of air the lungs can accommodate including the residual volume, not just the expelled air. Ventilation rate (Choice C) is the rate at which air is moved in and out of the lungs, not the maximum volume of air that can be expelled.
Where is keratin found?
- A. It is a protein-digesting enzyme released by the stomach.
- B. It is released in the neuromuscular junction.
- C. It is a protein found in the hypodermis.
- D. It is a protein found in hair.
Correct Answer: D
Rationale: Keratin is a structural protein found in hair, skin, and nails, providing strength and protection. It forms the main structural component of hair, making choice D the correct answer. Choices A, B, and C are incorrect because keratin is not an enzyme released by the stomach, not released in the neuromuscular junction, and not found in the hypodermis. Remember that keratin is primarily associated with structural support in epithelial cells.