Seedless Plants

What mutualistic relationship was crucial for early land plants to establish themselves in terrestrial habitats?

Associations with fungi, which helped with nutrient and water absorption from the soil.

In the phylogeny of green plants, which group is typically recognized as the outgroup?

Red Algae

What are the two main evolutionary groups of land plants?

Bryophytes and Tracheophytes.

What key derived character separates Tracheophytes from Bryophytes?

The presence of vascular tissue (tracheids).

What are the two types of vascular tissue found in tracheophytes?

Xylem and phloem.

What is the primary function of xylem in vascular plants?

It transports water and dissolved minerals from the roots to the rest of the plant.

What is the primary function of phloem in vascular plants?

It transports sugars, amino acids, and other organic products from where they are made to where they are needed.

Do Bryophytes possess true vascular structures like xylem and phloem?

No, they lack true vascular tissue.

Haplodiplontic life cycle

A life cycle, also known as alternation of generations, that includes both a multicellular diploid stage (sporophyte) and a multicellular haploid stage (gametophyte).

In a haplodiplontic life cycle, what is the ploidy level of the sporophyte generation?

Diploid (2n)

In a haplodiplontic life cycle, what is the ploidy level of the gametophyte generation?

Haploid (n)

The sporophyte produces _____ through the process of meiosis.

spores

What is the function of the sporophyte in the haplodiplontic life cycle?

To produce haploid spores through meiosis.

What is the function of spores in the haplodiplontic life cycle?

To germinate and grow into a multicellular haploid gametophyte via mitosis.

The gametophyte produces _____ through the process of mitosis.

gametes

What is the function of the gametophyte in the haplodiplontic life cycle?

To produce haploid gametes through mitosis.

What process follows the fusion of gametes (fertilization) in a haplodiplontic life cycle?

The formation of a diploid zygote, which develops into the sporophyte.

Which cellular division process generates haploid spores from a diploid sporophyte?

Meiosis

Which cellular division process generates haploid gametes from a haploid gametophyte?

Mitosis

Arrange the following structures in the correct order for a haplodiplontic life cycle, starting with the sporophyte: gametophyte, spores, gametes, sporophyte.

Sporophyte -> spores -> gametophyte -> gametes.

Which generation is dominant in the Bryophyte life cycle?

The gametophyte generation.

How does the sporophyte relate to the gametophyte in Bryophytes like mosses?

The sporophyte is dependent on and lives on the surface of the larger, dominant gametophyte.

Which generation is dominant in the Tracheophyte life cycle?

The sporophyte generation.

What is the major evolutionary trend regarding the gametophyte in Tracheophytes (and seed plants)?

The gametophyte becomes significantly reduced in size and is often dependent on the sporophyte.

Comparing Bryophytes and Tracheophytes, what is the evolutionary trend concerning the sporophyte generation?

The sporophyte generation becomes larger, more complex, and dominant over the gametophyte.

Key innovations of _____, such as vascular tissue, are derived characters that differentiate them from Bryophytes.

Tracheophytes (vascular plants)

Discuss one key ecological consequence of the evolution of vascular tissue in Tracheophytes.

It allowed plants to grow taller, competing more effectively for sunlight and dispersing spores over greater distances.

Discuss a key ecological consequence of the characteristics possessed by Bryophytes

Their lack of vascular tissue restricts them to small sizes and typically moist environments.

What is the term for plants that possess vascular tissue, specifically tracheids?

Tracheophytes.

What structure is produced by the fertilization of an egg by a sperm in the land plant life cycle?

A diploid zygote.

The diploid zygote develops into the multicellular _____ through mitosis.

sporophyte

What is the ploidy level of gametes in the haplodiplontic life cycle?

Haploid (n).

What is the ploidy level of spores in the haplodiplontic life cycle?

Haploid (n).

Rhizomes

Charophytes