THE SKELETAL SYSTEM
The human Skeletal System is the bony framework of the body. it forms cavities and fossa e that protect some structures forms the joints and give attachment to muscles. The skeleton parts are described in two parts axial and appendicular. The appendicular skeleton attached to the axial Skeleton. skeletal system anatomy notes pdf. This is “human body bone names”. The axial skeleton consists of the skull, vertebral column, sternum, and ribs. the axial skeleton protects major vital organs and in the axial skeleton having a total of 80 bones.
The skull described in two parts, the cranium which contains the brain, and the face. it consists of a number of bones, develops separately but fuses together as they mature. in the skull bones, only one movable bone is the mandible or lower jaw. The Names of the skull bones (human body bone names) are :
The cranium is formed by a number of flat and irregular bones that provide bony protection for the brain. It has a base upon which the brain rests and a vault that surrounds and covers it. The peritoneum lining the inner surface of the skull bones forms the outer layer of the dura mater. In the mature skull, the joints between the bones are immovable. The bones of the cranium are –
- Frontal Bone – 1
- Parietal Bone – 2
- Temporal Bone – 2
- Occipital Bone – 1
- Sphenoid Bone – 1
- Ethmoid Bone – 1
The skeleton of the face is formed by 13 bones. The bones of the face are –
- Zygomatic Bone (cheekbone) – 2
- Maxilla Bone – 1
- Nasal Bone – 2
- Lacrimal Bone – 2
- Vomer Bone – 1
- Palatine Bone – 2
- Inferior conchae – 2
- Mandible Bone – 1
Some Other Bones –
- Hyoid bone (1) – It does not articulate with any other bone but is attached to the styloid process of the temporal bone by ligaments.
- Auditory Ossicles – Malleus bone (2), Incus bone (2), Stapes bone (2). Stapes is the smallest bone in the human body.
Functions of the Skull / Skeletal System functions
The various part of the skull have specific and different functions –
- protection of delicate structures including the brain, eyes, and inner ears
- maintaining patency of the nasal passages enabling breathing
- eating – the teeth are embedded in the mandible and maxilla; and movement of the mandible, the only movable skull bone, allows chewing. This is a brief knowledge of the functions of the skull in pdf.
This consists of 24 movable bones (vertebrae) plus the sacrum and coccyx. The bodies of the bones are separated from each other by intervertebral discs, consisting of cartilage. The vertebral column is described in five parts and the bones of each part are numbered from above downwards
- Cervical – 7
- Thoracic – 12
- Lumbar – 5
- Sacrum – 1 (5 fused bones)
- Coccyx – 1 (4 fused bones)
Functions of The Vertebral Column / Skeletal System functions
The Vertebral Column has several important functions
- It protects the spinal cord. In each vertebra is a hole, the vertebral foramen, and collectively the foramina form a canal in which the spinal cord lies.
- Adjacent vertebrae form openings, which protects the spinal nerves as they pass from the spinal cord
- In the thoracic region the ribs articulate with the vertebrae forming joints allowing movement of the ribcage during respiration.
The thoracic cage is formed by
- Sternum or breast bone – 1
- Ribs – 12 pairs
- Thoracic vertebrae – 12
Functions of the thoracic cage
- It protects the thoracic organs including the heart, lungs, and large blood vessels.
- It forms joints between the upper limbs and the axial skeleton. The upper part of the sternum, the only joints between the upper limbs and the axial skeleton.
- It gives attachment to the muscles of respiration.
The appendicular skeleton consists of the shoulder girdles and upper limbs, and the pelvic girdle and lower limbs. human body bone names pdf.
The shoulder girdles and upper limbs.
Each shoulder girdle consists of a clavicle and scapula. Each upper limb comprises:
- Humerus – 1
- Radius – 1
- Ulna – 1
- Carpal Bones – 8
- Metacarpal bones – 5
- Phalanges – 14
The pelvic girdle and lower limbs.
The bones of the pelvic girdle are the two innominate bones and the sacrum. Each lower limb consists of –
- Femur – 1
- Tibia – 1
- Fibula -1
- Patella -1
- Tarsal bones – 7
- Metatarsal bones -5
- Phalanges -14
Functions of the Appendicular skeleton / Skeletal System functions
The appendicular skeleton has two main functions –
- Voluntary movement – The bones, muscles, and joints of the limbs are involved in movement of the skeleton. This ranges from very fine finger movements needed for writing to the coordinated movement of all the limbs associated with running and jumping.
- Protection of delicate structures – Blood vessels and nerves lie along the length of bones of the limbs and are protected from injury by the associated muscles and skin. These structures are most vulnerable where they cross joints and where bones can be felt immediately below the skin.
The medical term is the absence of menstrual period (bleeding) in a woman of reproductive age is known as amenorrhea or menostasis. There are two types of amenorrhea Primary & Secondary amenorrhea.
Primary amenorrhea – in the presence of normal growth and secondary sexual characteristics the young woman has not had her first period by the age of 16.
Secondary amenorrhea -This is when a woman who has had regular periods stops having her period for a minimum of 90 days or three months or longer. caused by Pregnancy, Breastfeeding, Menopause, Some birth control methods, Hormonal imbalance, Poor nutrition, Depression and Certain prescription drugs, etc.
Cryptomenorrhea or cryptomenorrhoea is one of the most serious conditions also known as hematocolpos. An abnormal condition in which the products of menstruation are retained within the vagina because of an imperforate hymen. Menstruation occurs but does not appear due to opposition to the outflow tract. Cryptomenorrhea may look like they are amenorrhea. Amenorrhea and Cryptomenorrhea involve no visible menstrual fluid. In the cryptomenorrhea, you will likely experience cyclical menstrual pain like cramping, Premenstrual Syndrome and tender breasts, etc. In amenorrhea, there is no menstruation for some reason.
Transfer of disease from one organ or part of the body to another not, directly connected with it, due either to transfer of cells, All malignant tumors are capable of metastasizing.
Excessive ingestion of food, not from hunger but due to loss of the sensation of satiety.
Congenital absence of the heart.
Expulsion from the uterus of the product of conception before the fetus is viable. this is the premature arrest of a natural or morbid process.
In a mature Morgagnian cataract, the cortex is completely liquefied and the nucleus rotates freely within the lens.