4th grade. Natural Science. Plants. BOM

We already know so many things about the fascinating world of   PLANTS!!!!

We know that plants are living things because they are born, grow, reproduce and die.

We know their parts too:

 

Also, we know that plants need some things to live such as water, minerals, carbon dioxide, light and energy from the Sun, and space. 

NUTRITION: PHOTOSYNTHESIS AND RESPIRATION

Plants are producers, they produce their own food, through a process called  PHOTOSYNTHESIS. 

Roots absorb water and minerals from the soil. This mixture is called the raw sap. The raw sap goes up the stem and into the leaves. The leaves absorb sunlight and carbon dioxide  through the stomata (little holes under the leaves) and transforms the raw sap into elaborated sap (glucose or sugar, which is the plant's food). The plant expells oxygen into the air.

PHOTOSYNTHESIS Vs RESPIRATION:

Unlike other living things, plants do not just consume oxygen, they produce it too. This happens during the day as part of photosynthesis. Plants actually produce more oxygen than they need and they expel this excess oxygen through the stomata.

At night, when photosynthesis stops, plants need to take in oxygen from the air. During this time they release carbon dioxide. This is respiration that happens at night and also during the day.

REPRODUCTION

But if flowers can't walk, how do they reproduce??? Sniff a flower with your nose and look what happens; you will get pollen all over your nose. Do you know why? You need to learn about POLLINATION.

Plants can be Flowering plants (plants with flowers) and Non-Flowering plants (Plants with no flowers)

Flowering plants can be
Angiosperm: plants with a fruit, with the seed inside.

Gymnosperm: plants with the seed inside a cone.

Flowering plants reproduce sexually, that means they need a male or female reproductive organs.

In this picture, we find the:

Male reproductive organs: Stamen= anther and filament

Female reproductive organs: Pistil= stigma, style, ovary and ovules.

POLLINATION: pollination occurs when pollen from the stamen lands on the stigma of a plant. Insects or the wind transport pollen that gets stuck in their body, from flower to flower.  

The pollen travels down the style into the ovary. The pollen then joins an ovule. Both make a seed. This process is called FERTILISATION.

NON-FLOWERING PLANTS reproduce ASEXUALLY: that means that spores are carried by the wind, as these spores land, they start to grow.










Some flowering plants have an asexual reproduction using a long horizontal stem called stolons. These stolons reach the ground and new roots grow and a new plant develops.

CLICK THIS LINK  and review some of the things we have learnt about flowers with this video! When you finish listening, try the test with the game! HAVE FUN!!!  :)