[Campbell Biology P.652] Based on the life cycle diagram of Laminaria Figure 28.14 and the "... | Practice Question

Based on the life cycle diagram of Laminaria Figure 28.14 and the "Visual Skills" prompt, are the sperm shown in step 5 genetically identical to one another? Explain your reasoning.

  • A3: Yes, because male gametophytes produce sperm through mitosis, which ensures genetic identity.
  • B3: No, because the zoospores, from which the male gametophytes develop, are produced by meiosis, introducing genetic variation.
  • C3: Yes, because all cells produced in sexual reproduction are genetically identical before fertilization.
  • D4: No, because sperm and eggs are always genetically distinct, even from the same parent.

Explanation

The male gametophytes develop from haploid zoospores Step 4 , which are produced by meiosis from the diploid sporophyte Step 3 . Meiosis introduces genetic variation. Therefore, while individual male gametophytes produce genetically identical sperm by mitosis, different male gametophytes originating from different zoospores will produce genetically distinct sperm. The question refers to 'the sperm shown in 5' which implies a general population of sperm, hence they are not genetically identical.