Embryo Sac (Female Gametophyte)
Covers the development of the female gametophyte from a functional megaspore and its mature 7-celled, 8-nucleate structure.
What is Embryo Sac (Female Gametophyte)?
The female gametophyte in angiosperms, typically an 8-nucleate, 7-celled structure developed within the ovule.
Key points
- Understand the origin and development of the embryo sac.
- Identify the different types of cells and nuclei within the embryo sac.
- Differentiate between the number of nuclei and cells.
- Explain the significance of the embryo sac in plant reproduction.
Common exam trap
Confusing the number of nuclei and cells in the mature embryo sac.
Definitions
- Term
Embryo Sac
- Meaning
The female gametophyte in angiosperms, typically an 8-nucleate, 7-celled structure developed within the ovule.
- Term
Megasporogenesis
- Meaning
The process of formation of megaspores from a megaspore mother cell through meiosis.
- Term
Monosporic Development
- Meaning
Development of the embryo sac from a single megaspore.
- Term
Egg Apparatus
- Meaning
The group of three cells at the micropylar end of the embryo sac, consisting of one egg cell and two synergids.
- Term
Synergids
- Meaning
Two cells flanking the egg cell in the embryo sac, which play a role in pollen tube guidance.
- Term
Antipodal Cells
- Meaning
Three cells located at the chalazal end of the embryo sac.
- Term
Secondary Nucleus
- Meaning
The diploid nucleus formed by the fusion of two haploid polar nuclei in the central cell of the embryo sac.
Learning objectives
Understand the origin and development of the embryo sac.
Identify the different types of cells and nuclei within the embryo sac.
Differentiate between the number of nuclei and cells.
Explain the significance of the embryo sac in plant reproduction.
Prerequisites
Meiosis
Mitosis
Structure of the ovule
Gametogenesis
Common mistakes
Confusing the number of nuclei and cells in the mature embryo sac.
Forgetting that the secondary nucleus is diploid, not haploid.
Assuming all four megaspores are functional.
Keywords
Embryo Sac
Female Gametophyte
Megaspore
Monosporic Development
Ovule
Egg Apparatus
Synergids
Antipodal Cells
Secondary Nucleus
Angiosperms
Practice preview
Where is the female gametophyte (embryo sac) located within an angiosperm flower?…
easy
The development of the embryo sac from a single functional megaspore is known as:…
easy
How many cells and nuclei are typically present in a mature female gametophyte (embryo sac) of angiosperms?…
easy