Seedless plants

What evidence shows that plants and green algae evolved from a common ancestor?

Both share similar chlorophyll types, cell wall composition, and reproductive structures.

What is the evidence that plants are most closely related to the charophytic green algae?

Plants and charophytic green algae share similarities in DNA, chloroplasts, and cellular structures.

What charaacteristics set plants apart from the charophytic green algae?

Plants have adaptations for life on land, including protected embryos, specialized reproductive structures, cuticles in many groups, and alternation of generations.

What are the major challenges plants face when living on dry land?

• Preventing water loss and desiccation.

• Obtaining and transporting water and minerals.

• Reproducing without depending on free-standing water.

• Supporting the plant body against gravity.

What are the benefits of life on early land?

Early land offered abundant sunlight for photosynthesis, more available carbon dioxide, and fewer aquatic competitors and herbivores in some environments.

What is alternation of generations?

Alternation of generations is a life cycle in which a plant alternates between two multicellular stages: a haploid gametophyte and a diploid sporophyte

What is a sporophyte, and what is its nuclear condition?

A sporophyte is the diploid (2n), multicellular stage of a plant's life cycle.develops from a diploid zygote and produces haploid spores through meiosis.

What is a gametophyte, and what is its nuclear condition?

A gametophyte is the haploid (n), multicellular stage of a plant's life cycle.develops from a haploid spore through mitosis and produces gametes through mitosis.

What is a spore, and what is its nuclear condition?

A spore is a haploid (n) reproductive cell produced by a diploid sporophyte through meiosis. can develop into a gametophyte without fusing with another cell.

What is a gamete, and what is its nuclear condition?

gamete is a haploid (n) reproductive cell, such as a sperm or egg, that fuses with another gamete during fertilization to form a diploid zygote.

What is a zygote, and what is its nuclear condition?

A zygote is a diploid (2n) cell formed when a haploid sperm fuses with a haploid egg during fertilization. develop the sporophyte mitotic cell

What kind of cell division creates spores in plants?

Meiosis create haploid spores from diploid cells in the sporophyte.

What kind of cell division creates gametes in plants?

Mitosis creates gametes in plants.

What kind of cell division occurs when spores produce gametophytes and zygotes produce sporophytes?

Mitosis is for both types of cell division. Haploid spores divide by mitosis to form multicellular gametophytes, and diploid zygotes divide by mitosis to form multicellular sporophytes.

Describe the alternation of generations life cycle in order.

sporophyte (2n), Spores (n), Gametophyte (n), Sperm (n)+ Egg (n), Zygote (2)

What are the four basic plant groups?

Bryophytes, Seedless, Gymnosperms, Anigosperms

Do bryophytes have vascular tissue? How does this affect their size and habitats?

Bryophytes don’t have vascular tissue, including xylem and phloem. As a result, they usually remain small because water and nutrients must move mainly by diffusion or short-distance transport

How do bryophytes obtain water, and how does this affect their morphology, roots, habitats, and size?

Bryophytes absorb water across their surfaces and move it short distances through their tissues. They do not have true roots; instead, many have rhizoids that anchor them and may help with water absorption.

Why must bryophytes generally remain small?

Without vascular tissue, bryophytes cannot efficiently transport water and dissolved minerals throughout a large body.

Bryophytes lack roots and are small. What benefit does this provide, and what does it allow them to exploit?

Their small size and lack of true roots allow them to grow on surfaces such as rocks, tree bark, soil, and other areas where larger plants may not easily establish. colonize exposed or nutrient-poor surfaces and absorb water

What does it mean that bryophytes are poikilohydric?

Poikilohydric organisms cannot maintain a constant internal water content.

Bryophytes may dry out during unfavorable conditions and become metabolically inactive, then resume activity when water becomes available.

How does poikilohydry influence bryophyte biology, and what desiccation strategy does it represent?

It means that bryophytes can tolerate a wide range of hydration levels, allowing them to survive in fluctuating water conditions.

Which phase of the bryophyte life cycle is dominant?

The gametophyte phase is dominant, representing the main form of the plant and facilitating reproduction.

Is the bryophyte sporophyte dependent or independent?

the bryophyte sporophyte is dependent on the gametophyte for nutrition

What is required for bryophyte sperm to reach the egg?

water / flies The sperm swim through water from the male reproductive structure to the egg inside the female reproductive structure.

Describe a bryophyte spore. What are the benefits of bryophytes have small, light spores? How do they

A bryophyte spore is a small, haploid reproductive cell produced by meiosis in the sporophyte. It can develop into a new gametophyte.

Small, lightweight spores:

• Require relatively few resources to produce.

• Can be carried by wind.

• Can travel long distances.

• Help bryophytes colonize new habitats.

What are some ecological roles of bryophytes?

• Help colonize bare surfaces.

• Contribute to soil formation.

• Reduce soil erosion.

• Retain moisture.

• Provide habitats for small organisms.

What derived trait distinguishes ferns, gymnosperms, and angiosperms from bryophytes?

They have vascular tissue, which consists of specialized tissues that transport water, minerals, and sugars throughout the plant.

What are the functions of vascular tissue and how is the function of xylem different from the function of phloem?

• Xylem — transports water and dissolved minerals.

• Phloem — transports sugars and other organic nutrients

erns (and allies) have vascular tissue, how does this affect their potential size and the degree to which they can be metabolically active.

Vascular tissue allows ferns to transport water and nutrients to photosynthetic tissues and distribute sugars to other parts of the plant. This supports greater growth and metabolic activity than would generally be possible in a similarly sized nonvascular plant.

How does vascular tissue affect the size of ferns and other vascular plants?

Vascular tissue allows plants to transport water, minerals, and sugars efficiently over greater distances.

How does vascular tissue affect the metabolic activity of ferns?

Vascular tissue allows ferns to transport water and nutrients to photosynthetic tissues and distribute sugars to other parts of the plant.

What is a sporophyll?

A sporophyll is a leaf or leaflike structure that bears sporangia, the structures where spores are produced.

Which of the four major plant groups have true leaves?

• Bryophytes: Do not have true leaves, although some have leaflike structures.

• Seedless vascular plants: Have true leaves in groups such as ferns.

• Gymnosperms: Have true leaves, such as pine needles.

• Angiosperms: Have true leaves.

Someone tells you that bryophytes must live in moist places, how would you respond?

Bryophytes are commonly found in moist environments because they absorb water across their surfaces and require water for sperm to swim to the egg. However, they do not all need to live in permanently wet places.

Name this organism

Antheridia

name this organism

sporangia

name this organism

Moss Archeginial

name this organism

Gametophyte Prothallus