The chromosomes in
the nucleus of a cell contain information for inheritance of features from
parents to next generation in the form of DNA (Deoxyribo Nucleic Acid)
molecules. The DNA in the cell nucleus is the information source for making
proteins. If the information is changed, different proteins will be made.
Different proteins will eventually lead to altered body designs.
For unicellular
organisms, cell division, or fission, leads to the creation of new individuals.
Organisms such as Hydra
use regenerative cells for reproduction in the process of budding.
Roots, stems and
leaves of some plants develop into new plants through vegetative propagation.
In tissue culture,
new plants are grown by removing tissue or separating cells from the growing
tip of a plant.
The reproductive
parts of angiosperms are located in the flower. Stamens and carpels are the
reproductive parts of a flower which contain the germ-cells.
Stamen is the male
reproductive part and it produces pollen grains that are yellowish in colour. Carpel
is present in the centre of a flower and is the female reproductive part.
Reproduction in
flowering plants involves transfer of pollen grains from the anther to the
stigma which is referred to as pollination. This is followed by fertilisation.
The formation of
germ-cells or sperms takes place in the testes. The female germ-cells or eggs
are made in the ovaries.
The embryo gets
nutrition from the mother’s blood with the help of a special tissue called placenta.
Next Topic:-Science Class 10 NCERT Textbook- Lesson-9
Next Topic:-Science Class 10 NCERT Textbook- Lesson-9
