Bio 034 hand-out 2 - Characteristics of Life & Chemistry of Life
1. Characteristics of Life†
1. Organization: Being structurally composed of one or more cells — the basic units of life.
2. Growth and Development: Maintenance of a higher rate of anabolism than catabolism. A
growing organism increases in size in all of its parts, rather than simply accumulating matter.
3. Metabolism: Transformation of energy by converting chemicals and energy into cellular
components (anabolism) and decomposing organic matter (catabolism). Living things
require energy to maintain internal organization (homeostasis) and to produce the other
phenomena associated with life.
4. Homeostasis: Regulation of the internal environment to maintain a constant state; for
example, electrolyte concentration or sweating to reduce temperature.
5. Adaptation: The ability to change over time in response to the environment. This ability is
fundamental to the process of evolution and is determined by the organism's heredity, diet, and
external factors.
6. Response to stimuli: A response can take many forms, from the contraction of a unicellular
organism to external chemicals, to complex reactions involving all the senses of multicellular
organisms. A response is often expressed by motion; for example, the leaves of a plant turning
toward the sun (phototropism), and chemotaxis.
7. Reproduction: The ability to produce new individual organisms, either asexually from a single
parent organism, or sexually from two parent organisms.
The Chemistry of Life†
1. Carbohydrates: are simple compound that produced in plants by photosynthesis. Also known
as Saccharide which means sugar.
Kinds of Carbohydrates:
a. Monosaccharide the most basic unit of biologically important carbohydrates. The
monomer of Carbohydrates. (C6H12O6)
e.g. Glucose, Fructose, Galactose
b. Disaccharide a kind of sugar consisting of two monosaccharides. (C12H22O11)
e.g. Maltose, Sucrose, Lactose
c. Oligosaccharides are polymer saccharides with 3-10 of monosaccharides.
e.g. Raffinose, Chitin
d. Polysaccharides are long carbohydrate molecules of repeated monomer units joined
together by glycosidic bonds.
e.g. Starch, Glycogen, Cellulose
2. 2. Lipids are broad group of naturally occurring molecules which includes fats, waxes,
sterols, fat-soluble vitamins and others. Its major function is as energy source and for
cell structures.
3. Nucleic Acid are biological molecules essential for known forms of life on this planet;
they include DNA and RNA.
- Nucleotide is the monomer of nucleic acid. It has three parts the five carbon
sugar, the nitrogen-containing base and 1-3 phosphate groups.
- The Nitrogen-containing base can be purines (adenine and guanine) or
pyramidines (thymine, uracil and cytosine)
- Pairing of Nucleotides (A-U/A-T and G-C)
4. Protein are any of a large group of nitrogenous organic compounds that are essential
constituents of living cells; consist of polymers of amino acids; essential in the diet of
animals for growth and for repair of tissues; can be obtained from meat and eggs and
milk and legumes.
- Amino Acids are the building blocks of protein.
- There are 20 known amino acids.
- The Central Dogma of Life: DNA RNA Protein
5. Water is a binary compound that occurs at room temperature as a clear colorless
odorless tasteless liquid.
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Prepared by:
Jaycris C. Agnes
The more you know the more amazing the worldseems. STAYCURIOUS.