Moss Life Cycle Diagram

Questions and Answers

What is unique about the roots of mosses?

They are absent or non-existent. (correct)

They are only found in male mosses.

They are vascular and transport nutrients.

They are deep and spread out widely.

What is the term for the switch between haploid and diploid life stages in mosses?

Haploid-Diploid Cycle

Alternation of Generations (correct)

Alternation of Reproduction

Diploid-Haploid Transition

What is the function of antheridia in mosses?

To produce male gametes (correct)

To produce female gametes

To produce flowers

To produce spores

What is the life stage of mosses that involves asexual reproduction?

Diploid Signup and view all the answers

What is the term for the mature moss plants that can be either male or female?

Gametophytes Signup and view all the answers

What is the main function of gametophytes in mosses?

To undergo photosynthesis and make food for the plant Signup and view all the answers

What is the result of fusion between sperm and egg in mosses?

A zygote Signup and view all the answers

What is the significance of the letter 'n' in the study of reproduction and genetics in mosses?

It represents one set of chromosomes Signup and view all the answers

What is a characteristic of nontracheophytes, which include mosses?

They use other systems to uptake and deliver water needs Signup and view all the answers

What is the term for the process of change between gametophytes and sporophytes in mosses?

Alternation of generations Signup and view all the answers

What is the main function of the antheridium in moss reproduction?

To produce sperm Signup and view all the answers

What is the term for the process by which the zygote splits into two identical cells in the moss life cycle?

Mitosis Signup and view all the answers

What is the purpose of the calyptra in moss reproduction?

To protect the forming capsule Signup and view all the answers

What is the term for the type of reproduction that involves gametes from two parents in moss?

Sexual Signup and view all the answers

What is the dominant generation in the life cycle of mosses?

Gametophyte Signup and view all the answers

Study Notes

Moss Life Cycle

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.

Haploid Stage (Gametophyte)

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.

Diploid Stage (Sporophyte)

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.

Alternation of Generations

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.

Reproduction in Mosses

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.

Parts of Moss

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