Journey of a Water Drop

1. Journey of a Water Drop By Aqeelah Welsh

2. The water cycle The water from rivers, the ocean and lakes is evaporated from a liquid to a gas. The water vapour cools down and condenses forming clouds. When water molecules and clouds collect into big enough drops they fall causing rain. The rain soaks up in the soil.

3. The roots • The root systems anchors the plant and collects water and nutrients from the soil. • Root hairs are attached to the roots. The root hairs absorb the water and the dissolved nutrients that the water contains. • Inside the roots are two tissues, Phloem and Xylem. Xylem is a tissue in the plant that conducts water and minerals from the roots and up through the plant. Phloem is a tissue that conducts products of photosynthesis throughout the plant including the roots.

4. The Stem • Stems are the part of a plant that bear leaves and flowers, and they are the continuation of the vascular system pipeline that starts in the roots. • After the roots, the water is carried up the stem by the xylem and phloem tissues. It is then distributed to different parts of the plant. • The Pith is also in the center of the stem. In some plants the Pith breaks down forming a hollow stem and in other plants it is filled with xylem wood fiber.

5. The leaf • The leaf has opening called stomata that allows carbon dioxide to get in. The water (that has travelled up) and the carbon dioxide spread through the leaves. They spread into cells called palisade and spongy cells. • The cells contain structures called chloroplasts, which are filled with the green pigment chlorophyll. In photosynthesis chlorophyll traps energy from the sun and stores it as chemical energy. This process splits water molecules into hydrogen and oxygen atoms. The chemical energy is used to create glucose from the hydrogen and carbon dioxide. The glucose then dissolves into extra water molecules and gives the plant plenty of food for growth. The oxygen is released from the leaves. This is the photosynthesis cycle. • The plants take the carbon dioxide that we release and they release oxygen for use. So it is basically like a cycle. • The outer layer of tissues is called an epidermis. The wax cuticles are a protective outer layer of epidermis that prevents water loss.

7. Bibliography • http://www.reec.nsw.edu.au/k6/page/wa32.htm • http://leavingbio.net/flowering%20plants.htm • http://www.cmg.colostate.edu/gardennotes/133.html • http://www.brainpop.com/science/cellularlifeandgenetics/photosynthesis/ • http://www.brainpop.com/science/earthsystem/watercycle/