The jawbone, also referred to as the mandible, is the only bone that is not present at birth. It develops during the late stages of fetal development. The mandible is formed from several pairs of cartilage bones that eventually fuse together during childhood.
The two halves of the mandible, or the left and right ramus, are initially the first bones to develop. They gradually flatten and spread out, forming the shape of the mandible. As the mandible grows during the later stages of fetal development, the cartilage bones continue to elongate and ossify (harden) to form the adult jawbone.
Although the mandible is not present at birth, it is completely developed by the time of birth and is visible on radiological studies.
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What bones are babies born with?
Babies are born with many bones and cartilage present. At birth, babies have around 300 bones, almost double the amount of 206 adult bones, due to their temporary bones, which later fuse together and form a single bone.
The 300 bones include the skulls, which is made up of 28 bones and several cartilage pieces. Other bones present at birth are the collarbone, shoulder Blades, Elbow Bones, Wrist Bones, Pelvis, Leg Bones, as well as the toe bones.
Babies also have 6 digits on their hands and feet and cartilages, which form the baby’s ribcage. As babies grow and mature, the temporary bones fuse and the number of bones decreases. By adulthood, the bones typically fuse and the total number of bones is commonly 206.
Why are babies not born with kneecaps?
Babies are born without kneecaps, otherwise known as patellae, because the bones and muscles supporting them are not fully developed yet. Although human fetuses do form rudimentary kneecaps at about 12 weeks gestation, the patellae gradually ossify and fully form during the last trimester of pregnancy and during the early weeks of a baby’s life.
During this time, babies’ bodies are rapidly growing and developing and their patellae are still forming and strengthening. Without this extra time of development, babies’ knees wouldn’t have the support they need to bear their weight or to function the way they are meant to.
Furthermore, without fully developed and functional kneecaps, babies’ knee joints would lack stability and be prone to dislocations and other problems. As babies become toddlers, their muscles, ligaments, and other supporting structures around the knee become strong enough to support their weight and the kneecaps can then harden and become more functional.
Are we all born with blue eyes?
No, we are not all born with blue eyes. Eye color is determined by the several genes inherited from both parents. All babies are born with some degree of melanin in their eyes, which is the pigment that gives brown eyes their color.
Brown eyes are the most common eye color in the world, present in over 55% of the population. Other eye colors such as blue, green, and hazel, are a result of low levels of melanin. In some cases, babies can be born with eyes of two different colors, a result of one eye having high levels of melanin and the other having low levels.
However, it is very rare for newborn babies to have blue eyes and if they do, their eye color may change as they get older.
Is it true that 80% of babies have some type of birthmark?
No, it is not true that 80% of babies have some type of birthmark. According to studies conducted by the Journal of Pediatrics, only approximately 10-15 percent of babies are born with some type of birthmark.
Of those babies, approximately 5-10 percent have a birthmark that is visible at birth. The most common type of birthmark is the vascular or “stork bite,” which can vary in size and color and appear anywhere, but is typically found on the forehead, eyelids, neck, and upper back.
Other birthmarks, such as moles and port wine stains, occur less often. While the cause of birthmarks is still largely unknown, it is believed to be related to genetics, environment, and the mother’s health during pregnancy.
Why are babies bones not fused?
Babies’ bones are not fused because it allows them to grow and develop normally. Bones are formed from cartilage in a process called ossification, which involves the bones becoming harder and taking on their final shape.
In babies, it is necessary for some bones to remain unfused in order to allow for growth as new bones are formed and replace cartilage. Eventually, all bones, including those in the baby’s limbs, will fuse together, but this process doesn’t begin until the child is several years old.
During infancy, the unfused bones provide an important base of flexibility and mobility which is helpful for learning to crawl, walk and develop the muscles in their limbs. Without unfused bones, their mobility and range of motion would be limited.
Unfused bones also allow the muscles and tendons to develop at a normal rate and help to prevent fractures as the child learns how to move and coordinate their movements. The unfused bones provide a sense of security for parents and a framework for healthy development during infancy.
What happens if you don’t have a kneecap?
If you don’t have a kneecap, also known as patella, it can result in instability in the knee joint and affect the movement of the lower limbs. Although it is extremely rare, it is possible to be born without a kneecap due to a condition known as congenital patellar aplasia.
Without a kneecap, the knee joint can become much more prone to instability and to injuries that would normally not occur with a normal kneecap. Without the support from which a kneecap normally provides, most people experience knee hyperextension, swelling and pain.
Without the kneecap, bones of the lower leg can move, grind, and rub against each other which causes a great deal of pain, as well as difficulty in walking. Depending on the severity of the condition, medical treatment may be necessary to improve stability and decrease the risk of injuries.
This can include knee bracing, physical therapy, and, in extreme cases, surgery.
Can you walk without a kneecap?
No, you cannot walk without a kneecap. Your kneecap (also known as the patella) is an important component of the knee joint and allows for the bending, straightening, and stability of the knee. Without a kneecap, you would have difficulty walking, as the kneecap is crucial for bearing your body weight while stationary and while walking.
People who have damaged or missing kneecaps may require a special knee brace to help stabilize the knee joint as they walk and perform other activities. A surgically implanted titanium artificial kneecap can also be used to replace a missing or damaged kneecap, allowing individuals to walk properly again.
What age can a baby smile?
The age when a baby can first smile varies from baby to baby and can happen as early as two to three weeks old or as late as two to three months old. A baby’s first smile usually happens when the baby is alone and usually in response to a sound or physical stimulation.
That initial smile is usually fleeting and brief, but with time and responded to with love and care, a baby will usually start to smile intentionally at faces and with more frequency. As a baby gets older, smiles become increasingly common as he or she begins to develop socialization skills and recognize familiar faces.
Smiling is an important developmental milestone and important part of baby’s journey in learning to communicate.
