Answer: The lock-and-key mechanism is usually associated with the complementary shapes of an enzyme with a single substrate wherein the lock that is being referred to is the enzyme and the substrate is the key. One right sized substrate (key) fits into the active site (key hole) of the enzyme (lock).
Calcium deficiency disease (hypocalcemia) --- like osteoporosis, osteopenia !!
Answer:
Phoebus Levene( 1896, Sagor Russia - Septemeber 1940, New York)
Explanation:
These were developed by Phoebus Aaron Theodor Levene ,he was a russian who studied medicine, with keen interest in organic chemistry.
He migrated to the US in 1891, and started practising medicine in 1892.Due to his strong interest in research he combined research(1894) in molecular structure of sugars with medical practice,But this was cut short when he contracted tuberculosis.
Between 1896- 1906,he collaborated with many nucleic acids and protein exoperts e.g Albrecht Kossel and Emil Fischer to wok on the structure of DNA.And headed the Rockefeller Institute for Medical Research.
He works included :the isolation of Nucleotide-monomers of DNA
:the isolation of D-ribose sugar from ribonucleic acid molecule.(RNA)
Discovery of 2-deoxyribonucleic ,
How the components of Nucleotide(phosphate group,sugars, and organic bases) combined to form nucleotide, and how the latter undergo condensation reaction to form DNA.
