The signal is the same; it’s the starting and ending points that differ.

The touch activates local sensory neurons, which generate an action potential. This signal is transferred to the somatosensory cortex of the brain (soma = body, literally the body sensing part of the brain). There is point-for-point correspondence of each area of the body to specific points on the somatosensory cortex. This is called somatotopy, and is how the brain knows which part of the body is being touched.

Read about it here.

I would not agree that the vomiting reflex doesn’t protect the animal. Clearly, the sooner the irritating substances are cleared of the gastrointestinal tract, the better for the animal’s health. The animal doesn’t have to « know » anything to be protected by a reflex, just like taking your hand off the hot stove protects you before the brain event feels the heat.

I would also not agree that the vomiting reflex of animals was evolved by the microorganisms, because that’s not how evolution works. The development of the sensory apparatus needed to sense the irritation, and then to provoke the necessary contractions to induce the vomiting is the result of the animal (not the microorganisms) population’s genetic changes and selection, with the animals that developed that reflex being fitter to face off infections.

I’ll agree that some microorganisms may have evolved to produce increasingly irritating substances so as to provoke vomiting with evermore efficiency because this could benefit them with the dispersion aspect.

There are 2 aspects at play here.

Microorganisms and/or their toxins do their actions on stomach cells and cause cellular destruction, which creates pain that is perceived as stomach cramps.

The destruction causes inflammation of the stomach mucosa. The afferent portion of the vagus nerve will be stimulated by either :

… the inflammation, like with Fusarium infection with its vomitoxin.

… or by the toxin itself, like with Bacillus infection with its emetic toxin.

Either way, a nervous signal is sent to multiple structures in the hindbrain, including the reticular formation and the dorsal motor nucleus of the vagus. These respond by sending an efferent influx through the vagus nerve to have the stomach muscles contract, in an effort to induce the emetic reflex (vomiting). This also causes stomach cramps.

Vomiting the microorganisms and their toxins is a protective mechanism that helps prevent the passage of theses substances to the small intestines, where they could be absorbed to the blood stream and cause much more damage.

Yes. Having four copies of a chromosome is called a tetrasomy.

You can see it in humans with 48,XXXX individuals, who are females with 4 X chromosomes instead of the regular 2.

Yes, but it’s not a timed response as much as a temperature response (and admittedly, the cold always comes after the warmth, from the leaves point of view).

We know that carotenoids are present all year round and are seen in autumn because of the chlorophylls degradation. In contrast, anthocyanins are mostly produced in autumn, in response to cold stress. This could be because these pigments have a protecting effect against cold.

About carotenoid synthesis.

About anthocyanins and cold stress.

The pigments mainly serve their purpose during the mature part of the leaf cycle.

Having carotenoids (orange pigments) and anthocyanins (red pigments) on top of chlorophylls allow the leaf photosystems to absorb light in the 500-600 nanometers range (green light), which would be lost had it only be chlorophylls.

Once the mature part is over and the shorter, colder days of autumn set in, the pigments are metabolised for food / energy. The chlorophylls are metabolised first, revealing the other pigments that were already there.

As was said, it’s not about scientists building cells from scratch. It’s using existing cells with simple genomes and stripping it down to the essentials.

This is done to study which genes are and are not essential to life.

Read about it here.

It depends.

The organism with the smallest genome for naturally occurring cellular organisms is probably Mycoplasma genitalium.

There are synthetic cells that have a smaller genome, but these are lab-made, not free-living.

Then there are viruses; are they life forms ? That’s another debate. If you include viruses, then Circovirus probably has the smallest genome.

Pushing it to the extreme, you’d have viroid “genomes”, which are only a couple hundreds nucleotides, but that might be really pushing the definition of what a life form is.