Is this pain or pure genius

Group of genes that encode molecules found in all body cells, creating a biochemical “fingerprint” that serves as the “id” for cells so that they are marked as “self” a) deoxyribonucleic acid (dna) b) entry inhibitors c) major histocompatibility complex (mhc) d) non-nucleoside reverse transcription inhibitors (nnrtis)

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1. controls how much sugar is in the blood pancreas 2. controls the other glands pituitary gland 3. manufactured by the brain to relieve pain thyroid 4. gland that regulates the body's energy levels endorphins