(Image Caption: The Brain Of A Fruit Fly Contains Many Different Regions Responsible For Processing Sight,

Why we need GMOs to survive climate change

Genetically modified organisms get a bad rap for many reasons, but we’ve actually been genetically altering what we eat since the dawn of human history.

“For 10,000 years, we have altered the genetic makeup of our crops,”explains UC Davis plant pathology professor Pamela Ronald.

“Today virtually everything we eat is produced from seeds that we have genetically altered in one way or another.” (You can read more about Ronald’s thoughts on genetically engineered food here.)

Right now her focus is on rice. It’s one of our basic crops and without it, we would struggle to feed much of the world.

With climate change, we’re seeing an increase in flooding in places like India and Bangladesh, which makes it harder to grow this important food staple.

So Ronald and her lab have developed a flood-tolerant strain of rice. It’s known as Sub1a or “scuba rice” and millions of farmers in South Asia are now growing it in their fields. 

Today is National Food Day, a day dedicated to hunger awareness. But as we focus on food insecurity, we need to talk more about how global warming will make the problem worse.

As our climate continues to heat up, it has huge impacts on what foods we are able to grow. Will our crops be able to survive droughts and floods? The University of California leads six labs that are working to develop other climate-resilient crops including chickpea, cowpea and millet.

Find out what other scientists are doing to improve our food.

a mushroom rainbow to put the fun in fungi. cause they don’t need psilocybin to be magic. and though some mushrooms are coloured as a toxicity warning to predators, many others are brightly coloured to instead attract potential spore dispersers. see this for more on the bioluminescent mushrooms seen here. (photos)

Who is more humble? The scientist who looks at the universe with an open mind and accepts whatever the universe has to teach us, or somebody who says everything in this book must be considered the literal truth and never mind the fallibility of all the human beings involved?

Carl Sagan

Neurotransmitters are chemicals that help in transmitting signals across a synapse. Different neurotransmitters are associated with different functions. Knowledge about these helps us to treat various neurological conditions by either stimulating or inhibiting these production. #neurology #neuroscience #psychiatry #medicine #medstudynotes #medschool #mbbs #unimed #brain #nervoussystem #physiology #medblog #medblr #medstudent https://www.instagram.com/p/BrM4ocsBqJe/?utm_source=ig_tumblr_share&igshid=12tojib83c32d

Astronomers Discover an Entirely New Kind of Galaxy

Astronomers at the University of Minnesota Duluth and the North Carolina Museum of Natural Sciences have identified a new class of ring galaxy. Named PGC 1000714, it features an elliptical core with not one, but two outer rings. It’s the only known galaxy of its kind in the known universe.

Yoshinori Ohsumi wins Nobel prize in medicine for work on autophagy

Japanese cell biologist is named 2016 laureate for his discoveries on how the body’s cells break down and recycle their own components

The Nobel prize in medicine has been awarded to a Japanese cell biologist for discoveries on how cells break down and recycle their own components.

Yoshinori Ohsumi, 71, will receive the prestigious 8m Swedish krona (£718,000) award for uncovering “mechanisms for autophagy”, a fundamental process in cells that scientists believe can be harnessed to fight cancer and dementia.

Autophagy is the body’s internal recycling programme - scrap cell components are captured and the useful parts are stripped out to generate energy or build new cells. The process is crucial for preventing cancerous growths, warding off infection and, by maintaining a healthy metabolism, it helps protect against conditions like diabetes.

Dysfunctional autophagy has been linked to Parkinson’s disease, type 2 diabetes, cancer and a host of age-related disorders. Intense research is underway to develop drugs that can target autophagy to treat various diseases.

Speaking to reporters in Tokyo on Monday, Ohsumi said: “As a boy, the Nobel Prize was a dream, but after starting my research, it was out of my picture.”

He said he chose to focus on the cell’s waste disposal system, an unfashionable subject at the time, because he wanted to work on something different.

“I don’t feel comfortable competing with many people, and instead I find it more enjoyable doing something nobody else is doing,” he added. “In a way, that’s what science is all about, and the joy of finding something inspires me.”

Ohsumi, who was in his lab when he received the phone call from Thomas Perlmann, secretary of the Nobel Committee, admitted to being in a “slight state of shock” about the news.

Continue Reading.

WHAT??? Time to update those textbooks.

Did life begin on land rather than in the sea?

Stromatolites are round, multilayered mineral structures that range from the size of golf balls to weather balloons and represent the oldest evidence that there were living organisms on Earth 3.5 billion years ago.

Scientists who believed life began in the ocean thought these mineral formations had formed in shallow, salty seawater, just like living stromatolites in the World Heritage-listed area of Shark Bay, which is a two-day drive from the Pilbara.

But what Djokic discovered amid the strangling heat and blood-red rocks of the region was evidence that the stromatolites had not formed in salt water but instead in conditions more like the hot springs of Yellowstone.

The discovery pushed back the time for the emergence of microbial life on land by 580 million years and also bolstered a paradigm-shifting hypothesis laid out by UC Santa Cruz astrobiologists David Deamer and Bruce Damer: that life began, not in the sea, but on land.

Stromatolites.Credit: © Ints / Fotolia

Finally got the pure Nile Red in solution, just need to evaporate to get the pure dye.

Interesting fact: Nile Red is a solvatochromic dye. What does this mean? Solvatochromism is the ability of a chemical substance to change color due to a change in solvent polarity, so it has different color in different solvents. Also its emission and excitation wavelength both shift depending on solvent polarity, so it fluoresces with with different color depending on the solvent what it’s dissolved in. 

In this case it was dissolved in dichloromethane.

Autonomic nervous system

Structure and Function of the Sympathetic and Parasympathetic nervous system

The main function of the autonomic nervous system (ANS) is to assist the body in maintaining a relatively constant internal environment. For example, a sudden increase in systemic blood pressure activates the baroreceptors (those are receptors that detect physical pressure) which in turn modify the activity of the ANS so that the blood pressure is restored to its previous level [1].

The ANS is often regarded as a part of the motor system and is responsible for involuntary action and its effector organs are smooth muscle, cardiac muscle and glands. Another system, the somatic (meaning around the body) nervous system, is responsible for voluntary action in which skeletal muscle is the effector.

The ANS can further be divided into 3 parts: sympathetic, parasympathetic and enteric nervous systems [1][2], with the enteric nervous system sometimes being considered a separate entity [2]. Both parasympathetic and sympathetic nervous systems coexist and work in opposition with each other, ultimately maintaining the correct balance; the activity of one being more active depending on the situation. In a normal resting human, the parasympathetic nervous system dominates, while in a tense and stressful situation, the sympathetic nervous system switches to become dominant.

Figure 1. Structure and function of the central nervous system

This article will be focused on sympathetic and parasympathetic activity from the perspective of:

Anatomy

Biochemical

The sympathetic division provides your “fight or flight” whereas the parasympathetic division helps you to “rest and digest”

Anatomy

Higher centers that control autonomic function include the pons, medulla oblongata and hypothalamus [3].

The pons contains the micturition (urination) and respiratory center.

The medulla oblongata contains the respiratory, cardiac, vomiting, vasomotor and vasodilator centres [4].

The hypothalamus contains the highest concentration of autonomic centres [4]. It contains several centres that control autonomic activities, including heat loss, heat production and conservation, feeding and satiety, as well as fluid intake [4].

Figure 2. Locations of the autonomic control centres of the brain

All 3 structures receive input from certain sources by stimulation of nerve fibres resulting from chemical changes in blood composition like blood pH, blood glucose level, blood osmolarity and volume [4]. Notably, the hypothalamus receives input from cerebral cortex and the limbic system, a system that helps control emotional behaviour [3].

Autonomic promoter neurons are neurons that are found in the brain stem, hypothalamus or even cerebral hemispheres that project to preganglionic neurons (discussed below), where they form synapses with these neurons (5). Hence, input from the higher centres can be relayed to the motor neurons (preganglionic and then postganglionic neurons) which subsequently innervate different body tissues. Changes in the input from these centres could result in responses in those tissues.

The primary functional unit of the sympathetic and parasympathetic nervous system consists of a 2 neuron motor pathway (Figure 3), containing a preganglionic and postganglionic neurons, arranged in series.(2) The two synapse in peripheral ganglion. This clearly distinguishes autonomic motor nervous system and somatic nervous system. The somatic nervous system project from the CNS directly to innervated tissue without any intervening ganglia.(6)

Figure 3. Diagram showing the primary functional unit of the ANS

Sympathetic nervous system

Sympathetic preganglionic neurons mainly are concentrated in the lateral horn in the thoracic (T1-12) and upper lumbar (L1 &2) segments of the spinal cord (Figure 4).

The preganglionic axons leave the spinal cord in 3 ways:

Through the paravertebral ganglion

The preganglionic axon may synapse with postganglionic neurons in this ganglion or some axon may travel rostrally or caudally within the sympathetic trunk before forming synapse with a postganglionic neurons in a different paravertebral ganglion.

Through the prevertebral ganglion

Some preganglionic axons pass the paravertebral ganglion (no synapse occur) and form synapse with postganglionic neurons in prevertebral ganglion, also known as collateral ganglion.

Directly to the organs without any synapse

Some preganglionic axons pass through the sympathetic trunk (no synapse) and end directly on cells of the adrenal medulla, which are equivalent to postganglionic cell.

Parasympathetic nervous system

The parasympathetic preganglionic neurons are located in several cranial nerve nuclei in the brain stem and some are found in the S3 and S4 segments of the sacral spinal cord (Figure 4). The parasympathetic postganglionic neurons are located in cranial ganglia, including the ciliary ganglion, the pterygopalatine, submandibular ganglia, and the otic ganglion. Other ganglia are present near or in the walls of visceral organs. Similarly, the preganglionic neurons form synapse with the postganglionic neurons in the ganglia.

Figure 4. Anatomy of the ANS and how its nuerons innervate tissues

After knowing how nerves connect from the CNS to PNS and to different organs, we will now consider some of the neurotransmitters that are being released at different nerve terminals. It is the binding of these neurotransmitters to the receptors on the effectors that leads to biochemical and physiological changes. Some of the neurotransmitters in use are:

For the synapse between pre and postganglionic neurons mentioned above, the neurotransmitter that is released by the preganglionic axon terminal, is acetylcholine. The corresponding receptors are found on the postsynaptic membrane of postganglionic nerves and are nicotinic receptors.

Parasympathetic postganglionic nerve terminals also release acetylcholine.

Sympathetic postganglionic nerve terminals release mostly noradrenaline

The adrenal medulla receives direct stimulation from sympathetic preganglionic innervation, releases mainly adrenaline (80%) and some noradrenaline into the blood stream. In this case, both adrenaline and noradrenaline act as hormones as they are transported via blood circulating system to target organs instead of neuronal pathway.

Strangely, for the sympathetic postganglionic nerves that innervate the sweat glands, the nerves release acetylcholine (normally only by parasympathetic postganglionic nerve) instead.

1. H.P.Rang, J.M.Ritter, R.J.Flower GH. RANG & DALE’S Pharmacology. In: 8th ed. ELSEVIER CHURCHILL LIVINGSTONE; 2016. p. 145.

2. Bruce M. Koeppen BAS. BERNE & LEVY PHYSIOLOGY. In: 6th ed. MOSBY ELSEVIER; 2010. p. 218.

3. Cholinergic transmission [Internet]. 2015. Available from: http://www.dartmouth.edu/~rpsmith/Cholinergic_Transmission.html

4. Bruce M. Koeppen BAS. BERNE & LEVY PHYSIOLOGY. In: 6th ed. MOSBY ELSEVIER; 2016. p. 44.

Image of the Week – February 13, 2017

CIL:40984 - http://www.cellimagelibrary.org/images/40984

Description: Montage image of a brain stem from a Brainbow transgenic mouse. In Brainbow mice, neurons randomly choose combinations of red, yellow and cyan fluorescent proteins, so that they each glow a particular color. This provides a way to distinguish neighboring neurons and visualize brain circuits. These are large caliber axons of the auditory pathway. First Prize, 2007 Olympus BioScapes Digital Imaging Competition. For additional details see: Livet J, Weissman TA, Kang H, Draft RW, Lu J, Bennis RA, Sanes JR, Lichtman JW. Nature. 2007 Nov 1;450(7166):56-62.

Authors: Jean Livet and the 2007 Olympus BioScapes Digital Imaging Competition®

Licensing: Attribution Non-Commercial No Derivatives: This image is licensed under a Creative Commons Attribution, Non-Commercial, No Derivatives License