Question

Assertion: In Porifera, archaeocytes are totipotent
Reason: They give rise to cells.
(a) Both Assertion and Reason are correct. The reason is the correct explanation for Assertion.
(b) Both Assertion and Reason are correct. The reason is not the correct explanation for Assertion.
(c) The assertion is correct but Reason is incorrect
(d) The assertion is incorrect but Reason is correct

Answer 1

Hint: The amoeboid cells found in sponges are called archaeocytes. They are also termed as amoebocytes. Totipotency is the ability of cells that are capable of developing into complete new organisms.

Complete answer:
Archaeocytes are totipotent and have wide-ranging functions depending on the species. The structure of these cells is similar to that of the stem cells as it contains high cytoplasmic content that benefits the cells to transform according to their function.
- Archeocytes have the ability of totipotency and hence perform various functions depending on the species of the sponges.
- Archaeocytes, colonocytes, and other structural elements together form a structure called spicules.
- Archaeocytes float within the mesohyl with amoeba-like movements serving many important purposes.
- Cellular differentiation is an important function of the archaeocyte. All specialized cells present inside the sponge derive from the archaeocyte.
- The gametes are formed from archaeocytes which are an essential part of sexual reproduction. In asexual reproduction, archaeocytes lead to the formation of gemmules.
- In some species of sponges, archaeocytes develop into choanocytes and help in respiration and digestion.
So the correct answer is the option “Both Assertion and Reason are correct. The reason is the correct explanation for Assertion.”

Note: The sponges do not have systematized tissue. They have a cellular- level organization, that is their cells are specialized so that different cells aid in different functions, but similar cells are not arranged into tissues are a sort of loose clumps of different kinds of cells. They depend on these specialized cells, such as choanocytes, porocytes, archaeocytes, and pinacocytes, for specialized functions within their bodies. The mesohyl serves as a type of endoskeleton and helps to maintain the tubular shape of sponges.