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(i) Agave primarily propagates through offsets or "pups." These are small plantlets that grow around the base of the mature Agave plant. They can be separated and replanted to grow into new individual plants.

(ii) Bryophyllum, also known as the mother of thousands or mother of millions, reproduces vegetatively through tiny plantlets that develop along the margins of its leaves. These plantlets, once detached from the parent plant, can take root and grow into new individuals.

The tassels of a corn cob represent the male reproductive structure of the corn plant, which is analogous to the stamen in a flower. Specifically, the tassel contains the pollen-producing organs called anthers, which release pollen grains.

As an AI text-based model, I'm unable to directly draw diagrams. However, I can describe the cellular components of a mature microspore of an angiosperm for you:

1. Cell Wall: The outermost layer providing structural support.
2. Plasma Membrane: Surrounds the cytoplasm, controlling the movement of substances in and out of the cell.
3. Cytoplasm: Gel-like substance where organelles are suspended.
4. Nucleus: Contains genetic material (DNA) and controls cellular activities.
5. Mitochondria: Organelles responsible for energy production through cellular respiration.
6. Endoplasmic Reticulum (ER): Involved in protein synthesis and lipid metabolism.
7. Ribosomes: Synthesize proteins.
8. Golgi Apparatus: Modifies, sorts, and packages proteins and lipids for secretion or transport.
9. Vacuole: Membrane-bound organelle responsible for storage of various substances.
10. Microtubules and Microfilaments: Part of the cytoskeleton, providing structural support and facilitating cellular movements.
11. Pollen Grain: The mature microspore itself, containing the male gametophyte of the plant.

This description provides an overview of the cellular components you would find in a mature microspore of an angiosperm.

The filiform apparatus is a structure found in the mature embryo sac of angiosperms (flowering plants). Its primary function is to guide the pollen tube towards the embryo sac during fertilization. The filiform apparatus consists of several elongated cells with highly specialized wall structures located near the micropylar end of the embryo sac. These cells produce chemicals that attract and guide the pollen tube, facilitating the successful fertilization of the ovule.

The human oviduct, also known as the fallopian tube, is divided into several parts through which the ovum (egg) travels until it meets the sperm for fertilization. These parts include:

1. Infundibulum: The funnel-shaped opening of the fallopian tube located near the ovary. It has finger-like projections called fimbriae that help capture the released egg during ovulation.

2. Ampulla: The widest and longest part of the fallopian tube, located between the infundibulum and the isthmus. It is the usual site for fertilization to occur.

3. Isthmus: The narrowest part of the fallopian tube, adjacent to the uterus.

4. Interstitial (intramural) part: The segment of the fallopian tube that penetrates the uterine wall.

After ovulation, the egg is released from the ovary and captured by the fimbriae of the infundibulum. It then travels through the fallopian tube propelled by ciliary movement and muscular contractions until it reaches the ampulla where fertilization typically occurs. If fertilization occurs, the resulting zygote then travels down the fallopian tube towards the uterus for implantation.

In the human female reproductive system, fimbriae are finger-like projections found at the end of the fallopian tubes, which are also known as uterine tubes or oviducts. The fimbriae are located near the ovaries, extending from the infundibulum of the fallopian tube. Their primary function is to help capture and guide the released egg (oocyte) from the ovary into the fallopian tube.

When an egg is released from one of the ovaries during ovulation, the fimbriae create a sweeping motion to gently coax the egg into the fallopian tube. From there, the egg is transported towards the uterus, where it may be fertilized by sperm if  intercourse has occurred. If fertilization does occur, the resulting embryo will travel down the fallopian tube and implant itself into the lining of the uterus for further development. If fertilization does not occur, the egg is eventually expelled from the body during menstruation.

Sure, here are one positive and one negative application of amniocentesis:

Positive Application:

1. Prenatal Diagnosis of Genetic Disorders: Amniocentesis allows for the detection of genetic disorders such as Down syndrome, cystic fibrosis, and spina bifida in the fetus. This information enables parents to make informed decisions about the pregnancy, including early preparation for caring for a child with special needs, exploring treatment options, or even considering termination if they so choose.

Negative Application: 2. Risk of Complications: Amniocentesis carries a small risk of complications, including miscarriage. Although the risk is relatively low (estimated to be around 0.5-1% according to some studies), it is still a concern for expecting parents. Additionally, there is a slight risk of infection, leakage of amniotic fluid, and injury to the fetus. These potential complications weigh on the decision-making process for many parents considering whether or not to undergo the procedure.

Sure, here's one positive and one negative application of amniocentesis:

Positive Application: Prenatal Diagnosis Amniocentesis allows healthcare providers to diagnose certain genetic disorders and chromosomal abnormalities in a fetus during pregnancy. This can provide parents with valuable information about the health of their baby and help them make informed decisions about their pregnancy and future medical care. Early detection of conditions like Down syndrome, cystic fibrosis, and neural tube defects through amniocentesis can enable parents to prepare emotionally, seek appropriate medical care, and make decisions regarding pregnancy management.

Negative Application: Risk of Complications One of the main drawbacks of amniocentesis is the risk of complications, albeit low. There's a small risk of miscarriage associated with the procedure, estimated to be around 0.3-0.6%. Other potential complications include leakage of amniotic fluid, infection, and injury to the fetus. While these risks are relatively rare, they are still important considerations for pregnant individuals and their healthcare providers when deciding whether to undergo amniocentesis.

Copper-T (Cu-T) is a type of intrauterine device (IUD) used as a contraceptive method for human females. It is a small, T-shaped device that is inserted into the uterus by a healthcare provider.

The primary mechanism of action of Cu-T as a contraceptive is its effect on sperm viability and motility, as well as its impact on the uterine environment, making it less conducive to fertilization and implantation. Here's how it works:

1. Copper ions: The Cu-T device is made of plastic and wrapped in copper wire. Copper ions are released continuously into the uterine cavity. These copper ions have spermicidal effects, impairing the sperm's ability to move (motility) and reducing its viability, thereby preventing fertilization.

2. Inflammatory response: The presence of copper in the uterine cavity also triggers an inflammatory response. This response creates an environment that is hostile to sperm, making it difficult for them to survive in the uterus and travel to the fallopian tubes to fertilize an egg.

3. Thickening of cervical mucus: Copper ions released by the Cu-T device can also alter the consistency of cervical mucus, making it thicker and more difficult for sperm to penetrate and reach the uterus.

4. Preventing implantation: In some cases, if fertilization does occur despite the above mechanisms, the presence of the Cu-T device in the uterus can interfere with the implantation of the fertilized egg into the uterine lining, thereby preventing pregnancy.

Overall, Cu-T acts as an effective contraceptive by employing multiple mechanisms to prevent sperm from reaching and fertilizing an egg, as well as creating an environment within the uterus that is inhospitable to both sperm survival and embryo implantation.