Reproduction in Plants

Reproduction in Flowering Plants


In this topic, we learn about the way plants reproduce, the various parts of flowers as well as the process of fertilization in the plant. This topic is very interesting:D

So basically, Sexual reproduction is the way plants allow offspring to inherit beneficial qualities from both parents, helping to increase the genetic variation within the population and the chances of the spieces's survival.

Let us look at the parts of the plant. Here is an example of a common flower:

A complete flower consists of the pedicel, receptacle, sepals, petals, stamens and carpels.
However, some flowers lack some of these parts and are known as incomplete flowers.

Functions of the parts of a Flower

Petal(Corolla)

-Bright Colored to attract pollinators(birds, insects etc.)
-May serve as landing platforms for pollinators.

Sepals(Calyx)

-Protects the parts of the flower when it is still in the bud stage.

Epicalyx

-Forms a layer outside the sepals.

Receptacle

-Enlarged end of stalk
-holds the other parts of the flower in place

Pedicel(stalk)

-attaches the flower to the plant

Reproductive Parts

Ovary
-Contains one or more ovules
Style
-connects stigma to ovary
-holds the stigma in optimal position for fertilisation
Stigma
-site for pollination
-secretes sugary fluids to stimulate growwth of pollen grain
Anther
-consists of 2 lobes, each containing 2 pollen sacs
-splits open to release matured pollen grains
Filament
-Holds the anther in position to release pollen grains.
-Contains pholem and xylem to provide nutrients and water for the development of the anther.

Pollination:

It is the transfer of pollen grains from the anther to the stigma. There are two different types of pollination: Self pollination and Cross pollination. During Self pollination, pollen grains are tranferred to the stigma of the same flower or a different flower on the same plant, whereas during Cross pollination, Pollen grains are transfered to the stigma of a different flower on a different plant of the same species.

The process of pollination and fertilisation:

-When the pollen settles on the stigma, the stigma sectretes a sugary fluid to stimulate growth of the pollen tube.
-The pollen tube extends in length as it grows towards the ovary, and upon entering the ovule in the ovary, the male gametes are released into it.
-The male gametes fuse with the female gametes.(double fertilisation)

Reflections:

I was very enthuastic while learning this topic! I have always enjoyed learning about Botany (Brings up some enjoyable memories in primary school)  and this was a great opportunity for me to do so! It was a bit tricky to memorize the plant parts and functions, as there were many of them, but I will try my utmost best. Cross pollination and self pollination were also a bit difficult to remember as we had to learn both the disadvantages and advantages, as well as a comparison between the two. I hope to be ready for the exam soon!






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