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Question 1: What percentage of the brain is made up of water?

Options: A) 55-60% B) 75-80% C) 85-90% D) >95%

Answer: B) 75-80% 

Explanation: On average, our bodies are 57-60% water and our brains 75-80%. Small changes in % brain water can reflect much bigger changes in brain swelling, known as brain oedema. This is a major contributor to poor outcomes following ischemic and hemorrhagic strokes. 


Question 3: The fundamental scientific principle in the operation of a battery is:

Options: A) Dialysis B) Dissociation of Electrolytes 
C) Oxidation-Reduction D) Acid-Base

Answer: B) Dissociation of Electrolytes  

Explanation: An electrolyte is a substance that generates an electrically conducting solution when dissolved in a polar solvent, such as water. The dissolved electrolyte separates into cations (+ charge) and anions (- charge). When an electric potential is applied to the solution, the cations will be attracted to the negatively charged cathode and the anions to the positively charged anode. Batteries usually have a carbon anode, a lithium cobalt dioxide cathode, and an electrolyte containing lithium salt in an organic solvent. 

Question 2: What’s the melting point of Mercury (Hg)

Options: A) -39°C B) 24°C C) 98°C D) 864°C

Answer: A) -39°C

Explanation: Mercury is the only metal in the periodic table that is liquid at room temperature. The only other element that is liquid under standard conditions is the halogen bromine. The nature mercury’s volatility can be explained by its unique electron configuration:
[Xe] 4f
14 5d10 6s2. Electrons fill up all the available subshells, resulting in a strong resistance to the removal of an electron. Thus, mercury behaves similar to noble gases, which form weak bonds and hence melt at low temperatures. 



Question 4: Approximately how many protein-coding genes make up the human genome?

Options: A) 1'000 B) 8'000 C) 17'000 D) 24'000

Answer: D) 24’000 

Explanation: There are 23’000-25’000 protein-coding genes in humans. Additionally, there are over 20’000 RNA coding genes, which are extensively involved in regulating gene expression. Only 1.5% of the human genome is made up of coding regions. The rest constitutes regulatory DNA sequences, non-coding RNA, long/short interspersed nuclear elements (LINEs/SINEs), introns  and other DNA sequences that are not fully understood.

Introns are noncoding regions found interspersed within a gene.  The coding regions in a gene are called exons. After a gene is transcribed into messenger RNA, introns are removed through a process called splicing, before the mature messenger RNA can be translated into protein. Historically, introns have been described as ‘junk’ DNA, due to their non-coding properties. However, more recent research has recognised the important role that introns play in regulating gene expression.

It has long been hypothesised that organism complexity must correlate with the size of the genome. While that holds some truth, it is really the average number of introns per gene that positively correlates with organism complexity. An increased number of introns increases the possibility for alternative splicing events, where some intronic regions can remain in the mature messenger RNA, or some protein-coding exons are removed from the sequence. Alternatively spliced RNA codes for a slightly different protein isoform. This enables expansion of the proteome without the need to expand the genome. For example, the Drosophila protein DSCAM (Down’s syndrome cell adhesion molecule) has 38’000 isoforms, generated by different combinations of alternative splicing events.


Question 5: What is the range of the visible spectrum?

Options: A) 120nm-380nm B) 380nm-740nm
C) 740nm-1050nm D) 1050nm-1370nm

 

Answer: B) 380nm-740nm

Question 6: Which of the following is used to make magnet?

Options: A) Alnico B) Stainless Steel C) Duralumin D) Magnalium

Answer: A) Alnico

Explanation: Alnico is a family of iron alloys, which, in addition to iron, are composed primarily of aluminium (Al), nickel (Ni), and cobalt (Co). Alnico alloys are ferromagnetic and can be used to make permanent magnets. 



Question 7: Which of the following diseases is not caused by viral infection?

Options: A) Ebola B) Dengue Fever C) Marburg Haemorrhagic Fever D) Tuberculosis

Answer: D) Tuberculosis

 

Explanation: Tuberculosis (TB) is a disease caused by the bacterium Mycobacterium tuberculosis. TB mainly affects the lungs, causing chronic coughing with bloody mucus and fever.

Ebola is caused by the ebolavirus; the initial symptoms include fevers, muscular pain and headaches. Vomiting, diarrhoea and rashes usually follow, along with decreased function of the liver and kidneys. During this period, there is an increased risk of internal and external bleeding. On average, ebola kills ~50% of those who become infected.

Marburg virus infection causes similar symptoms to those of ebola, with haemorrhage, fever and widespread musculoskeletal pain. Ebola and Marburg viruses have been recognised as risk 4 pathogens by the WHO (World Health Organisation).

The dengue virus is transmitted through the bite of a carrier mosquito. Over 50% of cases of Dengue fever are asymptomatic, and the typical flu-like symptoms can be readily controlled (fatality rate of <1%). However, a severe form of Dengue fever, known as Dengue Haemorrhagic Fever, is characterised by haemorrhagic manifestations and has a mortality rate of up to 20% in the absence of good medical care. 


Question 8: Where are mesons found?

Options: A) X-Rays B) Laser Beams
C
) Cosmic Rays D) Gamma Rays

Answer: C) Cosmic Rays

Explanation: Mesons are subatomic particles composed of one quark and one antiquark, bound together by strong interactions. Outside the nucleus, mesons appear in nature only as short-lived products of very high-energy collisions between particles made of quarks, such as cosmic rays. 


Question 10: Which is the most common isotope of Hydrogen?

Option: A) Protium B) Deuterium C) Tritium

Answer: A) Protium 

Explanation: With 99.98% abundance, protium, or hydrogen-1, is the most common isotope of hydrogen. Its nucleus is made up of just one proton. The deuterium isotope nucleus contains an additional neutron, while the tritium isotope nucleus has two additional neutrons. 

Question 9: The Beer-Lambert Law is related to:

Options: A) Reflection B) Refraction C) Interference D) Illumination

Answer: D) Illumination

Explanation: The Beer-Lambert law uses the measurement of the absorbance of light shone across a length of a given solution to calculate its concentration.  




References

1) En.wikipedia.org. (2020). Alnico. [online] Available at: https://en.wikipedia.org/wiki/Alnico [Accessed 2 Feb. 2020]. 

2) American, S. (2020). What is junk DNA, and what is it worth?. [online] Scientific American. Available at: https://www.scientificamerican.com/article/what-is-junk-dna-and-what/ [Accessed 2 Feb. 2020].

3) Anon, (2020). [online] Available at: https://www.quora.com/What-is-spectrophotometry-and-application-of-it [Accessed 2 Feb. 2020].

4) Medical News Today. (2020). Cerebral edema: Symptoms, causes, treatment, outlook. [online] Available at: https://www.medicalnewstoday.com/articles/322475.php [Accessed 2 Feb. 2020].

5) MedicineNet. (2020). Definition of Dengue hemorrhagic fever (DHF). [online] Available at: https://www.medicinenet.com/script/main/art.asp?articlekey=6627 [Accessed 2 Feb. 2020].

6) Cdc.gov. (2020). Ebola (Ebola Virus Disease) | CDC. [online] Available at: https://www.cdc.gov/vhf/ebola/index.html [Accessed 2 Feb. 2020].

7) Feng, Z., Higa, K., Han, K. and Srinivasan, V. (2017). Evaluating Transport Properties and Ionic Dissociation of LiPF6in Concentrated Electrolyte. Journal of The Electrochemical Society, 164(12), pp.A2434-A2440.

8) En.wikipedia.org. (2020). Isotopes of hydrogen. [online] Available at: https://en.wikipedia.org/wiki/Isotopes_of_hydrogen [Accessed 2 Feb. 2020].

9) En.wikipedia.org. (2020). Marburg virus. [online] Available at: https://en.wikipedia.org/wiki/Marburg_virus [Accessed 2 Feb. 2020].

10) En.wikipedia.org. (2020). Mercury (element). [online] Available at: https://en.wikipedia.org/wiki/Mercury_(element) [Accessed 2 Feb. 2020].
11) 
En.wikipedia.org. (2020). Meson. [online] Available at: https://en.wikipedia.org/wiki/Meson [Accessed 2 Feb. 2020].

12) Encyclopedia Britannica. (2020). Meson | subatomic particle. [online] Available at: https://www.britannica.com/science/meson [Accessed 2 Feb. 2020].

13) Tang, S., Shen, H. and An, O. (2020). Alternative splicing - Latest research and news | Nature. [online] Nature.com. Available at: https://www.nature.com/subjects/alternative-splicing [Accessed 2 Feb. 2020].

14) Usgs.gov. (2020). The Water in You: Water and the Human Body. [online] Available at: https://www.usgs.gov/special-topic/water-science-school/science/water-you-water-and-human-body?qt-science_center_objects=0#qt-science_center_objects [Accessed 2 Feb. 2020].

15) Medlineplus.gov. (2020). Tuberculosis | TB | TB Test | MedlinePlus. [online] Available at: https://medlineplus.gov/tuberculosis.html [Accessed 2 Feb. 2020].

16) En.wikipedia.org. (2020). Visible spectrum. [online] Available at: https://en.wikipedia.org/wiki/Visible_spectrum [Accessed 2 Feb. 2020].