Which of these is an early symptom of rabies

Correct Answer: D

Rationale: The correct answer is D because all of the symptoms mentioned (short period of depression, nausea, restlessness) can be early signs of rabies. Rabies typically presents with a variety of non-specific symptoms in the early stages, including behavioral changes such as depression and restlessness, as well as gastrointestinal symptoms like nausea. Therefore, it is important to consider the combination of these symptoms collectively rather than individually when suspecting rabies. Choices A, B, and C alone may not definitively indicate rabies, but when seen together, they should raise suspicion and prompt further evaluation and testing for rabies.

Correct Answer: A

Rationale: The correct answer is A: Capsule. The capsule is a mucous structure tightly bound to the bacterial cell wall. It helps bacteria evade the host immune system and provides protection. The other choices are incorrect because: B) Spores are resistant structures formed by some bacteria for survival, C) Flagella are long, whip-like structures for movement, and D) Filaments are long, thin structures found in some bacteria.

Correct Answer: B

Rationale: The correct answer is B because the presence of calcium dipicolinate in bacterial spores helps protect their DNA from damage under harsh conditions. Calcium dipicolinate acts as a stabilizer, preserving the spore structure. Choice A is incorrect as bacterial spores have a tough protein coat, not a lipid-rich membrane. Choice C is incorrect as bacterial spores have very low metabolic activity. Choice D is incorrect as bacterial spores have low water content to prevent damage during harsh conditions.

Correct Answer: C

Rationale: The correct answer is C: ensure survival under harsh conditions. Bacterial endospores are dormant, resistant structures that form under adverse conditions to protect the bacterial DNA and allow the bacterium to survive extreme environments. This function is crucial for the bacterium's long-term survival. Choice A is incorrect as endospores do not directly produce exotoxins. Choice B is incorrect as endospores do not store nutrients but rather protect the bacterium's genetic material. Choice D is incorrect as endospores do not enhance motility but rather enable survival during unfavorable conditions.

Correct Answer: B

Rationale: The correct answer is B: peptidoglycan and calcium dipicolinate. Bacterial endospores are resistant structures formed by certain bacterial species under unfavorable conditions. Peptidoglycan provides structural support, while calcium dipicolinate aids in heat resistance. Lipid bilayers (choice A) are not a primary component. Capsular polysaccharides (choice C) are part of the bacterial capsule, not the endospore. Teichoic acid (choice D) is a component of the cell wall, not the endospore.