Expiratory muscles contract at the time of

Correct Answer: C

Rationale: The correct answer is C: Forceful expiration. Expiratory muscles contract during forceful expiration to increase intra-abdominal pressure and expel air from the lungs effectively. During normal expiration, these muscles are relaxed. Choice A is incorrect because deep inspiration involves the contraction of inspiratory muscles, not expiratory muscles. Choice B is incorrect because normal inspiration does not involve expiratory muscles contraction. Choice D is incorrect because normal expiration does not require the forceful contraction of expiratory muscles.

Correct Answer: D

Rationale: Opercular gills are found in both Lepidosteus and Polypterus, making choice D the correct answer. Lepidosteus, commonly known as the gar, and Polypterus, known as the bichir, are primitive fish species with opercular gills, which are a key feature in their respiratory system. Anabas, on the other hand, also known as the climbing perch, does not have opercular gills. Therefore, choices A, B, and C are incorrect as they do not possess opercular gills like Lepidosteus and Polypterus.

Correct Answer: D

Rationale: The correct answer is D because vital capacity measures the maximal volume of air exhaled from the point of maximal inspiration. This measurement includes the tidal volume, inspiratory reserve volume, and expiratory reserve volume. A is incorrect because it describes tidal volume. B is incorrect because it describes total lung capacity. C is incorrect because it describes inspiratory capacity. Therefore, D is the most appropriate choice for measuring vital capacity accurately in a patient with neuromuscular disorders like multiple sclerosis.

Correct Answer: D

Rationale: Correct Answer: D Rationale: 1. An injury to tissue can lead to inflammation, activating the immune response. 2. Influenza virus is a foreign pathogen that triggers the immune system to produce antibodies. 3. Cancer cells can be recognized as foreign and targeted by the immune system. 4. Choice D is correct because all options (A, B, and C) can provoke an immune response due to tissue damage, pathogens, or abnormal cells.

Correct Answer: D

Rationale: The correct answer is D: intrapleural pressure. Intrapleural pressure refers to the pressure within the pleural cavity, which is the space between the lungs and chest wall. This pressure is lower than atmospheric pressure, allowing the lungs to remain inflated. In space labeled '4', the pressure should be intrapleural pressure since it represents the pleural cavity. A: Alveolar pressure is the pressure within the alveoli of the lungs, not in the pleural cavity. B: Interpleural pressure is not a term commonly used in respiratory physiology. C: Subalveolar pressure is not a recognized term in respiratory physiology.