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Spermicides are the pills used for killing sperms.

B) Daughter organism dies.

a) Parthenogenesis is a process of reproduction where there is a shift from sexual to asexual mode of reproduction. 

b) In this process generally the female garnets develops into zygote without fertilization. 

c) This strange kind of reproduction occur in bees, ants and wasps. 

d) The parthenocarpic zygote develop into male (Monoploid) while the fertilized one developed into female (Diploid)

This process occurs by the development of female gamete or ovum directly develops into zygote without fertilisation.

Cutting: A vegetative propagation method in which a piece of stem or root of the source plant is placed in suitable soil to get a new plant.

Parthenogenesis: It is the process of development of an organism from an unfertilized egg. eg: Drones (Male honey bees).

Progeny: A genetic descendant or offspring; The young of 1mai and plants.

Cyst: A small capsule-like sac that encloses certain organisms in their dormant or larval stage.

(C) Androecium

Flowers having both the stamen and carpel are called bisexual flowers.

Eg: Datura.

The three parts of carpel or gynoecium are ovary, style and stigma.

1. In 1852 a German scientist, Robert Remak published his observations on cell division and stated that the binary fission of cells was the means of reproduction of animal cells. 

2. This view was widely publicized by Rudolf Virchow who gave the phrase “Omnis cellulade cellula” means all cells arising from pre existing cells. 

3. In 1879 Walther Flemming reported that there were string like structures in the nucleus which split longitudinally during cell division. He named the process as mitosis means fine threads as the dividing structures resembled threads.

4. Wilhelm Roux proposed that each chromosome carried a different set of heritable elements and suggested that the longitudinal splitting observed by Flemming ensured the equal division of these elements. 

5. Combined with the rediscovery of Gregor Mendel’s 1866 paper on heritable elements in peas, these results highlighted the central role of the chromosomes in carrying heritable material or genetic material. 

6. The scheme of mitotic division was confirmed in 1904 by Theodor Boveri. 

7. The chemical nature of the genetic material was determined in a series of experiments over the next fifty years. 

8. The structure of DNA – the constituent of the genetic material was determined in 1953 by James Watson and Francis Crick.

1.  Corian and Amnion are the membranes formed by the growing embryo.
2. The umbilical cord connects the embryo with the placenta.
3. The gestation period in human beings is 9 months or 280 days.
4. The reproductive part of the flower that contains sex cells or germ cells is stamens and carpels.
5. Pollen grains are spores produced by pollen mother cells present in the pollen sac of the anther.
6. Pollen grain germinates on stigma and produces a slender thin-walled pollen tube, one of its two nuclei divides and forms two sperms.
7. Union of one sperm with the egg in embryosac is called fertilization.
8. Union of second sperm with fusion nucleus is known as double fertilisation.
9. Continuation of life starts from cells either those of the general body or the sex cells.

1. The growing embryo form two membranes – Chorion and Amnion. 

2. Chorion establishes connection with the walls of the uterus and helps in the supply of nutrients to the embryo and in the removal of wastes from the embryo. 

3. Amnion forms a sac like structure around the embryo and amniotic fluid is present between layers of Amnion.

4. Amnion and Amniotic fluid give protection to the embryo against mechanical shocks. 

5. Placenta is a tissue formed around 12 weeks of pregnancy by the cells from the embryo and mother.

6. Embryo receives all the required nutrients and oxygen for its metabolism from the mother through the blood vessels present in the placenta. 

7. Another membrane called allantois, which originates from the digestive canal of the embryo forms the major part of a tube like structure called umbilical cord. 

8. Umbilical cord contains very important blood vessels that connect the embryo with the placenta.

Meiosis: Cell division which occurs in germ cells or reproductive cells forming four daughter cells (gametes) having half of the number of chromosomes when compared to their parental cell.

Meiosis has two phases, during the first phase the parent cell divides twice.

The second phase of meiosis is similar to normal mitosis.

1. Where does meiosis occur in? 

2. How many daughter cells are produced at the end of meiosis? 

3. In which phase of meiosis karyokinesis takes place? 

4. Name the scientist who discovered meiosis for the first time.

Foeticlde: It is the act of causing the death of a foetus by destruction or aborting.

Chromosome: A thread-like structure of nucleic acid (RNA, DNA) and proteins found in cells, carrying genetic information In the form of genes.

If the progeny have thousands of chromosomes in them, it results in formation of abnormalities in each generation.

1. Daughter cells formed in meiosis are gametes. 

2. These gametes have half of the chromosomes in number as the parent, 

3. If the gametes do not have half of the chromosomes in number as the parent, when they fuse, they form zygote with double the number of chromosomes when compared to parent cell. 

4. If it continues, cells in the offspring will have thousands of chromosomes within few generations. 

5. If the chromosome number increases in a species it leads to the formation of abnormalities.

(B) Sexual reproduction

A) to create healthy society

(C) Anaphase

(B) Metaphase

(A) Prophase

Prophase, Metaphase, Anaphase and Telophase are the different stages in mitosis.

Answer is (C) 1, 2, 3

Interphase can be divided into three phases. They are the G₁ phase, S phase and G₂ phase.

S phase is the period of DNA synthesis leading to duplication of chromosomes.