The Role of Water in Living Organisms
Water is one of the most abundant molecules on planet earth; it is
found in vast amounts not only in earthly enviroments (oceans, lakes
and rivers), but is also present in the atmosphere, and as solid ice
in the two poles. Consequently it is rather logical that water plays
an important role in biological life: the origins of life occurred in
water and life itself wouldn't be able to continue in it's absence .
I will now describe the structure of a water molecule. It consists of
an oxygen atom covalently bonded to two other atoms of hydrogen. The
two bonds form a 105 degrees angle with eachother, but for the reason
that oxygen is more electronegative than hydrogen, the shared electron
charge of the covalent bond is distributed more towards this atom,
making the water molecule weakly polar. Always due to reasons related
to the distribution of the charge water is able to form weak hydrogen
bonds, both to other water molecules and also to many other types of
polar molecules. This is a very essential characteristic, which allows
water to have unique properties.
Water's ability to form weak H-bonds to other polar molecules allows
the anion and the cation of a polar-bonded molecule to separate from
one another, and go into solution. Evene large molecules such as
proteins can form enough H-bonds with water to become soluble, also
the catalytic activity totally depends upon the soluble nature of the
enzyme molecules. Water, takes up a large space in cells, which are
the single components of the human body. This is a physical
demonstration, of how water is essential for life to be happening. The
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...oupled with the "transpirational
pull" generated by evaporation of water from leaves which acts upon
the continuos column of water in xylem tissue, allow water and
dissolved minerals to be supplied to plant tissues up to 100 metres
above the ground.
Another property of water is its transparency to visible light. light
can penetrate water to a considerable depth, provided the water is
free of suspended, particulate matter. Different wavelengths of light
penetrate to different depths. Red and yellow light only travel to a
maximum of 50 metres depth, whilst blue and violet light can reach 100
metres. This allows large volumes of water to serve as habitats for
photosynthetic organisms. On land, light can easily penetrate plant
leaf epidermal tissues, which are 90 % water, to reach the underlying
photosynthetic cells.
...hroughout the Eelgrass. Excess water in the form of vapor is disposed of through stomata on the leaves. The gas exchange, root, and shoot systems are used in this exchange because the stomata release the excess water in the form of water vapor, which was first absorbed by the roots in the root system, then transported through the xylem in the shoot system throughout the eelgrass. Another exchange that goes on in Eelgrass is nutrients to plant cells. Again the gas exchange, root, and shoot systems are used. Nutrients are absorbed by the roots and made through photosynthesis; stomata take in carbon dioxide which is used along with light, water, and other nutrients previously stored to make more. Nutrients are carried throughout the plant to plant cells by the phloem. Homeostasis is the balance of systems in organisms and it’s very important to keep them in balance.
because this is what makes the plant "stand up" and acts as a form of
Some plants live in conditions where the spectral quality of light may be different to that received by plants living on the land. Algae which live in surface waters tend to be green and contain more or less the same pigments as land plants since they exist under similar light conditions. Algae living lower in the water receive more blue light than red because red light has a relatively long wavelength and cannot penetrate water as well as blue light which has a shorter wavelength and more energy than red light. Brown algae, which may be found deeper in the water than green algae, have combinations of pigments which enable them to
potato. To make it a fair test I will make sure that the tests will be
The light is absorbed by the chloroplasts to produce the chlorophyll. The chemical & word equation for photosynthesis is stated below: Sunlight Carbon dioxide + water -----------------> Glucose + oxygen Chlorophyll S 6CO2 + 6H20 -----------------> C6H12O6 + 6O2 C Light in photosynthesis Photosynthesis cannot take place without light, as light is one of the factors by which the green plant photosynthesises (makes its own food source) Light provides the plant with energy to make the chlorophyll which in turn absorbs the light. From this it can be said that the more light a plant is provided with (the more of a limiting factor is takes in) then the higher the rate at which the pond weed, or any plant, will give off a product of photosynthesis i.e. glucose or oxygen. From this the knowledge can be gained that depriving the aquatic plant I will be investigating of all light would be a pointless investigation, as no outcome could be measured.
The Biological Importance of Water as a Solvent and as a Medium for Living Organisms
Water has importance inside cells and outside. This may be because of its chemical and physical properties; it can be found naturally in all three of its states. At room temperature water is in a liquid state, It boils at 100ºC and freezes at 0ºC. However its molecules are bonded together by hydrogen bonds, this raises it's melting and boiling points, e.g. its boiling point would be -120ºC rather than 100ºC. Water can also be used as a solvent because of it polarity. Many things will dissolve in it, and more reactions take place while in solution with water.
Water Relations in Two Plant Tissues Results: Table 5 Table to show the sucrose concentration and water potential of each tissue. The sucrose solution was extrapolated from graph 1, which shows the percentage change of mass of the tissues when immersed in the different sucrose solutions. A line of best fit was drawn, where the line of best fit intercepts the x-axis (concentration of sucrose solution) is the sucrose concentration of the tissue because at this point there is no mass loss of gain (read off of y-axis).
Osmosis is the passage of water molecules from a weaker solution to a stronger solution through a partially permeable membrane. A partially permeable membrane only allows small molecules to pass through, so the larger molecules remain in the solution they originated in. Solute molecule [IMAGE] [IMAGE] Water molecule [IMAGE] The water molecules move into the more concentrated solution. When water enters a plant cell it swells up. The water pushes against the cell wall and the cell eventually contains all that it can hold.
How do plants resist being uprooted during typhoons? How do they absorb water? The answer lies on a particular plant structure, which is called the root. Basically, a monocot and a dicot root differ but also have common parts like the xylem and the phloem. Through examining the roots using the light microscope, the students would hopefully be able to understand how the root is designed to perform its vital functions. A root tip basically has 4 main regions, the root cap, the meristematic region, the region of cell elongation, and the region of cell differentiation. These parts are all essential for a root to function properly, thus further stressing its importance in t...
This transpiration process occurs as plants absorb water through their roots and stems which affects the
The water molecule is a very small one but because of its unique properties it behaves like
Plants also had to adapt on the surface in order to survive the climate change of moving onto land. The changes made to the surface of plants are most closely observed by their formation of a cuticular wax. This waxy cuticle is impermeable to water and acts as a method of controlling plant’s water intake. It can be made thinner or thicker depending on the plant’s needs and the environment at the time, changing in response to droughts or excessive amounts of rain.
Water comes from a variety of sources. All beverages, juices and fluids we consume are sources of water for our body. Even solid food contains water. Vegetables such as cucumber, lettuce and celery may have up to 90% water. Protein rich food such as meat and fish could contain two-thirds to one half of their weight of water. Even carbohydrates like grains, although do not appear to be watery could contain water as much as one third of their weight. Fats such as butter or margarine contain very little water. Some water may come from within our body because of energy metabolism but the amount is insignificant.
Water is the most vital part of life. Water is needed from humans, to plants and other organisms, and to do basically everything. Water allows our bodily functions to work and to remove waste from our bodies. Plants need water to grow, and humans need plants to gr...