Correct option is B
Explanation:
● The Hershey–Chase experiment was conducted in 1952 using bacteriophages.
● They labelled DNA with radioactive phosphorus (³²P) and proteins with sulfur (³⁵S).
● Only DNA entered the bacterial cell, proving DNA is the genetic material.
Information Booster:
● Conducted by Alfred Hershey and Martha Chase.
● Used T2 bacteriophage infecting E. coli.
● Built on Griffith’s transformation experiment.
● Confirmed Avery, MacLeod, and McCarty’s 1944 findings.
● Earned Hershey a share of the 1969 Nobel Prize.
● Discovered by Friedrich Miescher in 1869.
● Double-helix structure was proposed by Watson & Crick (1953).
● DNA is made of nucleotides (sugar + phosphate + nitrogen base).
● Nitrogen bases: A, T, G, C (A–T & G–C pairing).
● DNA is found mainly in the nucleus; small amount in mitochondria.
● Carries genetic instructions for growth, development, and heredity.
● DNA replication is semi-conservative (proved by Meselson–Stahl experiment).
● Human DNA has about 3 billion base pairs.