Roots, Shoots & Leaves

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1 Name Test Date Hour Plant Structure & Function #2 - Notebook Roots, Shoots & Leaves LEARNING TARGETS I can describe the functions of roots I can explain the nitrogen fixing process and why it is needed. I can describe the 2 basic types of root structure. I can describe the function of the stem. I can identify and explain the function of the petiole and the blade. I can describe the basic leaf structure and identify the purpose of each layer. I can explain the gas exchange and why it is needed. I can explain transpiration and why it is needed. I can explain how a plant moves water from its roots to its leaves without a heart to pump it. I can describe the basic structure of a plant cell and identify the purpose of each component. I can explain the process of photosynthesis. I can describe the components of photosynthesis and explain how the plant obtains them. I can explain the process of respiration and describe why it is needed. Scientific Language 1. Nitrogen Fixing Bacteria - A symbiotic partner providing useable nitrogen for plants and receiving food in return. 2. Axillary Bud- An embryonic shoot that gives rise to a new branch or flower. 3. Petiole- Part of the leaf that is like a small stem connecting the leaf to the rest of the plant. 4. Blade- Wide, flat part of the leaf. 5. Epidermis- The outer layer, or skin, of the blade. 6. Stoma- An opening, surrounded by two guard cells which control the opening and closing allowing carbon dioxide to enter the plant, and water and oxygen to leave the plant. 7. Gas Exchange- The process of allowing carbon dioxide to enter and oxygen to exit the plant. 8. Transpiration- The process of allowing water from the plant to evaporate into the atmosphere. 9. Mesophyll- The layers of cells found in the middle layer of the blade. 10. Palisade Layer- Aids in photosynthesis and has column shaped, tightly packed cells. 11. Spongy Layer- Irregular shaped cells creating air space which allows the gas exchange to happen and house the veins of the leaf. 12. Chlorophyll- The substance that allows a plant to use this light energy from the sun to turn carbon dioxide and water into a simple sugar. 13. Photosynthesis- The chemical process used to make food for the plant using the sun s energy, carbon dioxide and water. 14. Respiration- The chemical process used to unlock the energy in the glucose produced in photosynthesis.

2 Flowering Plants Flowering plants typically have three main parts:, and. Each of these structures has a specific or function to do for the plant. Let s work our way from the ground up. Roots Function Starting from the bottom, the root systems of most plants are as or than the above ground stems and leaves. Plants respond to in a process known as. This is responsible for the growth of roots due to its response or their growth gravity. Roots are an important part to plants. Roots act as an, preventing plants from being away by wind or away by moving water. The root system must also the other plant parts that are above ground the, and. The roots have tissue in which and dissolved substances move from the through to the and the. Root tissue also absorbs some of the it needs from the small spaces in the soil. This is why you don t want to over water and your plants. Roots can also store. When you eat or, you eat roots that contain food. Plants that grow from year to year use this stored food to begin their in the spring. Plants that grow in areas often have roots that store.

3 Nitrogen fixing One of the substances plants need the roots to absorb is, but most of nitrogen is found in our. Plants cannot use this form of nitrogen. Plants need to get the nitrogen they can use. It must first be converted or into a more usable form. The process of converting nitrogen is called. The energy from can change the form of nitrogen. There are also specialized whose function it is to nitrogen, converting it, so that it can be used by plants. After nitrogen is fixed, it can be by the roots and used by plants. The process of nitrogen being fixed, used by plants, and later returned to the atmosphere is referred to as the. Some plants (, ) have evolved to have a relationship with trapped in root nodules in the plant root. They trap nitrogen from air and it to a useable form. The plant can then use this as a nutrient for protein. The bacteria from gaining from the plant. Structure Not all roots are alike. Some plants have a root system where thin roots in many directions. Other plants have a large primary root called a. Taproots have roots growing from them and tiny root growing from the taproot and the secondary roots.

4 Shoots Moving up, the shoots system is everything above the. Stems are a part of the system of a plant. They range in from a few millimeters to hundreds of meters. They also vary in, depending on the plant type. Stems are usually ground, although the stems of some plants, such as the, also grow. Stems may be which are and, like those of. Other stems are hard, and in nature, like trees and shrubs. have woody stems. The stem of the plant connects the to the, helping to absorbed water and minerals through the to different parts of the plant. The stem also helps to transport the products of (i.e., sugars) from the leaves to the rest of the plant through the. Stems can also store for the plant. Another function of the stem is to provide to the plant, hold leaves, flowers, and buds. Stems may be, like that of a tree, or it may be branched, like that of a tree. At the of the stem and petiole you might find an. An axillary bud is an that gives rise to a new or. Leaves Continuing our plant journey, the grow from the stem. Leaves come in many sizes, shapes and colors. Most leaves have two main parts, the and the. The is the part of the leaf that is like a small stem the to the rest of the plant. Water and food through the petiole. The wide flat part of the leaf is its. The leaf blade is the of the plant where the making process,, usually occurs.

5 The structures of the stem and petiole continue into the. Once these structures enter the leaves they are called. Some leaves have veins that run ( ). Other leaves have veins which out in all directions from the center of the leaf ( ). Leaf Structure Epidermis The outermost layer of the blade is the, it s like. There is an and epidermis, on either side of the leaf. Gas Exchange The underside of the leaf contains, which are. Two cells surround each stoma, controlling its and. The stoma is responsible for allowing to enter the plant, and and to leave the plant. The process of allowing carbon dioxide to enter and oxygen to exit is called the.

6 Transpiration The process of the stoma allowing water from the plant to into the atmosphere is called. Water is evaporating from the surface of leaf cells to the air. When this happens new water is from the. Water has a property (they really each other) allowing water to be up through the as the old water evaporates. As water evaporates from the surface of the leaf, it the adjacent water molecules inside the, which tugs on the water molecules in the, which tugs the water molecules from the, which tugs water molecules into the roots from the. So water evaporating from the leaf the tug or pull of water through the stem. When new water is brought in, more are absorbed from the soil. This is how a plant material through its vessels without having a to pump it. The water in the plant also makes the cells more, which is why plants can stand tall without any. Transpiration also helps to the plants off, similar to. Plants have a or a waxy layer that covers the of all plant species. The cuticle helps to the rate of water from transpiration. Sun leaves have cuticles than shade leaves to transpiration. Guard cells control the of the so that the leaf does not lose too much water in, or conditions.

7 Mesophyll Below the epidermis there are layers of cells known as the, or. The middle leaf of most leaves typically contains two layers: the layer and layer. The palisade layer aids in and has -shaped, -packed cells. There may be one, two, or three of these cells. Below the palisade layer are -arranged cells of the layer. These cells have an shape creating between the cells. The air space found between the spongy layer cells allows the to happen. In the spongy layer, you will also find containing vascular tissue. Both layers of the mesophyll, middle leaf, contain many. The cells are the only cells to contain chloroplasts. Most of the food produced by plants is made in the cells of the layer.

8 Palisade Cells In addition to chloroplasts, plant cells have a cell, cell,, and. cell wall- provides structural for the cell and helps the cell. cell membrane - controls the of substances and of the cell. vacuole - stores the. nucleus - contains the and the cell s functions. Chloroplasts - the parts of a plant cell that contain the and produce the food through. cytoplasm - a like substance that the cell and supports the (parts of the cell). Photosynthesis No one packs a sack for a plant or a tree. Plants make their own through a process called. For photosynthesis, plants need the and. Photosynthesis only occurs in cells that contain, mostly those cells found in the layer of the leaf. However, all structures in plants, including soft and unripe, contain chloroplasts. Since are below ground and cannot absorb, their cells do not contain and are not.

9 The chloroplasts contain a special substance called, a green. A pigment is a substance that a particular part of the visible light spectrum and the rest. We see plants as, because the chlorophyll reflects light waves and absorbs the and light to use for photosynthesis. In the spring and summer most leaves have so much chlorophyll that it all other pigments contained in the leaves. In fall, the chlorophyll in some leaves and the leaf changes as other pigments become visible. Chlorophyll allows a plant to use this energy from the sun to turn ( ) and ( ) into a simple. The plant uses this sugar and minerals absorbed by the roots to create the it needs to live. During photosynthesis in addition to making sugar, a plant creates gas ( ) which it either uses for or releases it into the. Here is the equation for photosynthesis: Here is the equation for photosynthesis: C = O = H =

10 Carbon dioxide - 1 and 2 atoms Carbon dioxide enters the leaves through the on the underside of the leaf. The lower layer of the leaf with its loose-fitting cells let reach the other cells in the leaf. Water - 2 and 1 atom The water needed for photosynthesis is absorbed through the and transported through the to the leaf. Light ( ) A leaf usually has a surface area, so that it can a lot of light. In the upper part of the leaf where the light falls, the cells are adapted to absorb a of light. These tall boxed shaped cells have lots of. Glucose / Sugar / Carbohydrate - 6, 12 and 6 atoms The glucose made is used to help the plants. The extra glucose can be stored as. Stored starch can be turned back into later and used to release by. Starch and glucose can also be used by the plant to make for cell walls, for growth and repair, and and oils for storage. Oxygen - 2 atoms When plants combine carbon dioxide molecules and water molecules to make the there are twelve atoms left over. The spongy layer of the leaf lets the produced in photosynthesis leave the leaf easily as the plant. Plants do on to a small amount of the oxygen they produced in photosynthesis and use that oxygen to break down ( ) to give them in a process called.

11 Respiration To unlock the in the glucose produced in photosynthesis, green plants need to, just as animals do. Respiration takes place in the plant's cells, using to produce energy and giving off as a waste product. So in terms of the gas taken in and the gas given out, respiration is the of photosynthesis. During the when the plant is but not photosynthesising, is being taken in but not given out - and carbon dioxide is being given but not taken in. The word equation for respiration is the of the word equation for photosynthesis. Here is the word equation for respiration. Energy is put in brackets because it not a. glucose + oxygen carbon dioxide + water (+ energy) Luckily, plants use up more carbon dioxide in than they produce in, and produce more oxygen while photosynthesising than they use up while respiring - otherwise there would not be enough in the atmosphere for us animals to!

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