Oh Deer Activity

Reflection on Oh Deer Activity

The purpose of this activity was to simulate various factors that affect the deer populations. For the first round, some student were deers on one side and other students were resources on the other sides. The deer-students  had to look for specific resources that they chose before the simulation begins. The resource-students had to choose one resources from water, shelter, food. Through out the simulation, some deer died and became resources while other deer population increased. As the deer prosper, there is not enough resources which caused competition between deers.When there was a shortage of the resources, the deer population significantly decreased. Also, the influence from predators decreased the deer population. For the final simulation, the deers encountered natural disasters such as forest fires, flood, drought which caused decrease in population.
Overall, I think I was the one who was having the most fun running around the field... These activities are more understandable and memorable than long lectures. I wish we had more of these activities for other units as well, but I noticed there was a limit to physical explanation of some Bio units. However, these activities do help a lot remembering general ideas.

Three Laws of Thermodynamics and Metabolism related

1. The Conservation of Energy. The amount of energy in the universe is constant. Energy cannot be created or destroyed but may be converted from one form to another. 

The First Law applies to metabolism in the sense that energy is not free. For example, if the body needs to do a certain amount of work - let's say 5 kJ - the body needs to consume 5 kJ of chemical energy in the form of food to do the 5 kJ of work required. Any energy that is released by an exergonic reaction is absorbed by the surroundings. Conversely, any energy that is stored by an endergonic reaction causes a commensurate decrease in energy of the surroundings.

2. The Law of Entropy. The entropy in an isolated system increases with any changes that occur. All spontaneous events act to increase total entropy.

The Second Law of Thermodynamics is primarily concerned with whether or not a given process is possible. The Second Law states that no natural process can occur unless it is accompanied by an increase in the entropy of the universe.Stated differently, an isolated system will always tend to disorder. Living organisms are often mistakenly believed to defy the Second Law because they are able to increase their level of organization. To correct this misinterpretation, only must simply refer to the definition of systems and boundaries. A living organism is an open system, able to exchange both matter and energy with its environment. Take, for example, the assembly of a virus molecule from its subunits, which clearly involves an increase of order. If the virus is considered an isolated system, this process would be in defiance of the Second Law. However, a virus molecule interacts directly with its environment. The assembly of a virus molecule results in an increase of entropy in the system as a whole due to the liberation of water of solvation from the components and the resulting increase in rotational and translational entropy of the solvent.

3. Absolute Zero. Absolute zero is the temperature (-273°C) at which all thermal kinetic energy ceases. Nothing can be colder than absolute zero. 

Metabolism is unable to proceed at extremely low temperatures close to absolute zero because of the fact that all molecular motion ceases, making chemical reaction unable to occur. Also, enzymes are unable to function at extremely high and extremely low temperatures. 

Carbohydrates

Carbohydrates are an ideal source of energy for the body. This is because they can be converted more readily into glucose, the form of sugar that's transported and used by the body, than proteins or fats can.

Even so, a diet too high in carbohydrates can upset the delicate balance of your body's blood sugar level, resulting in fluctuations in energy and mood which leave you feeling irritated and tired.

It is better to balance your intake of carbohydrates with protein, a little fat and fibre.

- Monosaccharides: simple sugars with multiple OH groups. Based on # of carbons, a monosaccharide is a triose, tetrose, pentose, or hexose. 


- Disaccharide: 2 monosaccharides covalently linked. 


-Oligosaccharides: a few monosaccharides covalently linked. Polysaccharides:polymer consisting of chains of monosaccharide or disaccharide units.

- A monosaccharide can be a aldose (having an aldehyde group at one end) or a ketose (having a keto group, usually at C2)

- Pentoses and hexoses can form rings as ketone or aldehyde reacts with OH group.

- Special type of bond called glycosidic bond joins two carbohydrate molecules: (R-OH + HO-R' ---> R-O-R' + H₂O)

- Condensation (dehydration synthesis) reactions join together smaller sugar molecules to form larger, more complex sugar molecules by forming a glycosidic bond between the smaller sugar molecules resulting in the release of one water molecule per glycosidic bond formed as a product.

- Hydrolysis reactions split complex sugar molecules by adding a water molecule to each glycosidic bond, causing the bond to break and form hydroxyl groups on both product molecules.

- alpha linkage is shaped like "A" or "V", beta linkage is shaped like " / " or " \ "

- Common disaccharides include: maltose [glucose + glucose with a(1→4) glycosidic bond],lactose [galactose + glucose with B(1→4) bond], sucrose [glucose + fructose with a(1→2) bond]

- Plants store glucose in polymer form as amylose or amylopectin, collectively called starch. Glucose storage in polymer form minimizes osmotic effects.

- Amylose is a glucose polymer with a(1→4) linkages. It adopts a helical structure.

- The end of a polysaccharide with an anomeric C1 not involved in a glycosidic bond is called thereducing end.

- Amylopectin is a glucose polymer with mainly a(1→4) linkages, but also has branches formed by a(1→6) linkages. Branches produce a compact structure and provide multiple chain ends at which enzymatic cleavage can occur.

- Glycogen, the glucose storage polymer in animals, is similar to amylopectin, but it has morea(1→6) branches. The highly branched structure allows the rapid release of glucose. The ability to rapidly mobilize glucose is more important in animals than in plants (ex. during strenuous physical activity).

- Cellulose, the material in plant cell walls, consists of long linear chains of glucose with B(1→4) linkages. In cellulose, every other glucose is flipped over due to beta linkages. This promotes intra-chain and inter-chain H-bonds and Van der Waals interactions that cause cellulose chains to be straight and rigid, and pack with a crystalline arrangement in bundles called microfibrils.

- Multisubunit Cellulose Synthase complexes in the plasma membrane produce very strong microfibrils consisting of 36 parallel, interacting cellulose chains. Cellulose gives strength and rigidity to plant cell walls, making them able to withstand high hydrostatic pressure gradients and prevent osmotic swelling.

- Oligosaccharides are sugars that are often covalently attached to proteins or membrane lipids. May be linear or branched chains.

- Lectins are glycoproteins (proteins that contain oligosaccharide chains covalently bonded to polypeptide side chains) that recognize and bind to specific oligosaccharides.

- Selectins are proteins in the plasma membrane with lectin-like domains that protrude on the outer surface of mammalian cells. They are involved in cell-cell recognition and binding.

5 Scientists who contributed to genetics

Gregor Mandel

The theories of heredity attributed to Gregor Mendel, based on his work with pea plants, are well known to students of biology. But his work was so brilliant and unprecedented at the time it appeared that it took thirty-four years for the rest of the scientific community to catch up to it. The short monograph,Experiments with Plant Hybrids, in which Mendel described how traits were inherited, has become one of the most enduring and influential publications in the history of science.

Mendel, the first person to trace the characteristics of successive generations of a living thing, was not a world-renowned scientist of his day. Rather, he was an Augustinian monk who taught natural science to high school students. He was the second child of Anton and Rosine Mendel, farmers in Brunn, Moravia. Mendel's brilliant performance at school as a youngster encouraged his family to support his pursuit of a higher education, but their resources were limited, so Mendel entered an Augustinian monastery, continuing his education and starting his teaching career.

Rosalid Franklin

Rosalind Franklin was born in London on July 25, 1920. In 1947, Franklin went to the Central Government Laboratory for Chemistry in Paris where she worked on X-ray diffraction. In 1951, she moved to King's College, London.Franklin worked on a DNA project that she thought was her own. When the laboratory's second-in-command, Maurice Wilkins, returned from a vacation, however, she learned that he expected her to be his assistant rather than a colleague working as an equal. They had an uneasy relationship, complicated by the fact she was a woman in a "man's world" and their conflicting personalities. Franklin made a number of advances in x-ray diffraction techniques with DNA that allowed her to discover crucial elements in what had become a race between competing research teams to discover the structure of DNA. Franklin produced X-ray diffraction pictures of DNA which were published in Nature in April 1953. This played an important role in establishing the structure of DNA. In fact, many scientists believe Franklin played a larger role than previously acknowledged in the research that led to the 1962 Nobel Prize that was awarded to Maruice Wilkins, Francis Crick, and James Watson for the discovery of DNA's double helix.


F.Sanger

Frederick Sanger(born 13 August 1918) is an English biochemist and a two-time Nobel laureate in chemistry, the only person to have been so. In 1958 he was awarded a Nobel prize in chemistry "for his work on the structure of proteins, especially that of insulin". In 1980, Walter Gilbert and Sanger shared half of the chemistry prize "for their contributions concerning the determination of base sequences in nucleic acids". The other half was awarded to Paul Berg "for his fundamental studies of the biochemistry of nucleic acids, with particular regard to recombinant-DNA".He is the fourth (and only living) person to have been awarded two Nobel Prizes, either individually or in tandem with others.

Paul Berg

Molecular biologist who in 1972 created the first recombinant DNA molecules, and, in doing so, created the field of genetic engineering.

Berg, born in Brooklyn, New York, attended Case Western Reserve University, and in 1952, obtained a Ph. D. in biochemistry. He became a Stanford professor in 1959. Berg, in 1972, combined DNA from the cancer-causing monkey virus SV40 with that of the virus lambda to create the first recombinant DNA molecules. However, upon realizing the dangers of his experiment, terminated it before it could be taken any further. He immediately, in what is now called the "Berg Letter," proposed a one year moratorium on recombinant DNA research, in order for safety concerns to be worked out. Berg later continued his recombinant DNA research, and was awarded the 1980 Nobel Prize in chemistry. In 1991, Berg accepted a position as the head of the Scientific Advisory Committee of the Human Genome Project.

J.Craig Venter

J. Craig Venter, Ph.D., is regarded as one of the leading scientists of the 21st century for his numerous invaluable contributions to genomic research. He is Founder, Chairman, and President of the J. Craig Venter Institute (JCVI), a not-for-profit, research organization with approximately 300 scientists and staff dedicated to human, microbial, plant, synthetic and environmental genomic research, and the exploration of social and ethical issues in genomics.

Dr. Venter is also Founder and CEO of Synthetic Genomics Inc., a privately held company dedicated to commercializing genomic-driven solutions to address global needs such as new sources of energy, new food and nutritional products, and next generation vaccines.

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