Question

Which of the following is correctly categorized?

• A. Calcitonin and Thymosin → Thyroid Hormones
• B. Secretin and Rhodopsin → Polypeptide Hormones
• C. Troponin And Myosin → Complex Proteins In Striated Muscles
• D. Pepsin and Prolactin → Digestive Enzymes Secreted In Stomach

Answer 1

The correct option is C

Troponin And Myosin → Complex Proteins In Striated Muscles

The correct option is C.

Explanation for correct option:

1. Troponin and Myosin are complex proteins.
2. These proteins are found in striated muscles.
3. They aid in the contraction of muscles.
4. The muscles of the heart contain troponins. Troponin enters the circulation whenever the heart suffers injury.
5. Myosin is the model for a molecular motor i.e. it is a protein that transforms chemical energy (ATP) into mechanical energy to produce movement and force in skeletal muscles.

Explanation for incorrect options:

Option A:

1. The hormone called thymosin, which is secreted by the thymus, aids in promoting the formation of certain immune cells.
2. Another hormone secreted by the thyroid gland's parafollicular cells is called calcitonin.
3. Calcitonin and Thymosin are not thyroid hormones.

Option B:

1. A vitamin D derivative is Rhodopsin.
2. A hormone called secretin is released into the circulation by the duodenum to promote liver and pancreatic secretion (particularly in reaction to acidity).
3. Secretin and Rhodopsin together are not Polypeptide Hormones.

Option D:

1. The pituitary gland releases a hormone called prolactin.
2. A hormone that aids in protein digestion, pepsin is released in the stomach.
3. Pepsin and Prolactin together are not the digestive enzymes secreted in the stomach.

Final answer: The pair Troponin And Myosin → Complex Proteins In Striated Muscles is correctly categorized.