Great question! Upper airway virus start and do their main business between up until the larynx (not necessarily with same strength on all structures, usually it's more nose/throat/sinus). They do infect our trachea and bronchi, but it's a different kind of cell lining so things are usually not too intense.

From there, we have two things happening at same time:

• the virus is not as efficient getting into your lower airway cells, taking longer (or not! e.g. omicron COVID)

• your immune system is not interested in being kind. The inflammatory response is meant to target infected cells, but it does damage to the surrounding environment and healthy cells.

While your upper airways are meant to be attacked and quickly recover (afterall, it's exposed to the outside world), lower airways are not, they take longer to heal and to return it's inflammatory response back to base levels.

Edit: formatting

People going way out of the way.

What you are describing usually falls into tracheobronchitis diagnosis, which is really common after an upper airway viral infection (common cold, but covid too).

While the overall cold symptoms usually resolve in less than an week, the same infection also happens on your trachea and bronchi, and there it takes a little more time to heal and properly return the mucosa to it's healthy state. Until then, said airways remain mildly inflamated and sensitive, which causes the nagging cough.

As a side note, there are two conditions which may look similar, but whose cause and treatment differ. One is postnasal drip, which happens due to filled sinuses slowly dripping secretion on the throat and making it irritated (mainly while laying down your head). The other is a bacterial tracheobronchitis, which usually has systemic symptoms like fever and purulent coughing and could be thought as a pneumonia-like infection (to make it really simple).

Thats not an arm, the image shows a profile picture of wrist/hand/fingers, but your point stands.

For reference, use your own anatomy: the bone they use to touch the ground is the middle bone of your fingers (thumb excluded) and the finger tip is curled up. From there we have the finger first bone (slightly bent), hand bone (big one), two wrist bones and just the end end of forearm bone.

The main difference between the two species is how the forearm-wrist, wrist-wrist and wrist-hand articulations are used. Chips bend them and gorillas use then in a straight line.

More about fatty liver and cirrhosis:

One of liver basic functions is to store energy, one pathway to it is transforming sugar (and ethanol) in fat. Once you fat storage/usage is skewed, the liver keeps producing and storing fat, which leads to chronic inflammation.

Alcohol, hepatitis virus B and C or even your own autoimmune system cause direct inflammation in your liver.

Inflammation, while reversible, leads to cell damage, which cause (1) repair and (2) scars.

(1) chronic inflammation-repairing leads to increased cancer risk.

(2) scars are mostly irreversible and when accumulated, are called cirrhosis.

How much fatty liver you have before developing cirrhosis depends on genetics, amount and speed of liver damage. For reference, when discussing fatty liver disease, we usually divide it between alcoholic and non-alcoholic due to how much more damage alcohol causes.