Essay on Ap Bio Plants

Photosynthesis is essential for a plant to survive. In order to perform photosynthesis, carbon dioxide is needed and is the most important component in the creation of matter. There are two other factors that go into photosynthesis, which are solar energy and water. Both are equally important in order to perform photosynthesis, but they don’t create the majority of the matter in a plant. The carbon dioxide is taken from the atmosphere which has a high concentration of carbon. “During the spring when plants start growing again, concentration drops” (Riebeeck p.5). Plants absorb the carbon dioxide and keep it, in order to grow. Once the carbon dioxide is fixated, glucose is produced and used in the process of cellular respiration.

The leaves of a plant are the main photosynthetic organs and are involved in gas exchange and water transportation throughout a plant (Evans et al, 17). A leaf typically consists of an upper and lower epidermis, the mesophyll cells, veins, guard cells and stomata. The mesophyll cells contains spongey cells which have large gaps between each cell to allow oxygen and carbon dioxide circulation. The mesophyll cells contain palisade cells, which are located beneath the upper epidermis. The palisade cells contain many chloroplasts, which are green organelles. Located in the internal layers of chloroplasts is the pigment chlorophyll which is involved in trapping the light energy in photosynthesis (Evans et al, 17).

      The general characteristics of the plants in these bodies of water have strong and steady roots, or roots that are bendable, depending on how fast the current of the water is. These traits help the plants mainly so they do not get swept away. Plants that

Plants that are adapted to drier climates are called xerophytes (an example if these types of plants are cactus). Some of these plants have adapted small, thick leaves with a reduced surface area. They may also have a thickened cuticle to protect themselves from the environment. The stomata may be sunken into pits. Some xerophytes shed their leaves during the driest seasons and others can store water such as cacti. CAM plants uptake CO2 at night and change it into crassulacean acid that can be broken down during the day for sugars. These plants can close their stomata during the day.

through its ability to hold energy or heat. The response earned a final point for the description of root

Diffusion, osmosis and active transport of substances in and out of the membrane is very important for all types of cells. One example is the root hair cell. These cells are the exchange surface in plants which are responsible for the absorption of water and mineral ions so without osmosis and active transport this would not be possible. The water is taken up by osmosis through the partially permeable membrane. The root hair cells are surrounded by a soil solution which contains small quantities of mineral ions but mainly water, so has a high water potential (slightly less than zero). The root hair cells themselves contain a high quantity of amino acids, mineral ions and sugars inside them (low water potential). Therefore water will move by osmosis from the soil solution and into the root hair cells, going down the water potential gradient.

6) Will water move into or out of a plant cell if the cell has a higher water potential than the surrounding environment? Water will move out of the plant cell because it will follow the gradient to the area of lower water potential.

3) Roots- The portion of a plant that attaches itself to the ground for stability and for some plants a water source.

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.

Tubers are similar to roots, they store energy for the new plant, and helps with vegetative

Water diffuses across the membrane from the region of lower solute concentration (higher free water concentration) to that of higher solute concentration (lower free water concentration) until the solute concentrations on both sides of the membrane are equal. The diffusion of free water across a selectively permeable membrane, whether artificial or cellular, is called osmosis. The movement of water across cell membranes and the balance of water between the cell and its environment are crucial to organisms. ("Diffusion And Osmosis - Difference And Comparison | Diffen"). A semi-permeable membrane known as the cell membrane surrounds the living cells of both plants and animals. Both solute concentration and membrane permeability are taken into account in the ability of a cell to gain or lose water. If there is a higher concentration of solutes in the surrounding solution, water will tend to leave the cell, and vice versa. The membrane forms a selective barrier between the cell and its environment and does not allow toxic substances from the surroundings to enter into the cell (Deena T Kochunni). The selective permeability allows the cell to regulate the flow of necessary substances into and out of the cell. In plants osmosis is also responsible for absorbing water and minerals from the soil by using the semipermeable membrane of the root (Deena T Kochunni). If the extracellular fluid has a lower osmolarity than the fluid inside the cell, it’s said to be

Osmosis is the movement of water molecules from high concentration to low concentration through semipermeable membranes, caused by the difference in concentrations on the two sides of a membrane (Rbowen, L.). It occurs in both animals and plants cells. In human bodies, the process of osmosis is primarily found in the kidneys, in the glomerulus. In plants, osmosis is carried out everywhere within the cells of the plant (World Book, 1997). This can be shown by an experiment with potato and glucose/salt solution. The experiment requires putting a piece (or more) of potatoes into glucose or salt solution to see the result of osmosis (a hypertonic type of solution is mostly used as it would give the most prominent visual prove of

     Plants are autotrophs that mean they are able to synthesize food directly from inorganic compounds, instead of relying on other organisms. They use carbon dioxide gas and water to produce sugars and oxygen

Humans depend on plants in numerous ways. One reason we depend on plants is for consumption. Plants have the unique ability of producing their own food through a process called photosynthesis. In this process, plants are able to produce macromolecules such as carbohydrates that cannot be produced in animals or humans. In humans, the only to gain these macromolecules is to consume plant matter, or consume plant-eating animals (herbivores).