What is meant by haploid gametophytes

Biologists and botanists

Oh, it was a long time ago.

We start with the gametophyte. This grows from a haploid spore (i.e. it only has a single set of chromosomes). This develops sexual organs in which the gametes (germ cells) mature. In humans, that would theoretically be the egg cell and the sperm (also both haploid).
Two gametes fuse to form a diploid (= double set of chromosomes, each from one of the partners) zygote, from which the sporophyte then matures (in humans, the zygote would be the fertilized egg cell)

The resulting sporophyte is then used for the formation and spread of spores. These arise from diploid mother cells of the sporophyte. However, through reduction division (meiosis), the spores that arise are haploid again.
These spores are released into the environment and serve to spread the plant via wind, water, animals, etc. A new gametophyte can emerge from each spore and the cycle begins again

This means that the genetic material is mixed in two places:
- Formation of the spores in the sporophyte (random division of the parental diploid set of chromosomes into two haploid spores)
- Merging of two gametes into a new diploid set of chromosomes

The sense and purpose of the whole game, like us humans, is the spread of the plant and the mixing of the genetic material. Just that the plants do it in a slightly different way than we do

The difference between gametophyte and sporophyte is possessed by mosses, ferns and bed covers. Only that in the course of evolution the gametophyte has become more and more inconspicuous:

In mosses, the haploid gametophytes are the small green plants on the ground. The sporophytes usually grow from it like a stalk.

In ferns, the gametophyte is rather inconspicuous and is called prothallium. The large green fern fronds already represent the sporophytes!

In angiosperms, the gametophyte consists only of the male sex cells (pollen grain) and the female sex cells (embryo sac)