Inner Nature: Gustation, the sense of taste
By Vidya Rajan, Columnist, The Times
Lead in paint and gasoline was banned in the 1970s because it causes brain damage by downregulating the production of brain-derived neurotrophic factor (BDNF) [1]. BNDF is an important growth factor for brains to grow and develop properly. Therefore, banning lead from gasoline makes sense – after all chemicals in fumes get breathed in, enter the circulation, and...
Inner Nature: Getting touchy-feely with Somatosensation
By Vidja Rajan, Columnist, The Times
Somatosensation is the ability of the body to sense stimuli, but is not as straightforward as it seems. For example, touch can range from being barely perceptible to being excruciating; an itch that is scratched can go from feeling pleasurable to painful. Percussion and loud music can can be felt as a physical sensation. How does this happen, and is it touch or...
Inner Nature: Good Vibrations – The Science of Hearing
By Vidya Rajan, Columnist, The Times
A disturbance in any medium except vacuum causes vibrations whose energy is transmitted from atom to atom in all directions from the epicenter. These waves encode the amplitude (intensity) and frequency (pitch)(see Figure 1) of the disturbance thus broadcasting information to anyone who can decode the vibrations. Animals, whose very existence depends on whether...
Inner Nature: Eye see colors
By Vidya Rajan, Columnist, The Times
Eyes harvest light reflected from objects. Optic nerves transmit that information to the brain. The brain turns that information into an image. Thus eyes are the intermediary between an object and its perception. Let’s look at them more carefully. Don’t shrink from anatomical detail or biochemistry – this is fun stuff. It’s fun because delving into biomechanical...
Inner Nature: Metamorphosis – Buggy Development
By Vidya Rajan, Columnist, The Times
The growth of a single cell from a fertilized egg, or zygote, to an adult composed of trillions of cells is amazing and magical. This process which scientists, with their knack for understatement, call “development” happens with most eukaryotic organisms – those that have cells with a nucleus and other membranous compartments. Nucleated eukaryotic cells are...
