THE SCIENCE OF FOOD
Cancer and nutrition – good nutrition is very important in the management of cancer and thus healthy eating habits are encouraged during this period. Tumors that develop in the stomach or intestines may, however, affect the way the body uses the food that is ingested and may not absorb all the food, although the patient may be seen to be eating enough food. The side effects that may affect eating when one has cancer include vomiting, dry mouth, constipation, mouth sores, loss of appetite among others.
Nutrition therapy is advised for cancer patients to help maintain a good quality life especially if the disease is at advanced stages. The patient is first screened before the treatment to check whether they have any nutritional problem. The main goal of nutrition therapy is to maintain the nutritional health of the patient, provide any missing nutrients, and prevent any problems that may arise due to effects of malnutrition. (Diet, Nutrition and Cancer Program of the National Cancer Institute, 2009, p.95)
CELL CELEBRITIES
Animal cells – they are the most important and most versatile in use in a sub-culture medium. They are the cheapest to sub-culture because they can be easily isolated, require easily achievable growth parameters and are easily visible under the light microscope. The ease of an animal cell sub-culture to be set up and monitored gives the cells the versatility in cell sub-cultures. Most animal cells multiply very fast and their outlines can be clearly seen, normally on the third day after set-up.
They are therefore rated as favorites because of their many uses, compared to other cells. Cell replacement is now possible because of animal cells. They have also been widely accepted and used in gene therapy research and applications. Amputation has been made easy and fast, thanks to the nature of many animal cells of being stem cells hence can differentiate into any type of cell. The resultant cell can then grow and be specific in function and location. (Kim and Ryoo, 2012, p.292)
ENZYMES
Allosteric regulation of enzyme action- Enzyme catalysis begins with the enzyme getting attached to the substrate, then forming the product(s) and the enzyme. The enzyme usually has the active side where it binds to the substrate to catalyze the reaction. The enzyme and substrate only bind in a key-and-lock fashion for the reaction to take place. The active site is specific to the substrate catalyzed.
On the other hand, enzymes can also contain allosteric sites where anywhere on their structure where another molecule can bind the enzyme to control its action. These molecules can either activate or inhibit the action of the enzyme. Allosteric activators increase the rate of enzyme activity while allosteric inhibitors reduce the activity of enzyme action. it is worth noting that unlike active sites that are specifically placed, allosteric sites can be found anywhere on the enzyme structure (Firestone, n.d.)
GENETICS
Deoxyribonucleic acid (DNA) is the genetic material of living organisms that carries the genetic information of the said organism. It is a long chain of deoxy ribonucleotides and is mainly found in chromosomes, mitochondria in animals and chloroplasts for the case of plants. The nucleotides are basically made of a nitrogen base, a sugar, and a phosphate group. Its primary structure results from the linkages of respective purines and pyrimidines through phosphodiester linkages. The secondary helical ring structure is due to the hydrogen bonding between the purines and pyrimidines i.e. Guanine bonds with Cytosine as Adenine bonds with Thymine to maintain the helical structure. These helices then coil around histone proteins to form its tertiary structure.
The bases are in-turn stacked together through hydrophobic interactions and van der Waals forces. It is folded into chromatin in eukaryotic cells. It provides a template on which a complementary strand forms and allows the replication of the parent DNA. This replication facilitates the transcription to RNA and hence maintenance of an organism’s genetic make-up from generation to generation (Chhabra, 2012, n.p).
R VS K STRATEGISTS
R vs. K Strategists – from the video, we can deduce that there are two types of growth characteristics in living organisms. Most simple organisms go through the exponential fast-growing type of growth where they multiply very fast and die off at an equally fast rate and early on in their lives- these are called r survivors. On the other hand, the more complex organisms mostly experience logistic growth where they multiply very slowly and live long for years before dying off- these are termed the k survivors.
R survival is characterized by short generation time, early maturity, unstable environments, small body size, production of many babies, and dispersal of offspring. K survival is characterized by stability in the environment, long life expectancy, the large size of the body, lower number of offspring, and high parental care to the offspring. An example of R survivor are mosquitoes who multiply very fast in stagnant water or during the rains but most die if the water is drained or when the rains recede. A K survivor can be like cows who give birth to one offspring, take the time to care for the calves until they mature up before giving birth again. They also live long and mature up slowly and logistically (Bozeman, 2012, n.p)
References
Firestone, R. (n.d). Enzymatic Inhibition and Lineweaver Burke plots [Video file]. Retrieved from https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&cad=rja&uact=8&ved=0ahUKEwjgwcyWvt_OAhUlK8AKHQE9BkIQtwIIOzAE&url=https%3A%2F%2Fwww.khanacademy.org%2Ftest-prep%2Fmcat%2Fbiomolecules%2Fenzyme-kinetics%2Fv%2Fenzymatic-inhibition-and-lineweaver-burke-plots&usg=AFQjCNG221ytt_3wq7ZpK6am921cAPBQGQ&sig2=4bwHeP22FbPDfMEVrgTGxg
Chhabra, N. (2012, March 2). DNA Structure, Function and Properties [PowerPoint slides].
Diet, Nutrition and Cancer Program of the National Cancer Institute. (2009). Nutrition Reviews, 34(3), 95-95
Bozeman. (2012, April 28).R and K selection [Video file]. Retrieved from http://www.youtube.com/watch?v=Bu6ouKt9zhs
Kim, M. O., & Ryoo, Z. Y. (2012). Feeder Independent Culture of Mouse Embryonic Stem Cells. Reproductive & Developmental Biology, 36(4), 291-294.
