Will it ever be possible to regrow limbs?
Based upon the limitations of the human body and modern science, however, it's not likely that humans will be able to regenerate missing limbs anytime soon. When salamanders lose a limb, nearby skin cells seal the wound, forming a structure scientists call the wound epidermis.
Although some patients who have a diseased portion of their liver removed are unable to regrow the tissue and end up needing a transplant. Researchers from Michigan State University believe blood clotting factor fibrinogen may be responsible.
It is because mammals have more complex biological structures; limb regeneration would require sophisticated controls to ensure that limbs and organs don't grow out of control. Humans, for example, are already equipped with safety mechanisms to ensure that individual cells don't grow uncontrollably.
Limb replantation is a complex microsurgical procedure that allows patients to have severed limbs reattached or “replanted” to their body. Most patients need limb replantation within hours of experiencing traumatic injuries. Depending on the type of injury you have, surgical specialists can replant some severed limbs.
Humans do have some regenerative abilities. The liver can repair itself. Our blood system is constantly regenerating. And there are cases of people regrowing the tops of severed fingertips (if the wound is left open).
Teeth are the ONLY body part that cannot repair themselves. Repairing means either regrowing what was lost or replacing it with scar tissue. Our teeth cannot do that. Our brain for example will not regrow damaged brain cells but can repair an area by laying down other scar-type tissue .
Our noses and ears are unique compared to the rest of our bodies because they're composed of soft tissue enveloped in cartilage. And it's this soft tissue that keeps growing throughout our entire lives.
Answer and Explanation: The parts of the human body that never stop growing are cartilage appendages, such as the ears and nose.
But adult humans can only regrow skin, most of their liver, and not much else — if you lose an arm or even a finger, a new one isn't going to sprout forth in its place. Scientists believed mammal limb regeneration required nerves and growth factors.
Replantation of an amputated part is best done within 6 hours after the injury. But replantation can still be successful if the amputated part has been cooled for up to 24 hours after the injury.
Can a chopped off hand be reattached?
“Replantation” is the surgical reattachment of a finger, hand, or arm that has been completely separated from a person (see Figure 1). The goal of replantation surgery is to reconnect the separated part. This is done if it can give the patient back better function and appearance.
Generally, humans can regenerate injured tissues in vivo for limited distances of up to 2mm. The further the wound distance is from 2mm the more the wound regeneration will need inducement.
In addition, the Doctor maintains no sense of consistent physicality since he's a completely different physical person every time he regenerates. However, things get a little stickier when we get to his memory, as the Doctor does retain his memories of past events from body to body.
Apparently, Time Lords can only regenerate a maximum of twelve times in a single regenerative cycle. After that, they die. However, the Time Lords have been able to give certain members of their society additional regenerative cycles.
The liver has a unique capacity among organs to regenerate itself after damage. A liver can regrow to a normal size even after up to 90% of it has been removed.
You can still have a fairly normal life without one of your lungs, a kidney, your spleen, appendix, gall bladder, adenoids, tonsils, plus some of your lymph nodes, the fibula bones from each leg and six of your ribs.
The cornea is the only part of a human body that has no blood supply; it gets oxygen directly through the air. The cornea is the fastest healing tissue in the human body, thus, most corneal abrasions will heal within 24-36 hours.
Human embryos develop a tail between five and eight weeks after conception. The tail vanishes by the time humans are born, and the remaining vertebrae merge to form the coccyx, or tailbone.
Loose or sagging skin over a weaker cartilage frame makes ears and noses look longer. You may also find that the rest of your face changes in ways that emphasize your nose or ears. If your cheeks and lips look thinner, your nose might look bigger by comparison.
The cornea of the eye is the only part of our body that does not grow from birth to death because there is no supply of blood .
What is the slowest growing body part?
So, option B nervous tissue is the correct answer.
Eyeballs are the same size when you're born as when you die.
Vestigial organs are parts of the body that once had a function but are now more-or-less useless. Probably the most famous example is … the appendix, though it is now an open question whether the appendix is really vestigial.
Medical uses
Replantation is performed in response to traumatic amputation. Sharp, guillotine-type injuries with relatively uninjured surrounding tissue have the best post-replantation prognosis, with a success rate of 77%.
Replantation surgery is a complex, technically demanding surgical operation in which an amputated body part, most commonly a finger, hand, or arm, is reattached to the body.
Humans can't, but some creatures can re-grow their limbs or tails or even their brains! Sometimes, animals even cast off a part of their body on purpose. They might feel threatened, and they can re-grow it later — this is called autotomy.