Flower Reproduction

The stamen and pistil.

What are the reproductive parts of a flower involved in genetic exchange?

They are modified leaves for protection and to attract pollinators.

What is the role of sepals and petals in flowers?

It involves the exchange of genetic material, specifically the sperm and egg, and occurs through the fertilization process where pollen grain reaches the stigma and goes to the ovary.

What is sexual reproduction in flowers?

filament and the anther.

What are the components of the stamen in a flower?

The anther releases pollen grains.

What does the anther do in the stamen?

Pollen grain lands on the stigma, then travels to the ovary where the fruit develops.

What is the general process of fertilization in flowers?

The pistil.

What is the female reproductive part of a flower called?

The stigma, style, and ovary.

What are the components of the pistil?

The placenta and the ovule.

What is contained within the ovary of a flower?

A cell inside the ovule that will undergo division to become the egg cell.

What is a megasporocyte?

Male gametophytes are sperm cells, while female gametophytes are egg and polar nuclei cells.

What is the difference between male and female gametophytes in plants?

It involves no exchange of genetic material and allows one individual to produce one or more individuals identical to itself.

What is asexual reproduction in plants?

A method of asexual reproduction.

What is the process of cutting a stem to create a new individual called?

Meiosis.

What type of cell division occurs in the development of gametophytes?

2n (diploid).

What is the chromosome number of microsporocytes?

n (haploid).

What is the chromosome number of pollen grains?

The gametophyte made up of 7 cells within the ovule.

What is the embryo sac?

They undergo meiosis to form microspores, which develop into pollen grains.

What happens to megasporocytes during reproduction?

It refers to a plant that contains specific cells essential for reproduction.

What is the significance of the term 'phyte' in botany?

Microsporangium.

What is the alternative term for pollen sac?

Meiosis occurs in two phases: meiosis I and meiosis II.

What is the process of cell division that leads to the formation of gametes in plants?

microsprocytes —> diploid.

What is the initial state of cells in the ovule before they become pollen grains?

Embryo sac.

What is the structure called that contains several cells within the ovule?

7 cells.

How many cells make up the gametophyte in the embryo sac?

Haploid (n).

What is the ploidy level of each cell in the embryo sac?

One cell becomes two haploid cells.

What is the result of Meiosis I in the formation of gametophytes?

The two cells from Meiosis I undergo division, resulting in four haploid cells.

What happens during Meiosis II?

Diploid (2n).

What is the ploidy level of megasporocytes?

The number of chromosomes in the mother cell divides into two, resulting in daughter cells with half the number of chromosomes.

What happens to the number of chromosomes during meiosis?

In the anther.

Where does male gametophyte formation occur?

Microsporocyte.

What is the original mother cell in male gametophyte formation?

Four haploid microspores.

How many haploid cells are produced from one microsporocyte?

A special covering, leading to the formation of pollen grains.

What is formed around the microspores as they develop?

Generative cell and tube cell.

What are the two types of cells present in a pollen grain?

One sperm fertilizes the egg, and another sperm fertilizes the polar nuclei.

What is double fertilization in plants?

A pollen grain with three cells: one tube cell and two sperm cells.

What is the final product of pollen grain formation?

They dissolve or sacrifice themselves to support the fertilization process.

What is the function of antipodal cells and synergids during fertilization?

Megasporocyte (diploid).

What is the initial cell type inside the embryo sac before meiosis?

One megasporocyte becomes four haploid megaspores.

What is the outcome of meiosis in the female gametophyte formation?

All cells have the same number of chromosomes except those in the pollen grain and inside the ovule.

What is the significance of the number of chromosomes in the pollen grain and ovule before cell division?

Pollination.

What is the process of transferring pollen to the female part of the flower called?

Three rounds of mitosis.

How many rounds of mitosis occur to produce the eight cells in the embryo sac?

They develop a thickened wall and become pollen grains.

What happens to the microspores after they are formed?

To facilitate the growth of the pollen tube for fertilization.

What is the role of the tube cell in the pollen grain?

They die out, leaving only one megaspore to develop.

What happens to the three megaspores during the development of the ovule?

It produces 8 cells.

How many cells does one megaspore produce after undergoing mitosis?

Antipodal cells, polar nuclei, and egg cell.

What are the three types of cells formed from the megaspore in the ovule?

They do not undergo complete cell division and have 2 nuclei.

What is unique about the polar nuclei in the ovule?

The transfer of pollen from the male anther to the female stigma.

What is the process of pollination?

The style recognizes it and aborts the process.

What happens if the wrong type of pollen grain passes the first checkpoint?

It is important for evolution and creates variable offspring, promoting diversity.

Why is sexual reproduction important in plants?

One sperm fertilizes the egg to form a zygote, and the other fertilizes the polar nuclei to form the endosperm.

What occurs during fertilization in plants?

The zygote is diploid (2n) and the endosperm is triploid (3n).

What are the ploidy levels of the zygote and endosperm?

The stigma secretes juices to soften the pollen grain wall if the pollen grain is compatible.

What is the role of the stigma during pollination?

embryo.

What does the zygote develop into after fertilization?

The endosperm tissue within the ovule.

What does the endosperm cell develop into?

The ovule becomes the seed.

What becomes of the ovule after fertilization?

The ovary develops into the fruit.

What does the ovary develop into after fertilization?

The ovary wall that becomes the outer layer of the fruit.

What is the pericarp?

It is the opening that allows for the entry of pollen and later becomes part of the seed.

What is the function of the micropyle in the seed?

The anther develops earlier than the pistil.

What is one plant strategy to prevent self-fertilization?

Outbreeding increases genetic diversity, which is beneficial for adaptation and survival.

What is the significance of outbreeding in plants?

It becomes the placenta of the fruit.

What happens to the placenta of the ovary after fertilization?

The pollen tube elongates and pushes the sperm cells down the style.

What is the relationship between the pollen tube and the sperm cells?

It delivers the sperm cells to the egg cell and polar nuclei.

What is the role of the pollen grain during fertilization?

It leads to the formation of seeds and fruits.

What is the outcome of successful fertilization in plants?