Ringworm is caused by a____
a. helminth
b. dermatophyte
c. dimorphic fungus
d. commensal fungus

Verified step by step guidance

1. Understand the term 'ringworm': It is a common fungal infection of the skin, not caused by a worm despite its name.
2. Identify the characteristics of each option: a helminth is a parasitic worm, a dermatophyte is a type of fungus that causes skin infections, a dimorphic fungus can exist in two forms, and a commensal fungus lives in harmony with the host without causing disease.
3. Recall that ringworm is characterized by red, circular, itchy rashes on the skin.
4. Consider the typical causes of skin infections: Dermatophytes are known to cause infections of the skin, hair, and nails, including ringworm.
5. Conclude that the most likely cause of ringworm, based on the options provided, is a dermatophyte.

Key Concepts

Dermatophytes

Dermatophytes are a group of fungi that specifically infect keratinized tissues such as skin, hair, and nails. They thrive in warm, moist environments and are responsible for common skin infections, including ringworm. Understanding dermatophytes is crucial for identifying the causative agents of these infections and their treatment.

Fungal Infections

Fungal infections, or mycoses, occur when fungi invade and multiply in the body, leading to various health issues. These infections can be superficial, like ringworm, or systemic, affecting internal organs. Recognizing the type of fungus involved is essential for effective diagnosis and treatment.

Pathogenicity of Fungi

Pathogenicity refers to the ability of an organism to cause disease. In the context of fungi, certain species have evolved mechanisms to invade host tissues and evade the immune system. Understanding the pathogenicity of dermatophytes helps in comprehending how they cause infections like ringworm and informs treatment strategies.