MORTALITY.
Mortality, the inevitable truth of life. When a person is born, that time he starts to think about his
death. The most terrifying at the same time interesting fact of life is
mortality.
But the question is , WHY DO WE DIE ?
There may be many reasons for that such as diseases, malnutrition,accidents
etc.
But WHY DO WE DIE when we are old?
The answer lies in the most complicated part of the cell , THE CHROMOSOMES.
In all eukaryotes and mammals DNA is arranged into a structure
called the CHROMOSOMES, capped by a structural component called TELOMERS. These
are kinds of tape at the end of a rope
that maintain its structural integrity.
If a cell replicates for a number of times these telomers becomes shorter because the
cell can’t replicate the DNA to the very end of the strand.
Once the telomers reach at certain “shortness”, it signals the cell to die……..
effectively limiting the numbers of time a cell can divide. It is generally
believed that this also has some effect on lifespan. So this process results to
the death of upper class i.e; tissue, organ, organ system and eventually death
.
Some scientists also believe that ageing is due to the loss
of connection between mitochondria and nucleus of the cell . This results to
ageing and death.
But biological science is so vast that for every “why” there
may not be a valid answer and still we believe in some hypothesis and rough
calculations.
By Aditya Chhoker
11th science.
21ST centuary - the medical era
Ours is a developing era, where we have witness
thousands of discoveries changing our life and living standard.
In 21st century at Washington, some
scientists developed a new pocket
sized syringe that could seal gun-shot wounds within just fifteen seconds.
The syringe called XSTAT, developed by OREGON based
REVMEDX. It injects coated
sponges into wounds.
This device could give survival and spare injured
soldiers from additional pain by recovering wounds faster. The teams used
ordinary sponges and cut them into 1cm circle. Then they injected the bits of sponges into an animal’s injury.
Researchers settled on a sponge made from wood pulp and
coated with blood clotting. They added X-shaped markers that made each sponge
visible on an X-ray image in order to ensure that no sponges are left inside
the body creating enough pressure to stop heavy bleeding.
ANKIT
BHATTI
XI
SCIENCE
Human evolution
Humans have just four basic facial expressions which
correspond to distinct universal emotions. DR. PAUL EKMAN first proposed that there are six basic emotions which are
universally recognized and easily interpreted through specific facial
expressions, regardless of language or culture. Those were happiness, sadness,
fear, anger, surprise and disgust.
Scientists at university of Glasgow, UK have reduced the
list to four. They have deciding that fear and surprise can be combined because
they both cause wide eyes, while anger and disgust compel to wrinkle our noses
automatically in a similar way. The researchers have studied that different
muscles in the face are involved in signaling emotions and time frame over
which each muscle was activated.
Nitesh kataria
Xi science
