Question

5 LLLULU, UPILL 28.h. Are sperm haploid or diploid? Examine slide of moss life history (DO NOT DRAW) 28. i. What event begins the sporophyte phase of the life cycle? Where does this event occur in mosses and liverworts? 28. j. What event begins the gametophyte phase of the life cycle? Where does it occur in mosses and liverworts?

Answer 1

Ans 28 h: sperm is a haploid structure

Ans 28 i

Life cycles in plants/algae completes in two distinct phases namely gametophyte and sporophyte stage. Gametophyte is a haploid structure that produces male and female gametes whereas sporophyte is a diploid stage.

Male and female gametes fuses and forms zygote. From the zygote, sporophyte develops. Sporophyte is a multicellular diploid structure. Therefore, we can say that, the formation of the zygotes initiates the second phase of life cycle i.e. sporophyte phase

In mosses the fertilization occurs in archegonium. Archegonium is a female structure produces female gametes. Male gametes are produce by antheridium. Male gametes i.e sperm released from antheridium, swims in water and reaches to archegonia and fertilized the eggs and forms the zygote. The zygote develops into sporophyte.

Ans 28 j

The gametophyte stage starts from the haploid spore. The haploid spore germinates to protonema. Protonema develops into gametophore that contains the gametes. Archegonium and antheridium are the female and male organs that produces eggs and sperm respectively. The sperm releases from antheridium and reaches to the eggs in archegonium. Fertilization occurs and sporophyte stage starts.