According to _____________ protoplasm is the physical basis of life.

Hint: Inside the cell wall of a living cell the living substance is known as protoplasm. The cell wall is a non-living substance. The cell membrane, nucleus, and cytoplasm together form protoplasm.

Complete answer:
The correct answer to be filled in the blank is Huxley. He was the scientist who believed protoplasm is the physical basis of life.
Thomas Henry Huxley (4 May 1825 – 29 June 1895) was an English biologist and anthropologist specializing in comparative anatomy. Sometimes, protoplasm is used as a general term for cytoplasm. But, that’s not true as protoplasm is a substance that constitutes the living the nucleus, the cytoplasm, plastids, and mitochondria of the cell. If we look closely protoplasm is the jelly-like, colorless, transparent, and viscous living substance present inside the cell wall.
Therefore, it also surrounds the cell membrane, unlike the cytoplasm. The term protoplasm was first proposed in 1835 and it also helps in various life processes. Talking about the initial component of protoplasm it is cytoplasm which is found between the cell membrane and cell nucleus in the eukaryotic cell, a nucleus is only present in the eukaryotic cell.
Whereas, in the prokaryotic cell the cytoplasm is a gel-like substance in which other cell components are suspended. The second component which is present in protoplasm is the nucleus which contains all the genetic information. Proteins, fats, enzymes, hormones, all make up the protoplasm.

Note: The term cytoplasm, nucleus, and organelles are more relevant to describe the structure of the cell. “Protoplasm” is a vague term and is not used in modern biology anymore.