14.4 Seed Plants: Angiosperms

• Because it is similar to amphetamines, its use is restricted to prescription drugs.
• Unlike other gymnosperms, all gnetophytes have vessel elements in their xylem.

• The angiosperms, or flowering plants, have successfully evolved to dominate most of the land.
• The division is second only to insects in terms of diversity, with more than 260,000 species.

• There are flowers in a garden.
• Plants are abundant in the landscape.
• The colors of flowers are adapted to pollination by insects and birds.
• Plants were able to form evolutionary relationships with animals and insects through flowers.
• Fruit protects the embryo and is an agent of dispersal.
• The dispersal strategies that help with the spread of seeds are reflected in different structures on fruit.

• The flowers are organized around a central stalk.
• All flowers have the same structures, and they vary greatly in appearance.
• There are some exceptions to the fact that Sepals are usually photosynthetic organs.
• The word tepal is derived from the fact that the corolla in lilies and tulips looks almost identical.
• Small and dull flowers are pollinated by wind.
• There are sexual organs at the center of the flower.

• A flower may contain more than one carpel.
• The female gametophytes are protected by the thick tissues of the carpel.
• Each ovule in the ovary develops into a seed after fertilization.
• The anther is supported by the filament.

• This image shows the structure of a flower.
• Both male and female floral organs are carried by perfect flowers.

• As the seeds grow, the seed enlarges in size.
• The walls of the ovary form the fruit as the seed develops.
• A fruit is a fully grown ovary that has been fertilized.
• Vegetables are actually fruit.
• The thick ovary tissue of bell peppers and string beans is what makes them technically fruit.
• The scientific name is a samara and it is also fruit.

• The mature fruit can be described as dry.
• Fruit with flesh include the familiar berries, peaches, apples, grapes, and tomatoes.
• Some examples of dry fruit are rice, wheat, and nuts.
• Not all fruits are derived from the ovary.

• Some fruits are derived from different parts of a flower.
• Some fruits, like watermelon and orange, have rinds.
• Fruits are an agent of dispersal regardless of how they are formed.
• The dispersal mode is reflected in the variety of shapes and characteristics.
• The wind carries the fruits of trees and dandelions.
• Coconuts are moving.
• Fruits that are colored, perfumed, and sweet are attractive to herbivores, which eat the fruit and scatter the tough undigested seeds in their feces.
• Other fruits have hooks that can be used to hitch rides on animals.

• The main phase of an angiosperm's life cycle is the adult.
• Gymnosperms are Heterosporous.
• The male and female gametophytes form an ovule containing the male and female gametophytes.
• Inside the anthers' microsporangia, male microsporocytes divide by meiosis and give rise to haploid microspores that give rise to pollen grains.
• There are two cells in a pollen grain, one of which will become a sperm and the other of which will become a pollen tube cell.

• The diagram shows the lifecycle of a plant.
• The embryo sac and the pollen grain are the actual gametophytes.
• The process of double fertilization is unique to angiosperms.

• The female gametophyte is produced when four haploid megaspores are produced.
• One of these is larger than the others and undergoes a procedure to form an embryo sac.

• There are eight nuclei in seven cells.
• The embryo sac has an egg and two cells at one end and three cells at the other.

• A pollen tube extends from the grain, grows down the style, and enters through an opening in the ovule when it reaches the stigma.
• The embryo sac contains sperm cells.

• A double fertilization event is unique to angiosperms.
• The sperm and egg combine to form a diploid embryo.
• The diploid nucleus in the center of the embryo sac is where the other sperm form a triploid cell that develops into the endosperm: a tissue that serves as a food reserve.
• The cotyledons act as conduits to transmit the broken-down food reserves to the developing embryo.
• The embryo is protected by a layer of integuments forming the coat, the endosperm with food reserves and the well-protected embryo.

• Double fertilization can only happen in angiosperms.

• Most flowers have both carpels and stamens.
• Both types of sex organs can be found in these flowers.
• Self-pollination can increase the number of genetic defects in offspring.

• A plant may have both genders in each flower, or it may have imperfect flowers of both kinds on one plant.
• Plants with perfect flowers are referred to as hermaphroditic.
• Some plants are dioecious, meaning "two houses," and have male and female flowers on different plants.
• Cross-pollination occurs all the time in these species.

• Plants with both male and female reproductive structures are monoecious.
• The reproductive structures of males and females are different in dioecious plants.

• Modern angiosperms appear to be a monophyletic group.

• They are grouped together in a group called the Magnoliidae.
• magnolia trees, laurels, water lilies, and the pepper family are part of the Magnoliidae group.

• The magnolias are considered archaic because of their large, fragrant flowers with many parts.
• There are fragrant leaves and flowers in the trees.
• The Laurales are small trees and shrubs that grow in warmer climates.
• The water lilies, lotus, and similar plants are part of the nymphaeales.
• The leaves of the Nymphaeales float on the water surface or grow underwater.
• Water lilies have graced ponds and pools since antiquity.
• A group of herbs, shrubs, and small trees grow in tropical climates.
• They have small flowers without petals that are arranged in long spikes.

• The flowers are small.
• The magnolia tree's red berries, which are characteristic of the final stage, are just starting to appear.

• Plants in the monocot group have a single cotyledon in the seedling, as well as other features.
• The flower parts are arranged in a three- or six-fold symmetry.
• Monosulcate was the type of pollen from the first angiosperms.
• The feature is still present in the modern monocots.
• The stem's vascular tissue is not arranged in a particular pattern, and true woody tissue is rarely found in monocots.
• The root system is mostly adventitious.
• The true lilies, orchids, grasses, and palms are some of the familiar plants in the monocots.

• The world's major crops are flowering plants.
• One staple food is rice, as are other cereals and beans.
• Some flowers, such as the (c) lily, are monocots, while others, such as the (d) daisy, are eudicots.

• Eudicots are characterized by the presence of two cotyledons.
• There are veins in the leaves.
• There are four, five, or many whorls of flower parts.
• There is a ring in the stem.
• The pollen that is trisulcate or triporate is produced by most eudicots.
• The root system is usually anchored by a single root.
• Two-thirds of flowering plants are Eudicots.

• It was possible to colonize land and survive out of water with the help of land plants.
• The adaptions to life on land include tissues, roots, leaves, and a tough outer layer.
• Land plants include nonvascular plants.
• Plants with seeds have apical meristems, while seedless plants have embryo stores.
• The haploid plant called a gametophyte and the diploid plant called a sporophyte are two of the characteristics of all land plants.

• Nonvascular plants are small.
• The gametophyte is the most important stage of the life cycle.
• They don't have a vascular system or roots to absorb water and nutrients.
• The three main groups are the liverworts, hornworts and mosses.
• They are called bryophytes.

• The book is available for free at http://cnx.org/content/col11487/1.9 There were leaves and roots to absorb water from the ground.
• Club mosses are the most primitive of the seedless plants.

• Gymnosperms are Heterosporous seed plants that produce naked seeds.
• They were the dominant plant life during the Mesozoic era and appeared in the Carboniferous period.

• Gymnosperms are in four divisions.
• The conifers are the main plants at high altitudes and latitudes.
• Cycads grow in tropical climates.
• The Gnetophytes are a diverse group of species that produce vessel elements in their wood.

• 90 percent of all plant species are angiosperms, the dominant form of plant life.
• A lot of crop and ornamental plants are angiosperms.
• Plants are derived from modified leaves.
• The reproductive parts of a flower are protected by the stamens and the carpels.
• The male gametes are pollen grains.
• The female gametes are inside the carpels.
• The ripening of the walls of the ovary can facilitate seed dispersal.

• The life cycles of angiosperms are dominated by the sporophyte stage.
• A unique event to angiosperms is double fertilization.

• According to the number of cotyledons in the seedlings, the flowering plants are divided into two main groups.
• Basal angiosperms are older than monocots.

• A flower without a megasporangium is not a flower.

• They grow better in cold weather.

• They do not need water.

• The haploid stage leads to the d.

• Plants carry seeds on their leaves.

• There are reproductive structures in a flower.

• A single cycle develops corn.