Biology chemical elements and water summary and notes

 

 

 

Biology chemical elements and water summary and notes

 

The following texts are the property of their respective authors and we thank them for giving us the opportunity to share for free to students, teachers and users of the Web their texts will used only for illustrative educational and scientific purposes only.

All the information in our site are for educational uses.

The information of medicine and health contained in the site are of a general nature and purpose which is purely informative and for this reason may not replace in any case, the council of a doctor or a qualified entity legally to the profession.

 

 

Biology chemical elements and water summary and notes

 

- Chemical Elements and Water

2.1.1 State that the most frequently occurring chemical elements in living things are carbon, hydrogen and oxygen.

  • The most frequently occurring chemical elements in living things are carbon, hydrogen and oxygen.

2.1.2 State that a variety of other elements are needed by living organisms including nitrogen, calcium, phosphorus, iron and sodium.

  • A variety of other elements are needed by living organisms including nitrogen, calcium, phosphorus, iron and sodium.

2.1.3 State one role for each of the elements mentioned in 2.1.2.

  • Nitrogen is a major element of proteins and nucleic acid (for DNA and RNA). Calcium is neccesary for bone and tooth formation, blood clotting, and nerve impulse transmission. Phosphorus is also used for bone and tooth formation, and to balance acid and base concetrations in the body. Iron is a part of hemoglobin, a molecule needed to carry oxygen in the blood. Sodium balances both water in the body and acid/base concentration. It also functions in nerve function.

2.1.4 Outline the difference between an atom and an ion.

  • An atom has the same amount of protons as electrons, so it is neutral in charge. An ion has either a positive or negative charge because there are unequal numbers of electrons and protons. A positive ion is called a cation, while a negative ion is called an anion.

2.1.5 Outline the properties of water that are significant to living organisms including transparency, cohesion, solvent properties and thermal properties. Refer to the polarity of water molecules and hydrogen bonding where relevant.

  • Water is transparent which allows light to filter into the oceans. This allows for aquatic plants to absorb light and perform photosynthesis. Since the ancestor of all plants originated in the ocean, the transparency of water has had a immeasurable influence on life as we know it.
  • Water is also cohesive, that is it binds to itself, due to the polarity of the water molecule. The positive, hydrogen side of the molecule binds to the negative, oxygen side of another water molecule. This bond is called a hydrogen bond Thus, a glass of water could be considered one giant molecule, because all of the water molecules inside of it are bonded to one another. This property allows for transport of water against gravity in plants.
  • Water is the universal solvent because it is capable of dissolving many organic and inorganic particles. All the reactions in cells must take place in aqueous solution.
  • Water's polarity also inhibits movement of its molecules. Since all the molecules are connected, they cannot freely move about as other, nonpolar molecules do. Heat, the kinetic energy of molecules, is thus restricted and so water has a high specific heat (it must absorb large amounts of energy in order to change states). This means that water can serve as a temperature insulator, and does so in organisms of all kinds.

 

Source : http://www.oocities.org/mcbatistuta/Topic2.doc

Web site link: http://www.oocities.org/mcbatistuta

Google key word : Biology chemical elements and water summary and notes file type : doc

Author : not indicated on the source document of the above text

If you are the author of the text above and you not agree to share your knowledge for teaching, research, scholarship (for fair use as indicated in the United States copyrigh low) please send us an e-mail and we will remove your text quickly.

 

Biology chemical elements and water summary and notes

 

If you want to quickly find the pages about a particular topic as Biology chemical elements and water summary and notes use the following search engine:

 

 

Biology chemical elements and water summary and notes

 

Please visit our home page

 

Larapedia.com Terms of service and privacy page

 

 

 

Biology chemical elements and water summary and notes