Moss Life Cycle

Alternation of generationsZygote created from egg & sperm

Alternation of generationsZygote divides by mitosis to create adult sporophyte

Alternation of generations

Haploid spores created by meiosis

Alternation of generations

Haploid spores released into air

Alternation of generations

Female gametophyte creates eggs

Male gametophyte creates sperm

Spore grows into male or female gametophyte

Alternation of generations

Sperm & egg create diploid zygote

Alternation of generationsCycle repeats

Group 1: Seedless, Nonvascular Plants

• Most primitive of plants

• Live in moist environments– Swimming sperm

• Examples:– Liverworts– Hornworts– Mosses

Mosses• Because

nonvascular: Grow low to ground– Water transported by

simple diffusion

• Lack true leaves– only 1 cell thick

• Rhizoids anchor into soil

• Early inhabitant of new ecosystems (succession)

Moss Life Cycle• Gametophyte stage

– Dominant stage; Haploid

– Looks like mat of green shag carpet

Moss Life Cycle• Gametophyte stage

– Dominant stage; Haploid

– Looks like mat of green shag carpet

• Antheridium: produces male sperm

Male gametophyte(creates sperm)

Moss Life Cycle• Gametophyte stage

– Dominant stage; Haploid

– Looks like mat of green shag carpet

• Antheridium: produces male sperm

• Archegonium: produces female egg

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

Moss Life Cycle• Gametophyte stage

– Dominant stage; Haploid

– Looks like mat of green shag carpet

• Antheridium: produces male sperm

• Archegonium: produces female egg

– Sperm swims through water to fertilize egg

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

Moss Life Cycle• Gametophyte stage

– Dominant stage; Haploid

– Looks like mat of green shag carpet

• Antheridium: produces male sperm

• Archegonium: produces female egg

– Sperm swims through water to fertilize egg

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygote

Moss Life Cycle

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygote

stalk

• Gametophyte stage– Dominant stage; Haploid

– Looks like mat of green shag carpet

• Antheridium: produces male sperm

• Archegonium: produces female egg

– Sperm swims through water to fertilize egg

• Sporophyte stage– Stalk grows out of the

zygote

Moss Life Cycle

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygote

capsule

stalk

• Gametophyte stage– Dominant stage; Haploid

– Looks like mat of green shag carpet

• Antheridium: produces male sperm

• Archegonium: produces female egg

– Sperm swims through water to fertilize egg

• Sporophyte stage– Stalk grows out of the

zygote

– Haploid spores created inside capsule by meiosis

Moss Life Cycle

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygote

capsule

stalk

• Gametophyte stage– Dominant stage; Haploid

– Looks like mat of green shag carpet

• Antheridium: produces male sperm

• Archegonium: produces female egg

– Sperm swims through water to fertilize egg

• Sporophyte stage– Stalk grows out of the

zygote

– Haploid spores created inside capsule by meiosis

– Spores released and grow into new gametophytes

.....

Moss Life CycleSee appendix B in your text book

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygote

capsule

stalk

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

. .

Moss Life CycleSee appendix B in your text book

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygote

capsule

stalk

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

Moss Life CycleSee appendix B in your text book

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygote

capsule

stalk

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

Moss Life CycleSee appendix B in your text book

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygote

capsule

stalk

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

Moss Life Cycle

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygote

capsule

stalk

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygotesporophyte

Moss Life Cycle

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

zygote

capsule

stalk

Male gametophyte(creates sperm)

Female gametophyte (creates eggs)

sporophyte....

Moss Life Cycle

Place the steps of the moss life cycle in order, from the step started for you:

__ 1___ Spores land._______ Diploid sporophyte will grow from zygote._______ Through water, sperm swim from

antheridium (male gametophyte) to archegonium (female gametophyte).

_______ Moss gametophytes grow near the ground._______ Sporophyte will create and release spores._______ Fertilization occurs.

Kobe Kuiz1) Label the parts of the diagram.

2) Using the picture answer the following:

• Where are spores created?• Name the haploid stage.• Which grows from the zygote?

3) How are the antheridia and archegonia different? Similar?

4) Meiosis begins which stage of plants?

5) Fertilization begins which stage of plants?

6) How are haploid spores created?