Why are pig ears and chicken cartilage so delicious?! Really delicious warning

Let’s do a little survey first to see how many people like to eat cartilage!

For me, no matter how much meat is on a dish, the first thing I see is always the gristle!

Cartilage is really a peculiar existence. If you say it is a bone, it does not have the hardness that a bone should have. If you say it is not a bone, it undertakes some of the things that bones should do. Look, doesn’t the cartilage in the picture above support the meat?

Today we are going to talk about pig ears, chicken cartilage, the treasure in the palm of your hand, flesh and bones…Oh no, scratch it out and start over, it’s cartilage.

01

Can cartilage turn into bone?

Let's first talk about the relationship between cartilage and bones, which has to start with the embryo. When the human body is in the embryonic stage, organs begin to develop, including bones, but the so-called "bones" at this time are all made of cartilage.

The main components of cartilage are chondrocytes and collagen fibers (this will be mentioned many times later, so remember this point first). When the chondrocytes divide and happen to encounter calcium absorbed from outside the body, the collagen fibers will calcify and harden to form real bones.

This gradual transformation of cartilage into bone also accompanies the development of the human body. The cartilage at both ends of each bone continues to split and calcify, the bones continue to lengthen, and people continue to grow taller until around the age of 20, when their height is basically fixed.

Let me see whose heart was pierced by this sentence~

After a person has fully grown, although the cartilage no longer develops, it will not die. Most of them are a bit like "parasites", distributed at the ends of bones or joints, playing a role in preventing bone friction and buffering.

Cartilage at the ends of bones reduces friction

But there are also some that exist independently, such as nasal cartilage, throat cartilage and ear cartilage, which are left over from the process of human evolution and function like real bones - support and protection. The relationship between cartilage and bones is so complicated that it is hard to cut and untangle.

02

What is cartilage used for?

As mentioned earlier, the main components of cartilage are chondrocytes and collagen fibers, and collagen fibers are composed of a large amount of collagen, so cartilage is milky white in color and has a very elastic texture with a slight hardness.

People who love long-distance running know that the core of running shoes is its cushioning components, and the cartilage between joints also has the function of cushioning and shock absorption. It will slightly deform after being impacted and squeezed, dissipating most of the impact force, and then quickly return to its original shape, avoiding hard collisions between bones and reducing periosteum damage. Among these "cushions", the most well-known is the meniscus in the knee joint.

Cartilage (meniscus) cushions joints

(Copyrighted image from the gallery, no permission to reprint)

When people run and jump, their knees have to bear an impact force that is 2 to 3 times their body weight when they land. If there is no cushion, the femur and tibia will often collide with each other, and there will be a "crackling" sound every time you jump...

My knees are starting to hurt!

The hardness of cartilage allows it to play a certain supporting role: for example, the auricle is supported by cartilage to absorb sound waves; the cartilage in the throat supports the respiratory tract and esophagus; and the nasal cartilage supports the nose.

Some people may ask, since it is for support, why not rely on bones?

As for the auricle and nose wings, these two organs are not large, and they protrude and are exposed to the outside of the body, so bumps and collisions are inevitable. If they were replaced with small bones, they would easily break. On the contrary, elastic cartilage can bend and stretch.

When talking and eating, the respiratory tract and esophagus in the throat will expand and contract repeatedly, so the "scaffold" they need must be elastic, and it must be cartilage.

03

What kind of cartilage are you eating?

Although the components of various cartilages in the body are the same, the proportions and arrangement order of their components are different to meet the needs of different parts. Some have more cartilage cells, while others have more collagen fibers. Some are arranged in a dense network, while others are stacked layer by layer. In medicine, cartilage is divided into three categories based on its function.

1

Hyaline cartilage

This type of cartilage has very little collagen fiber content, so its color is translucent. Due to the lack of collagen fibers, its elasticity and hardness are very weak, so it does not have much cushioning and support. It is usually wrapped around the end of the bone to reduce the friction between the bones during activity.

2

Fibrocartilage

Fibrous cartilage is the opposite of hyaline cartilage - it has more collagen fibers and fewer chondrocytes, and the collagen fibers are arranged in layers, so when it is impacted, it can disperse the impact force to the maximum extent. Joints such as the knee and spine, which are often impacted during exercise, contain fibrous cartilage.

3

Elastic cartilage

The collagen fibers in elastic cartilage are staggered and dense, so it is the most elastic and supportive of the cartilage family. The cartilage in the auricle and throat area belongs to elastic cartilage. If you want to know how elastic it is, just flick your own auricle and you will know.

04

Protect your cartilage!

From the embryonic stage to the end of the developmental stage, bone development is related to cartilage. This is because the chondrocytes in the cartilage have a strong ability to divide and proliferate, so before the age of 30, even if the cartilage is damaged, it can mostly repair itself.

The next sentence will be followed by a "but". Young and middle-aged readers over 30 years old please note:

As people age, the activity of chondrocytes begins to decrease, and collagen fibers gradually harden, making cartilage more vulnerable to injury and difficult to recover. For example, meniscus wear and lumbar disc herniation, which are common in middle-aged people, are symptoms caused by cartilage damage and cannot be completely cured.

Well, by the way, how is your lumbar disc?

Written by Cao Yang

Drawing | Su Yi

WeChat Editor | Ah She Shuang

This article was originally published in the August 2016 issue of Museum magazine.