Plants Respond To Gravity

Phototropism is the growth of a plant in the direction of its light source. Phototropism occurs due to a hormone called auxin which is produced at shoot tips. Auxin influences cell division, if there is light on one side then the dark side will receive more auxin and therefore more cell division will occur on that side, which will force the plant to bend towards the light therefore affecting the height of the

Plants are a living organism of the kind exemplified by trees, shrubs, herbs, grasses, ferns, and mosses, absorbing water and inorganics substances through its roots, and synthesizing nutrients in its leaves by photosynthesis using the green pigment chlorophyll (Oxford Dictionaries, 2015). Plants are the backbone of all life on Earth and an essential resource for human well-being (BGCI, 2015). For all forms of life, plants form the basic food staples. They are the major source of oxygen and food on earth since no animal is able to supply the components necessary without plants (Jennifer C, 2014). Plants make food – they are the only organisms that can convert light energy from the sun into food. Plants make oxygen – one of the materials that plants produce as they make food is oxygen gas for animals and people to stay alive. Plants provide habitats for animals – it is a primary habitat for thousands of other organisms. Plants help make and preserve soil – the roots of plants help hold soil together which help reduce erosion and helps conserve the soil. Plants provide useful products for people – many plants are important sources of product that people use, including food, fibres

Plant cells have selectively permeable membrane that allows selective substances to penetrate into the cell. Cell membranes are consisting of lipid layer that are made up of phospholipids. (Essays, UK.2013). These phospholipids are amphipathic in nature, which have phospholipids head and tail respectively. Phospholipids heads are hydrophilic and tails

One of the ways that plants demonstrate the characteristics of living organisms is tropism. Tropism is defined as movement or growth response of an

Subpoint- Helps to level out the uric acid levels and to increase glutathione, and helps with the oxidate stress.

A plant can control its turgor pressure through its central vacuole and cell wall. If a great amount of water is inside the cell, the central vacuole will take in some of the water to take some of the pressure of the cell wall. The cell wall can also eliminate water from making its way into the cell. The would cause the cell to keep expanding, but slowly eliminate its excess

Despite its importance osmosis may also damage cells by causing them to; a) shrink from water loss or b) burst from too much water gain. Plant cells [fig 3] have adapted themselves to ensure that these factors do not affect them, by forming a ridged wall, known as the cell wall, around their cells. The cell wall maintains the shape of the cell, and prevents the cell from bursting in a hypotonic medium by resisting water pressure. Plant cells have also adapted a larger vacuole, which occupies 80% or more of the cells cytoplasm (Davidson, 2004); allowing plants to store more water and nutrients per cell. Vacuoles also play a structural role in plant cells; by swelling when liquids contact them, plant vacuoles are able to control turgor pressure within the cell. This helps maintain the structural integrity of the cell as well as providing the plant with suitable amounts of water and nutrients; however the cell will never burst because the vacuole is contained within the cell wall. If plant cells are deprived of water their vacuole will begin to shrink, yet due to the cell the wall, the plant cell will be able to maintain its shape. [fig.4] Animal cells [fig 5] on the other hand do not have this

(Click Slide) Due to adhesion, capillary action occurs in plants. Water absorbed from the roots sticks to the walls of xylem vessels in plants, and cause an upward motion. Sometimes, you may see that when you wet a paper towel, the water quick travels up the towel. Capillary action occurs when adhesive forces are stronger than cohesive forces.

This is made possible by the support lent to it by the slightly elastic cellulose cell wall. It will support a turgid cell enough to prevent it from bursting (see left). It is turgid cells such as this that provide a plant with its support. Animal cells on the other hand, do not have supporting cell walls, just cell membranes. As plants are always surrounded by water, it is vital for them to have cell walls, but animal cells, surrounded by blood (low water concentration), do not need as much support.

and other substances that are reabsorbed back into the body. It is also responsible for

The tobacco plant like many plants contain a cell callus. A cell callus contains somatic undifferentiated cells and can be used to differentiate into specialized tissues of the tobacco plant, or any plant used, by being induced with the addition of different types of hormones, such as cytokinin and auxin. Cytokinin and auxin are mostly used in plant tissue culture simultaneously to provoke the formation of a plantlet or callus. There is a common use of Kinetin in plant tissue culture since when added it will promote cell division to initiate shoot tissues from calluses of the plant. Kinetin is a type of cytokinin hormone. In regards to auxin related hormones, Indole-3-acetic acid (IAA) is also commonly used since it promotes the initiation of roots for the root tissue of the plant. In this

Plant cells react differently to osmosis than animal cells. When an animal cell is placed in a hypertonic solution, water will leave the cell causing it to shrink, this is known as crenation. When a plant cell is placed in a hypertonic solution the cell membrane will pull away from the cell wall, making the plant flaccid, this is known as plasmolysis. When an animal cell is placed in a hypotonic solution, water will rush in to the cell, causing it to swell and sometimes burst. A plant cell placed in a hypotonic solution will also swell due to water rushing in, but will resist rupturing due to the rigid cell wall. Plant cells become more rigid in a hypotonic solution.

Plants can connect with other plants around it. Think of the movie “Avatar”. The scientist say that the trees have a root system that connects with all of the other plants around it. Well, the plants here on earth are very similar. Infact it’s almost the same. The plants on “Avatar” connect with all the plants and they can receive and store data, memories from all of

Plant hormones are chemical signals released by a tissue and delivered to a receptor tissue. Auxin is the hormone most commonly found in plants. Auxin regulates and aids in the development of plants (Kazan 2013). The acid growth hypothesis states that an acidic ph will enhance the effects of auxin in seed development and plant growth. Radish seeds were planted in acidic soil and administered natural and synthetic auxin in order to test for the effect of synthetic auxin in an acidic soil on plant growth. The reason for this experiment is to test whether or not synthetic (man-made) auxin works better than natural auxin in growth development. It was found that the natural kind of auxin works better in an acidic environment than synthetic auxin.

This data shows a strange outcome, in the hypothesis; it says that “If acid is introduced to the seed during germination, then the roots will not grow as long as the seeds that are given water”. This statement proves to be untrue, because the roots grew longer with stronger acid than weaker acid, and in some, cases, grew better with strong acid than it did in water. This may be true because of the acid growth theory. The acid growth theory states that auxins cause the elongation of stem cells by promoting wall loosening. It was determined that this wall loosening is caused by hydrogen ions. This idea and subsequent supporting data gave rise to the acid growth theory, which states that when exposed to auxins, susceptible cells excrete protons into the wall at an enhanced rate, which in turn decreases the pH in the wall. The lowered wall pH then activates the wall loosening process which is essentially doing the same thing as the auxin hormone.