Life Cycle of Pterophytes (ferns)

Question 1

What life cycle do Pterophytes follow?

Answer 1

They are vascular plants that reproduce through spores rather than seeds.
They have a dominant sporophyte generation and an independent smaller gametophyte generation.
Their reproductive cycle follows the alternation of generations, which includes both haploid (n) and diploid (2n) stages.

Question 2

What happens during the sporophyte generation (Diploid-2n)

Answer 2

-The dominant, large, leafy fern plant.
-Produces spores in structures called sporangia, which are grouped into clusters called sori.
-each spore is haploid (n) and develops into gametophyte.

Question 3

What happens during the gametophyte generation (Haploid-n)

Answer 3

-A small heart shaped =, independent = plant called a prothallus.
-Produces antheridia (male structures) that make sperm and archegonia (female structures) that produce eggs.
-Fertilization occurs when sperm swim through water to reach the egg forming a new diploid sporophyte.

Question 4

What is the sporangia and sori reproductive structure?

Answer 4

-Sporangia: Tiny capsules that contain haploid spores.
-They are found in clusters called sori on the underside of fern fronds (leaves)
-When mature, sporangia burst open, releasing spores into the environment.

Question 5

What is the prothallus reproductive structure?

Answer 5

-It is a small, green, heart shaped structure that develops from a spore.
-It contains Antheridia and Archegonia.

Question 6

What is required for defendant fertilization?

Answer 6

-Water because motile sperm swim to the egg.
-Once the sperm reaches the egg inside the archegonium, fertilization occurs, forming a diploid zygote.

Question 7

What happens during sporophyte generation?

Answer 7

-Zygote develops into an embryo, which grows into a mature sporophyte.
-The young sporophyte develops leaves and roots, eventually becoming the dominant fern plant.