Page 192 - Innovator's Science-8

You might wonder: if both parents pass on their genetic material, wouldn’t
the new organism end up with double the information? This doesn’t

happen because each parent produces special reproductive cells, called
gametes, that carry only half the genetic material.
• Male gametes (like sperm or pollen)

• Female gametes (like eggs or ovules)

When the male and female gametes unite, they form a zygote with a
complete set of genetic instructions— half from each parent.

This mix of genetic material explains why babies don’t look exactly like
either parent. Each child gets a unique combination of traits like eye colour,
hair type, and height. Even siblings can look different depending on how

the genes combine.
Sexual Reproduction in Plants: In flowering plants, reproduction happens
through specific parts of the flower:

• Pollen grains , found in the anther, are the male gametes.

• Ovules , located deep within the flower, are the female gametes.
Pollination is the process where pollen is carried from one

flower. to another, often by wind, insects, or animals. When the
Anther
male and female gametes meet, fertilisation occurs, forming a
zygote that develops into a seed. The ovule becomes the seed,

Ovule and the surrounding flower parts grow into a fruit.

Steam Animals and birds often help in spreading seeds by eating fruits
A flower and dropping seeds far away. For example, a bird might eat a
banyan fruit and later excrete the seed, which may sprout in a wall crack

after rain.

Once a seed gets water and the right conditions, it begins to grow first with
roots, then shoots, and finally new leaves.
Sexual Reproduction in Animals: In animals, male and female gametes are

called sperm and eggs . The process of fertilisation happens when these
two gametes combine to form a zygote.

There are two main ways this happens:
• In aquatic animals like fish and frogs, the
sperm and eggs are released into water,

where fertilisation takes place outside
the body. The zygote then grows into an
embryo in the water.
Formation of zygote

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