Biology 2 Lab Chapter 31

Angiosperm life cycle

-Eggs form within the embryo sac inside the ovules, which, in turn, are enclosed in the carpels. -The pollen grains, meanwhile, form within the sporangia of the anthers and are shed/ -Fertilization is a double process. -A sperm and an egg fuse to produce a zygote; at the same time, another sperm fuses with the polar nuclei to produce the endosperm. -The endosperm is the tissue, unique to angiosperms that nourishes the embryo and young plant.

Rafflesia can be up to

1 m across

Angiosperms range in size from

1 mm (wolffia to over 100 m tall (Eucalyptus)

There are more than ___________ living species of angiosperms

250,000

The stages of embryo development in the seed of Capsella (a eudicot) Globular stage

Cell division of the proembryo soon leads to the globular stage that is radially symmetrical and has little internal cellular organization.

The stages of embryo development in the seed of Capsella (a eudicot) Heart-shaped stage

Differential division of the globular stage produces bilateral symmetry and two cotyledons forming the heart-shaped embryo. The enlarging cotyledons store digested food from the endosperm. Tissue differentiation begins, and root and shoot meristems soon appear.

The stages of embryo development in the seed of Capsella (a eudicot) Proembryo stage

During development, the zygote divides to form a mass of cells called the embryo, initially the embryo consists of a basal cell, suspensor, and a two-celled proembryo. The suspensor is the column of cells that pushes the embryo into the endosperm. The endosperm is extensive but is being digested.

The sepal and petals are usually the most

conspicuous part of a flower, and a variety of flower types are distinguished by their sepal and petal characteristics.

The endosperm is depleted and food is stored in the

cotyledons

The stages of embryo development in the seed of Capsella (a eudicot) - The developing embryo grows, absorbs endosperm, and stores those nutrients in "seed leaves" called

cotyledons

Angiosperms are grouped into two groups depending on the number of

cotyledons (seed leaves) in the embryo

Megagametogenesis

develop into megagametophytes

Species having two cotydons were called

dicots

In snapdragons, one or more parts of at least one whorl are

different from other parts of the same whorl. These flowers are usually bilaterally symmetrical.

After the development of a microgametophyte (pollen grain) with sperm and megagametophyte (ovule) with an egg, sexual reproduction in angiosperms occurs: 3) One sperm nucleus fuses with the egg to form the diploid (2n) zygote, and the other sperm fuses with the two polar nuclei to form a triploid (3n) nucleus. This process is called ________ and is characteristic of angiosperms.

double fertilization

Biologists have long been interested in plant pollination, for

economic reasons

Most fruits are

either dry or fleshy

The entire haploid structure is called ______ ________ and consists of only six to ten nuclei, one of which is an egg.

embryo sac

The vast majority of species once classified as dicots are now known as

eudicots

Peduncle

flower stalk

After the development of a microgametophyte (pollen grain) with sperm and megagametophyte (ovule) with an egg, sexual reproduction in angiosperms occurs: 4) The zygote develops into the embryo. The triple fusion of the sperm nucleus and two polar nuclei forms the triploid endosperm that provides

food for the embryo

Tomatoes, beans, and okra are

fruit

Production of gametes by the gametophytes is called

gametogenesis

3. Each haploid spores develops into the __________ by mitosis and cellular differentiation.

gametophyte

Sometimes the dry wall surrounds the seed until it

germinates

The seeds of fleshy fruits remain in the tissue until

germination

2. The life cycle of flowering plants - the diploid sporophyte produces

haploid spores by meiosis

In monocots like lily flower parts usually occur

in multiples of three

ovules usually have two coverings called

integuments

Megasporogenesis

is the production of megaspores; it occurs in the sporangia of the flower ovary by meiosis of magaspore mother cells (megasporocytes).

Microsporogenesis

is the production of microspores within microsporangia of a flower's anthers via meiosis of microspore mother cells (microsporocytes)

The sporophyte of angiosperms is

large and heterosporous

Dry fruits crack or split at

maturity and release their seeds

megaspores undergo

megagametogenesis

Mature pollen grain are

microgametophytes

These microspores grow and mature into __________, which are also known as pollen grains.

microgametophytes

Flowering plants produce two types of spores:

microspores and megaspores

Species having one cotydon were called

monocots

A seven or eight-celled embryo sac is

most common

1. The life cycle of flowering plants involves the alternation of a multicellular haploid stage with a

multicellular diploid stage as is typical for all plants.

A mature fruit is

often larger than the ovary at the time of pollination and fertilization, which indicates that a great deal of development occurs while the seeds are maturing.

Genetic analyses revealed that species traditionally called dicots evolved from more than

one common ancestor

Angiosperms are important to humans because

our world economy is overwhelmingly based on them.

The megagametophyte and its surrounding tissues are called

ovule

Angiosperm reproduction depends on

pollination

5. The life cycle of flowering plants- The gametophyte within the flower is

reduced to a pollen grain (that contains a sperm nucleus) or an embryo sac (that produces an egg) within an ovule.

All monocots evolved from a common ancestor; as a result, their classification as monocots

remain unchanged

We eat and use vegetative structures (roots, stems, leaves) as well as

reproductive structures (flowers, fruits, seeds ) of angiosperms

The radicle has a

root apical meristem and root cap

A fruit contains

seeds

Within the pericarp as

seeds, various partitions, and placental tissues

Parts of a flower. This is a generalized flower with four primary parts:

sepals, petals, stamens and carpels

Vegetative adaptations of angiosperms and gymnosperms are

similar

In radially symmetrical flowers such as tulips, the different whorls of the flower consist of

similarly shaped parts that radiate from the center of the flower and are equidistant from each other.

A lily has

six stamens, three petals, three petal-like sepals, and three chambered ovary.

6. The life cycle of flowering plants - Production of spores in the sporophyte by meiosis is part of a larger process called

sporogenesis

The stages of embryo development in the seed of Capsella (a eudicot) Mature embryo - the mature embryo has large, bent cotyledons on each side of the

stem apical meristem

During pollination, pollen grains are transferred from the __________ where they germinate and grow a tube through the to the __________.

stigma; ovary. The tube nucleus controls the growth of the pollen tube, and the generative nucleus replicates to produce two sperm nuclei.

The fruit wall is usually tough and hard and is sometimes referred to as

stony

Dark brown to black pollen indicate

temperatures too high for oil deposits and suggests that a well will likely produce natural gas.

Microsporogenesis and Microgametogenesis occur in

the anthers of flowers

Examination of fossil pollen tells us about

the diversity of ancient flora and climatic change through the ages, and helps us locate ancient seas and their shorelines where pollen is known to accumulate.

Gynocium

the female portion of the plant that rises above and inside the androecium; consists of one or more carpels, each made up of an ovary, style, and stigma; the ovary contains ovules that contain the megagametophyte is called the embryo sac and contains female gametes.

4. The life cycle of flowering plants In angiosperms the sporophyte is

the large, mature organism with flowers that you easily recognize

Orange pollen suggests

the less intense heat associated with high-quality oil production

Sepals

the lowermost or outermost whorls of structures, which are usually leaflike and protect the developing flower; the sepals collectively constitute the calyx

Androecium

the male portion of the plant that rises above and inside the petals; consists of stamens each of which consists of a filament atop which is located anther; inside the anthers are pollen grains, which are the mocrogametophytes and contain the male gametes.

The structure of a fruit depends on

the number of carpels in each flower and whether or not the carpels are fused

Receptacle

the part of the flower stalk that bears the floral organs; located at the base of the flower; usually not large or noticeable.

The fruit often includes

the receptacle of the flower

The epicotyl is

the region between attachment of the cotyledons and the stem apical meristem; it has not elongated in the mature embryo.

The hypocotyl is

the region between the apical meristem and the radicle.

After the development of a microgametophyte (pollen grain) with sperm and megagametophyte (ovule) with an egg, sexual reproduction in angiosperms occurs: 5) The integuments of the ovule form

the seed coat, and the fruit develops from the ovary and other parts of the flower.

The microgametophyte (pollen) and megagametophyte (embryo sac) are completely dependent on

the sporophyte

After the development of a microgametophyte (pollen grain) with sperm and megagametophyte (ovule) with an egg, sexual reproduction in angiosperms occurs: 2) The pollen grain germinates, and a pollen tube grows through the stigma and style to the ovary. Its growth is governed by

the style and the tube nucleus of the pollen grain

Seeds range in size from

tiny ex a broomrape seed weighs only a few micrograms) to massive ex avocado seed can weigh more than 50 g.

The radicle, later to form the root, is differentiated

toward the suspensor

After the development of a microgametophyte (pollen grain) with sperm and megagametophyte (ovule) with an egg, sexual reproduction in angiosperms occurs: 1) pollination occurs when pollen is

transported to the surface of the flower's stigma

The haploid nuclei in a mature pollen grain include a __________ _____ (or vegetative nucleus) and a generative nucleus.

tube nucleus

Petals

whorls of structures located inside and usually above the sepals; may be large and pigmented (in insect-pollinated flowers) or inconspicuous (in wind-pollinated plants); the petals collectively constitute the corolla

Embryology of the mature zygote occurs

within the seed and before germination. This embryology and its controlling factors are complex, but various stages of development are easily observed.

the sepals collectively constitute the

calyx

Angiosperms include an infinite variety of flowers, ranging from the microscopic flowers of Lemna (duckweed) to the rare monstrous blossoms of

Rafflesia

The stages of embryo development in the seed of Capsella (a eudicot) Torpedo stage

The cotyledons and root axis soon elongate to produce an elongate torpedo-stage embryo. Procambial tissue appears and will later develop into vascular tissue.

A seed is

a mature ovule that includes a seed coat, a food supply, and an embryo.

A fruit is

a mature, ripened ovary plus any associated tissues.

A typical fruit has an outer wall called

a pericarp composed of an exocarp, mesocarp, and encarp

Pollen of some plants cause

allergies in some people