Moss Life Cycle Diagram

Study Notes

Mosses are non-vascular plants belonging to Phylum Bryophyta that tend to live in moist environments.
They have two life stages: haploid and diploid, both of which are multicellular.
The haploid stage is responsible for sexual reproduction, while the diploid stage is responsible for asexual reproduction.
This change between haploid and diploid is known as the alternation of generations.

The haploid stage is the dominant stage in the moss life cycle, where the plant is either male or female.
Mature females have archegonia, which holds the female gametes, reproductive organs, and is where the egg is located.
Mature males have antheridia, which holds the male gametes, reproductive organs, and is where the sperm are located.
Sexual reproduction occurs in the haploid stage, where sperm meets an egg and results in a zygote.

The diploid stage is responsible for asexual reproduction, where the plant contains two sets of chromosomes.
The sporophyte is the structure responsible for asexual reproduction and is more pod-shaped.
The sporophyte needs the gametophyte to support it.
The sporophyte produces spores through meiosis, which are genetically diverse and will grow into new gametophytes.

The change between the haploid and diploid stages is known as the alternation of generations.
The alternation of generations starts with the fusion of sperm and egg, resulting in a zygote.
The zygote then undergoes mitosis, resulting in a sporophyte, which produces spores.
The spores then germinate and grow into new gametophytes, starting the cycle again.

Mosses have two types of fertilization processes: sexual and asexual.
Sexual reproduction involves a male and female gamete, while asexual reproduction involves only one plant.
The sexual reproduction phase includes gametophytes, which are the dominant stage in the moss life cycle.

Antheridial head: holds the antheridium and eventually creates the sporangium
Antheridium: produces sperm
Archegonial head: produces eggs
Bud: small, germinated spores
Capsule: holds the spores
Calyptra: protection over a forming capsule
Early Embryo: pre-zygote cells, can be called germination or fusion
Egg/Archegonium: where fertilization takes place, the female gamete
Foot: helps to give nutrients to sporophyte
Germinating spore: spores that have taken hold and will become new plants
Leaves: produce photosynthesis, collect water
Neck canal: route for sperm to travel for reproduction
Neck wall: creates neck cavity
Operculum: breaks when spores are ready to leave and germinate
Protonema: hormones for new cellular growth
Rhizoids: specialized root-like structure, they anchor the moss but do not absorb water like roots of other plants
Seta: helps transfer nutrients throughout the flower
Sperm/Antheridium: male gamete
Spores: type of reproduction from the sporophyte
Spore case: holds spores
Sporophyte: creates the spores
Venter: holds the egg
Venter wall: creates the venter cavity
Zygote: single-celled organism created after fusion of the egg and sperm

Podcast