[Campbell Biology P.827] According to the passage and Figure 35.30, what is a crucial determ... | Practice Question

According to the passage and Figure 35.30, what is a crucial determinant for an Arabidopsis epidermal cell to develop into a root hair cell?

  • A: The epidermal cell borders a single cortical cell and expresses GLABRA-2.
  • B: The epidermal cell borders two cortical cells and does not express GLABRA-2.
  • C: The epidermal cell is part of the root cap and will be sloughed off.
  • D: The epidermal cell is in contact with any number of cortical cells and expresses MADS-box proteins.

Explanation

The passage states: 'The immature epidermal cells that are in contact with two underlying cells of the root cortex differentiate into root hair cells, whereas the immature epidermal cells in contact with only one cell in the cortex differentiate into mature hairless cells.' It further clarifies that GLABRA-2 is 'not expressed' when an epidermal cell borders two cortical cells, leading to root hair development.