Lecture: Plants Diversity (Chapter 30)

Gametophyte, Monocot vs. Dicots, Life Reproduction Cycle

Fill in the blank

The multicelluar _____ is haploid and produces haploid gametes by ____

gametophyte; mitosis

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The process of _______ is when male and female gametes fuse together. They form a diploid zygote that will eventually grow into a _______

fertilization; sporophyte

What is a sporophyte?

The sporophyte is the diploid phase of the plant life cycle that develops from the zygote and produces haploid spores through meiosis. It is typically the dominant stage in vascular plants.

By which process do sporophytes produce haploid spores?

Through meiosis.

Study the reproductive cycle

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Ancestral species gave rise to land plants which can be informally grouped based on the presence or absence of _____ tissue

vascular

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Nonvascular plants are commonly called _____.

bryophytes a group consisting mainly of mosses and liverworts.

What do vascular plants have that differentiate them form bryophytes?

Vascular tissue

Are vascular plants seedless?

Some vascular plants are seedless, such as ferns.

What is a seed comprised of?

A seed is comprised of an embryo, a supply of nutrients, and a protective seed coat.

What 2 clads are seeded plants divided into?

gymnosperm and angiosperm

Why are gymnosperms called naked seeds?

Gymnosperms are called naked seeds because their seeds are not enclosed in an ovary or fruit, but rather develop on the surface of cone scales. This exposure allows for direct fertilization and dispersal, distinguishing them from angiosperms.

What is the sex organ for a gymnosperm?

The sex organ for a gymnosperm is the cone, which is differentiated into male cones that produce pollen and female cones that develop seeds. The male cones produce pollen, while female cones are responsible for seed development.

What is the sex organ for an angiosperm?

The sex organ for an angiosperm is the flower, which contains stamens (male organs producing pollen) and carpels (female organs containing ovules).

Fill in the blank

Vascular plants have 2 types of vascular tissue:

______ and ______

xylem and phloem

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______ conducts water and minerals and is made of dead cells called tracheid

Xylem

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______ are living cells that distribute sugars and amino acids

Phloem are the vascular tissues responsible for transporting nutrients throughout the plant.

What is the function of the roots?

Root anchor vascular tissue of the plant and transports water, nutrients, and carbohydrates between the roots and the rest of the plant.

What is the function of the leaves?

increase surface area for capturing more solar energy used for photosynthesis

Fill in the blank

______ and ______ grains are key adaptation for life on land

Pollen and seed

What does an seed consist of?

embryo and nutrients that are surrounded by a protective coating

what parts does an ovule consist of?

megasporangium, megaspore, and a protective integument

Fill in the blank

A ___ ovule becomes a seed

fertilized

How many integuments do gymnosperm megaspores have?

Gymnosperm megaspores typically have one integument.

How many integuments do angiosperms megaspores have?

Angiosperm megaspores typically have two integuments.

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______ develop into pollen grains which contain the male gametophytes

Microspores

What occurs during pollination?

Pollination is the process by which pollen grains are transferred from the male to the female part containing ovules, leading to fertilization.

read

•Pollen eliminates the need for a film of water and can be dispersed great distances by air or animals.

describe the process of gymnosperm fertilization

Gymnosperm fertilization involves the transfer of pollen to the ovule, where sperm nuclei fertilize the egg, leading to the formation of seeds.

look

What are some evolutionary advantages that seeds have in comparison to spores?

they can remain dormant for long periods of time until conditions are favorable for germination. They can also be transported for long distances

True or False

A seed coat comes from a seeds integument once the ovules is fertilized

TrueA seed coat is formed from the integument of the ovule after fertilization, providing protection to the seed.

Read

The gymnosperms have "naked" seeds not enclosed by ovaries and exposed on modified leaves-cones

What are the 4 gymnosperm phyla?

1. Cycadophyta (Cycads)

2. Gingkophyta (Ginkgo bioloba)

3. Gnetophyta ( Gnetum, Ephedra,Welwitschia)

4. Coniferophyta (conifers)

Fill in the blank

Seed plants can divided into 2 clads:

______ and ______

Angiosperms and gymnosperms

What kinds of gymnosperms dominate northern latitudes?

cone-bearing gymnosperms called conifers

What the phylum that consists a single living species of?

Ginkgo biloba

True or False

The Ginkgo biloba has a high tolerance to pollution

True

What is the largest phylum in the gymnosperm phyla?

The largest phylum in gymnosperms is the Coniferophyta, which includes conifers like pine, spruce, and fir.

True or False

Confers are not green yearounds and can only can photosynthesis in the spring

False, conifers are green year-round and can photosynthesize throughout the year.

What are 3 key features of the gymnosperm life cycle?

the sporophyte generate dominates

the transfer pf sperm to ovules by pollen

development of seeds form fertilized ovules

Fill in the blank

Angiosperms are seed plants with reproductive structures called ______ and ______

flowers and fruits

What is the phylum for the flowering plants?

Anthophyta

Read

The flower is an angiosperm structure specialized for sexual reporduction. It is a specialized shoot w/ up to 4 types of modified leaves

sepals (enclose the flower)

petals (brightly colored and attract pollinators)

stamen (produce pollen on their terminal anthers)

carpels (consist of an ovary containing ovules at the base and a style holding p a stigma where pollen is received

True or false

Fruit typically consists of a mature ovary

True

True or false

Fruits do not aid seeds in any way

False fruit protects seeds and aid in seed dispersal

Read

Fruit adaptation help disperse seeds by wind, water, or animals

True or false

The flower of the sporophyte is composed of both male and female structures

True, as flowers contain stamens (male) and carpels (female) for reproduction. This allows for pollination and fertilization.

Fill in the blank

Male ______ are contained w/in ______ grains produced by the microsporangia of anthers

gametes; pollen

Read

•The female gametophyte  = embryo sac, develops within an ovule contained within an ovary at the base of a stigma.

How do flowers ensure cross-pollination between flowers from different plants of the same species?

Flowers often have mechanisms such as varying flowering times, distinct morphological traits, or attracting different pollinators to promote cross-pollination between flowers from different plants of the same species. This genetic exchange enhances biodiversity and plant health.

Explain the fertilization process

pollen grain lands on the stigma and germinates and the pollen tube of the male gametophyte grows down to the ovary.

Sperm enters the ovule through a pore called the micropyle.

What is double fertilization? What occurs?

In double fertilization, The pollen tube discharges 2 sperm into the female gametophyte w/in an ovule . one sperm fertilizes the egg to form a zygote, while the other sperm fuses with two polar nuclei to form the triploid endosperm, which nourishes the developing embryo.

Is the megasporangium the endosperm?

No, the megasporangium is not the endosperm; it is a structure within the ovule that produces megaspores, which develop into the female gametophyte. The endosperm, formed during double fertilization, serves as a nutrient source for the developing embryo.

What is the purpose of the endosperm?

The endosperm serves as a nutrient reservoir for the developing embryo, providing essential sustenance during early seed development.

Read

•Within a seed, the embryo consists of a root and one or two seed leaves called cotyledon

What are the 2 main groups of angiosperms?

The two main groups of angiosperms are monocots and dicots. Monocots have one cotyledon, while dicots have two.

True or False

there are more monocots than dicots

False

What are ways to differentiate monocots and dicots by the follwoing structures, cotyledon, leaf venation, roots, and flower petals

Monocots have one cotyledon, parallel leaf venation, fibrous root systems, and flower petals in multiples of three, while dicots have two cotyledons, net-like leaf venation, taproot systems, and flower petals in multiples of four or five.

Read

The Evolutionary Links Between Angiosperms and Animals

the Pollution and transport of seeds by animals are 2 important relationships in terrestrial ecosystems

What kind of plants do humans greatly rely on? Why?

Humans greatly rely on flowering plants, or angiosperms, for food, medicinal resources, and ecological services such as oxygen production and habitat provision. They play a crucial role in agriculture and sustain human diets.

What is artificial selection?

Artificial selection is the process by which humans breed plants and animals for specific traits, enhancing desirable characteristics over generations. It is a key method in agriculture and horticulture to improve crop yields and quality.