Question

Branched veins with flowing protoplasm occur in
A. Acellular Slime Moulds
B. Cellular Slime Moulds
C. Polysiphonia
D. Ulva

Answer 1

Veins are fine tubular structures through which fluid flows inside the body of an organism. Branched veins are further extensions of veins that form a fine network that spreads in a fan-like manner. Tubifera and Physarum are examples of organisms that show branched veins with flowing protoplasm.

Complete answer: The protoplasm of an organism refers to the living part of the cell. Protoplasm is also defined as the bodily fluid consisting of cells and various other components of the body suspended in a liquid. This fluid can be blood or any other transporting tissue. The blood vessels that transport blood towards the heart are called veins. These are fine tubular structures that are present throughout the organism’s body to filter the flowing protoplasm. Veins are sometimes further branched meaning that they split into fine networks forming a mesh-like structure resembling a fan.
Slime moulds exhibit veins in which protoplasm flows throughout the body. The slime moulds are classified under Protists. They resemble fungi as well as protozoa. These are mainly of two types. Acellular slime moulds are a mass of protoplasm. They are able to grow up to I ft in diameter. They are found over leaf litter, moist and decaying logs as a creeping slimy mass. They are decomposers as they feed on dead and decaying organic matter. Tubifera and Physarum are examples of acellular moulds. These moulds are eukaryotic organisms and are capable of surviving as single cells. They have branched fan-like veins as a front sheet. Protoplasm flows through these branched veins. The cellular moulds also have protoplasm flowing in their veins but they do not have branched veins.
Hence, the right answer is option A.

Note: The drying fruiting bodies of acellular moulds bear sporangia. Spores are formed inside sporangia that are extremely resistant to harsh conditions. The spores germinate and form haploid cells in moist conditions. Further, they form a slimy mass that produces beneficial chemicals. Some of the moulds are used for medicinal purposes and are economically important.