Some Qs. people asked me on science and my replies to them - Part 100

                                                                     Interactive science series

Q: Why do we feel lots of pain when a paper edge cuts our fingers?

Krishna: Because of lots of nerve endings, which is a safety mechanism, according to nature!  We've got more pain receptors in the tips of our fingers than almost anywhere else in the body. These nerve endings are called nociceptors,  and they warn the brain – through the sensation of pain – about high temperatures, dangerous chemicals, and pressure that could break the skin.

The paper edges also play a role,  as they are not as smooth as they might appear from a distance, and can leave a rough trail of destruction on the skin, rather than a good, clean nick. The paper edge cuts like a saw, not like a smooth knife.  These wounds leave chemical coded particles irritating the wound. Paper cuts are usually not deep enough to activate the body's natural defence mechanisms – such as blood clotting and scabbing – so the damaged nerve endings in our fingers are left exposed, the open wound is flexed and strained every time we use our hands until the skin is repaired.

Q: Why do we feel nervous sometimes or have butterflies in the stomach?

Krishna: When you face a difficult situation, you feel nervousness. It is due to the release of the stress hormones which prepare you for “Fight or Flight” situation (primitive survival reflex). The stomach muscles get extra-sensitive during the fight-or-flight response, and that's partially what causes the butterflies. Neurons along the brain-gut axis let the stomach know when we're freaking out about something .

Your nervous system is split into the (Central Nervous System) CNS and the (Peripheral Nervous System) PNS. The PNS is further divided into the autonomic nervous system - ANS and the somatic nervous system - SNS.

The human body is capable of looking after itself without too much voluntary thought - a process run by the autonomic nervous system (ANS). ANS facilitates unconscious control and regulates bodily functions such as the heart rate, digestion, respiratory rate, pupillary response, urination, and sexual arousal. If people perceive their life to be stressful, exciting, alarming, and all of the different stimulants found in drinks and food, we could be potentially activating the Sympathetic Nervous System all day, from the moment we get up to the moment we go to bed. This activation results in the release of stress hormones cortisol, adrenaline and nor-adrenaline.

The ANS can be split into two roughly equal branches – the sympathetic and the parasympathetic,  the “fight-or-flight” and the “rest-and-digest” branches. Both branches of the ANS are constantly active, and act in opposition to each other. The nervous system is what makes you feel tired after dinner. 

The sympathetic (“fight-or-flight”) system is responsible for increasing your heart rate, while the parasympathetic (“rest-and-digest”) system decreases it. So, the rate at which your heart is beating is the balance of the activity of the two branches of the ANS. The dominance of the parasympathetic branch is why you feel content and sleepy after a giant lunch. Quite of bit of blood flow from the heart is directed to the stomach, and your ANS encourages you to sit down for a bit to let digestion take place.

So what’s this got to do with butterflies? One of the major roles of the ANS is to prepare you for what it thinks is about to happen. This gives an evolutionary advantage, since if you see a snake about to attack you, you don’t want your valuable oxygen-filled blood to be busy with your last meal. Ideally you would want this blood to be temporarily redirected to muscles in your legs so that you can run away slightly faster. So, your “fight-or-flight” sympathetic system kicks in and becomes dominant over parasympathetic activity. This also causes a release of adrenaline, which both increases your heart rate (to pump more blood and faster), releases huge amounts of glucose from the liver, and shunts blood away from the gut. The blood is redirected towards the muscles in the arms and legs which makes them ready to either defend you, or run away faster – the “fight-or-flight” that you’ll probably be familiar with.

However, this acute shortage of blood to the gut does have side effects – slowed digestion. The muscles surrounding the stomach and intestine slow down their mixing of their partially digested contents. The blood vessels specifically in this region constrict, reducing blood flow through the gut. While adrenaline contracts most of the gut wall to slow digestion, it relaxes a specific gut muscle called the “external anal sphincter”, which is why some people report a pressing need to visit a bathroom when they’re nervous. This reduction in blood flow through the gut in turn produces the oddly characteristic “butterflies” feeling in the pit of your stomach. It senses this shortage of blood, and oxygen, so the stomach’s own sensory nerves are letting us know it’s not happy with the situation.

Q: Does remission in cancer mean a complete cure?

Krishna: There are two types of remission. 

1. Partial remission means the cancer is still there, but your tumor has gotten smaller -- or in cancers like leukemia,  you have less cancer throughout your body. Some doctors tell patients to think of their cancer as “chronic,” like heart disease. It’s something you will need to continue to check. If you’re in partial remission, it may mean you can take a break from treatment as long as the cancer doesn’t begin to grow again.
2. Complete remission means that tests, physical exams, and scans show that all signs of your cancer are gone. Some doctors also refer to complete remission as “no evidence of disease (NED).” That doesn’t mean you are cured.

There is no way to tell whether all the cancer cells are completely gone. That is why we don't use the word 'cure' with regard to cancer. If cancer cells come back, it usually happens within the 5 years following the first diagnosis and treatment.

Some cancer cells can remain unnoticed in the body for years after treatment. If a cancer returns after it has been in remission, it’s called a “recurrence.”  Every situation is different, and there’s no way to predict what will happen.

When oncologists use the word “remission”, or “complete response”, as in, “You are in remission”, or “You have had a complete clinical and radiographic response to treatment”, they denote this uncertainty in cancer treatment. 

Q: If I have a scientific theory, how can I tell it to the world and make it accept it?

Krishna: The best way is to publish it with evidence in a high quality peer reviewed journal. If your results can be verified and reproducible, it will be accepted by the scientific community as a valid theory.

Q: What makes a theory 'scientific'?

Krishna: Scientific methods and methodologies followed to form it, validate and accept it.

Q: What is the scientific reason for "Milk Miracle"? Do Gods really drink milk?

Krishna: Scientists have this explanation: When you put a spoon full of milk before a statue, (the spoon and milk should come in contact with the statue), after the milk disappeared from the spoon, it coated the statue beneath where the spoon was placed. Capillary action is the explanation. The surface tension of the milk was pulling the liquid up and out of the spoon, before gravity caused it to run down the front of the statue.

No, statues don't drink milk and no miracle is involved.

Q: What bothers you with regard to human nature in relation to science?

Krishna: What went wrong in ‘human imagination’ in the initial stages of mental growth?? That made humans believe in irrational things?

Lack of true information. Facts. Data. Critical thinking.

Now that we are getting them or have them, why can’t we use them or why should we still follow the old ways of thinking? Like neanderthal’s thought and imagined?

Why can’t we have a better understanding of the world around?

Why is the human mind refusing to grow and develop a scientific way of thinking now too?

Yes, why?!

Q: Why do some scientists talk about philosophy? Are they doing justice to their science by entering another arena?

Krishna: Those famous scientists  you mentioned talk about philosophy because they want to sell books.

If scientists talk about science, listen to them. If they talk about philosophy, just hit the ignore button. Opinions don't count in science and if people start talking about things they are not experts of, you need not listen to them.

Q: Does Quantum Mechanics say God exists?

Krishna: Quantum Mechanics doesn't deal with God. Period!

Q: What is the difference between these words: Science, religion, philosophy? Which one is the best?

Krishna: Science deals with facts, religion with fiction and philosophy with something in between the two. 

Science is the best for those who love reality, religion for those who love fiction and philosophy for those who love to sit on the wall in between science and religion!

Q: If ghosts are fake, then how come I saw my dead dad?

Q: What is teh best way to democratize the truth?