Assertion (A): Mitochondria are called semi-autonomous organelles. Reason (R): They possess their own DNA and ribosomes and can synthesize some proteins. MCQ with Answer and Explanation

Explanation:
Insulin-like Growth Factor 1 (IGF-1), also known as somatomedin C, is a peptide hormone structurally similar to insulin. It is primarily synthesized and secreted by the liver (and to a lesser extent by other tissues) in response to stimulation by Growth Hormone (GH). IGF-1 mediates most of the growth-promoting (anabolic) effects of GH. It stimulates the proliferation and differentiation of chondrocytes (cartilage cells) in the epiphyseal plates of bones, promotes protein synthesis in muscles, and supports the growth of various other tissues.

Explanation:
George Beadle and Edward Tatum, working with Neurospora crassa, proposed that each gene controls the synthesis of a specific enzyme (later refined to one gene-one polypeptide). Watson and Crick discovered DNA structure, Hershey-Chase confirmed DNA as genetic material, Meselson-Stahl demonstrated semi-conservative replication.

Explanation:
The cerebellum, located at the back of the brain, integrates sensory input and fine-tunes motor activity, posture, and equilibrium. The cerebrum handles conscious thought and voluntary actions, the thalamus relays sensory information, the medulla controls vital autonomic functions like breathing and heart rate.