What are the three types of cartilage?
Written by Jose Emmanuel Cisneros
The three types of cartilage in the body include elastic, hyaline, and fibrocartilage. These three tissues differ in their strength, body location, and extracellular matrix (ECM).
Cartilage is a connective tissue denser than the blood but less dense than the bone. It has chondrocytes that produce extracellular matrix (ECM). It contributes to the growth of cells and tissues. These materials lie in spaces called lacunae housing eight chondrocytes each.
This connective flesh in the body is flexible and avascular. Thus, this tissue can support, cushion organs, and aid body locomotion.
At a microscopic level, each body tissue has its particular characteristic. Its difference in appearance and (sometimes) function aid histologists in determining their importance.
1. Elastic Cartilage
It also goes by its other name, yellow cartilage. The elastic fiber and collagen fiber network contribute to its color. These fibers usually give off yellow color. And this is all thanks to the principal protein making up the fiber called elastin.
This one resembles the structure of hyaline cartilage. But the only difference is the number of elastic fibers: the elastic has more of this. This characteristic enables the tissue to have great flexibility that withstands continuous bending.
2. Hyaline Cartilage
It encompasses most of the cartilages of the body. They consist of a translucent protoplasm studded with one or two round nuclei. Sometimes, you can see interlacing filaments on the granulated matrix.
The hyaline contains collagen fibers the most, attributing to the glass-like appearance. It has no nerve or blood vessel network. This function makes it a perfect cushion for covering different organs.
3. Fibrocartilage or Fibrous Cartilage
This tissue contains the most collagen fiber among the three, with Type I and Type II. It has a mixture of fibrous connective tissue and cartilaginous tissue.
The fibrous tissue gives it flexibility and toughness. Meanwhile, the cartilaginous tissue gives it elasticity. The fibrocartilage belongs to the densest cartilage among the three. It is also the only cartilage having type I collagen besides type II collagen.
How does cartilage form?
A cartilaginous tissue contains chondrocytes, fibers, and extracellular matrix (ECM). These materials help in cartilage formation by attracting water. It would then give its characteristic shape and property.
They produce collagen, proteoglycans, glycoproteins, and hyaluronan. These macromolecules constitute the shape and structure of the tissue.
Chondrocytes vary among the different types of cartilaginous tissues. It depends on how much matrix the cell produces. The chondrocytes clump up together and form cell nests within the cavities of the tissue.
Extracellular Matrix (ECM)
This constituent differentiates connective tissues from others. They originate from the secretions of the chondrocytes. They also have two elements: the fibers and the ground substance.
The definition of the fibers will appear in the following section. The ground substance contains water, adhesion proteins, and polysaccharide molecule.
The cell adhesions serve as a glue in function. They enable the attachment of connective tissue cells (chondrocytes) to the matrix fibers.
Meanwhile, the polysaccharides help trap water as they become more complex structures. The more the polysaccharides become abundant, the more they make the matrix fuller. The number of polysaccharides determines the density of the tissue. Their consistency ranges from fluid to gel-like.
The fibers found in cartilages include collagens (white), elastic (yellow), and reticular fibers. Collagen contributes to its high tensile strength. Meanwhile, elastic fiber aids in stretching and recoiling motion. Reticular fibers create a cushion for soft tissues.
The monomers of these fibers originate from the chondrocytes of the tissue. They link together like other proteins and carbohydrates to form these fibers.
All these substances contribute to the shape and density of the connective tissue. The following shows the order of cartilages (from less dense to densest):
Hyaline Cartilage ➡️ Elastic Cartilage ➡️ Fibrocartilage
Where are they located?
In general, cartilages live most in the tips of body organs. This way, they would have more range in their cushioning and connecting abilities. Here are some lists of body parts where we can find the three types of this connective tissue:
· Hyaline Cartilages
This cartilaginous flesh has the most amount in the body. One reason that contributes to this attribute points to the procreation of the body. It comprises the early embryonic skeleton of a baby. Examples include:
- the bone ends in free moving-joints
- rib ends
· Elastic Cartilages
The more pliable of the three, it resides in parts where it undergoes tension. It also helps in bouncing off vibrations traveling in the specific body canal. Example body parts are:
- epiglottis (near the larynx region)
- pinnae (external ear location)
- the auditory tube of the middle ear (Eustachian tube)
· Fibrocartilages (Fibrous Cartilages)
The densest cartilaginous tissue of the bunch. This asset helps protect and cushion organs sensitive to impact (like the bones). Some organs with fibrocartilage are:
- intervertebral disks (spinal column)
- pubis symphysis (pelvis location)
- the joint between the manubrium and sternum (rib location)
- temporal mandibular joint (lower jaw location)
- menisci (knee location)
What is the strongest cartilage?
According to doctors, the strongest cartilage found is fibrocartilage. The reason for this leads to its contents. It has a thick layer of alternating structures. You can relate to this when you fix a bed with different layers of quilts and blankets.
These alternating components constitute layers of hyaline cartilage matrix and dense collagen fibers. They orient a direction that compensates for the pressure on the connective tissue.
It means that its layer arrangement counters the stresses placed on the body organ. This attribute also helps to pad the organs that experience the hardest friction. — vertebrae, knee, long bones.
Does cartilage affect height?
Yes, cartilages can indeed influence the growth of height among people. This event happens when a structure in the bone named growth plate aids in bone elongation. It then points to why children will not stay small and short in their lifetime.
A growth plate is a layer of cartilaginous tissue found in most long bones of the body. Most of the cartilages found in the growth plate belong to the category of hyaline. These hyaline connective tissues provide the growth of bones and soon the height.
The way this tissue affects the height of bones occurs in two ways:
- An embryonic bone will use hyaline connective tissues as its model for growth. They develop through chondrogenesis. The soft hyaline will continue to serve as the temporary bone for the developing body.
- Then as the fetus matures, the hyaline will turn to bones with the help of osteoblasts in the bone matrix. The cartilages digest away and leave a medullary cavity within the bone. By birth, the connective hyaline disappears— except for two structures.
The hyaline undergoes more synthesis and osteoblast action. As this continues, more bones will form and pile up after another. The ending result of this leads to notable growth in bone length. When the bone length increases, the height follows.
Which growth plates determine height?
The epiphyseal plate pertains to the growth plate that determines the height. This hyaline structure can still produce a chondrocyte-producing matrix in the bone. Thus, it can help the long bone achieve longitudinal growth.
The growth plate exists between the epiphyseal and metaphyseal bones. A closer look reveals three zones on the growth plate. These zones contribute to the differentiation of cartilaginous cells helpful for bone formation. They are:
A. Resting Zone
This area has many small chondrocytes that act like stem cells. It also plays a role in protein synthesis and germinal structure maintenance. A slow replication rate happens in this area.
B. Proliferative Zone
This area contains flat chondrocytes lining the long axis of the bone. Production of collagen (Types II and XI) also happens here. The replication rate here speeds up in preparation for bone formation.
C. Hypertrophic Zone
Here, the differentiation of chondrocytes finishes. And you can notice this due to its increased thickness. It also houses a calcified matrix and the formation of bone and vessels. Maturation of bone happens in this zone.
Can HGH make you taller at 18?
No, HGH will not work anymore at the age of 18. Doing so will only cause malfunctions in the Human Growth Hormone levels. Everyone should remember this implication, as it will save their lives.
To put it short, growth in the body and bones stops during adolescence. This time marks the ages of 16-18 years. The growth plate of these ages has now completed its work and converted it into a bone structure.
No chondrogenesis and ossification will happen anymore if this occurs. It is because the plate has already calcified as a spongy bone. All that remains in that area hosts the remnants of the epiphyseal plate. This structure alludes to a bony structure known as the epiphyseal line.
As for the HGH, it cannot play any role anymore in height determination. The bone has now finished its growth. High doses of HGH will only thicken the bone instead of making them increase in length.
HGH now will only work on producing muscle and bone for body organs and cell maintenance. Enlargement of organs and insulin regulation are some actions that HGH can still do now.
Adults that keep supplying HGH in their bodies may sport slight height increases. But these may not even compare to the growth most adolescent children experience. Some may even call this unnatural.
Thus, using HGH to increase height at 18 will not work in most cases.
Is it possible to increase height after 21?
It depends on the development of your bones. If you see that the growth plates on your longs bones still exist, your height can still grow. But there will be no growth with an already-closed growth plate.
For those people with a still-growing growth plate, they still have hope. They can increase their height by also increasing their HGH. This scenario can happen but only in a few cases like delayed growth spurts or a body disorder.
But most cases would have no chance to increase their height when they reach ages 18-21. The growth plates at this point close off.
Still, do not let this discourage you. Eat healthy and nutritious food and strengthen your bones through exercise. You can also wear clothing that would make you appear tall. Positivity in life is one key to looking tall.
What causes cartilage loss?
The cartilages lose their strength when overworked. Friction, mechanical stress, and destructive substances render the connective tissues weak. And in time, the fibers and matrix that hold the cartilaginous mass break down.
There exist many reasons why our cartilages break down. From our body chemistry to the lifestyle we adopt, in particular. All can influence the entire anatomy and physiology of these structures. Here are some causes of cartilage-related loss:
This disorder categorizes as a degenerative disease. So, as you grow older, the cartilaginous fibers in your joints also get old and degrade. They have now worn down because your body has used them ever since.
Sudden traumatic events like injuries or accidents cause weakening in the connective flesh. Atrophy will soon follow in that area, leading to a faster breakdown. These areas should expect easier damage because of their avascularity.
3. Joint Instability
Cartilage-induced damage can cause joints to be loose and movable. It leads to extra motion in the tissue. If they move too much, it can injure that area. Arthritis will soon follow and start degradation of cartilages.
4. Aging and Genes
As mentioned before, aging will weaken the area of concern and reduce the fibers/matrix. Passing faulty genes could also account for the loss of the connective flesh. It happens to a considerable number of people. Even so, both factors induce loss in cartilaginous mass.
5. Lack of Exercise
A sedentary lifestyle will make the joints lose strength. Some cases could also lead to atrophy of joints. Thus, exercises should appear to keep the joints away from under usage.
6. Biomechanics and Poor Alignment
An asymmetrical cartilage loss accounts for joint degradation. You may have a body-alignment issue that is causing certain joints to wear down more than others.
Obesity harms knee joints and increases the load on knee joints by 2-4 times. An increased risk of knee replacement can also happen.
8. Metabolic Disorders
The chemical matrix structure of joints can destabilize by metabolic syndrome. Furthermore, adipose (fat) tissue can overproduce leptin. It is a hormone that regulates a sense of fullness. But it also has an impact on bone and cartilage. Greater leptin leads to more arthritis over time.
9. Poor Nutrition
Poor dietary habits and nutrition deficiency damages your cartilage and musculoskeletal system. What you eat has the power to turn on or off the genes that protect your cartilages.
The drugs injected into arthritic joints for pain treatment also hazards the cartilage. An example of this is epinephrine, which has an acidic (low pH) nature. Apoptosis is the death of cartilage cells caused by anesthetics and steroid medicines.
These only represent a decent number of reasons for cartilage loss. Due to its wide range of disorders, you should be careful of your every action. Your joints and cartilaginous flesh are also important, like your cardiac muscle (heart). (2,219 words)
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