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Human Rib Cage

RELATED WORDS

  • Radical
  • Primary root
  • Secondary root
  • Lateral root
  • Adventitious roots
  • Fibrous root system

Definition of Human Rib Cage

A protective structure in the chest region formed by the vertebral column, ribs, coastal cartilages and sternum

More About Human Rib Cage

  • The rib cage is also known as thoracic cage or the thoracic basket
  • It is more or less triangular and conical in shape
  • Its main function is protection of the heart and lungs in the chest area and upper abdomen
  • It supports the skeletal frame work of the body
  • Also, the rib cage plays a vital role in the breathing mechanism, as it can expand and contract with the help of respiratory muscles and diaphragm
  • The lower end of the rib cage is attached to the diaphragm
  • The bones that form the rib cage are
    • Sternum - a flat and dagger shaped bone, made up of three bones namely manubrium, body and xiphoid process. It is approximately 15cm long situated on the midline of thorax
    • It is longer in males than in female
    • Thoracic vertebrae - they are 12 in number and are attached to the ribs from the dorsal side
    • Ribs –They are “C” shaped bones joining the sternum on the ventral side and the thoracic vertebra on the dorsal side
    • There are 24 ribs, 12 on either side of the sternum and vertebrae
    • The ribs from 1-7 are attached to the sternum by coastal cartilage and hence are known as “true ribs”
    • The 8th, 9th and 10th ribs are not attached directly to the sternum but are attached to the coastal cartilage of the 7th rib, and hence are known as “false ribs”
    • The 11th and 12th ribs are attached to the vertebrae but not to the sternum and hence are known as “floating ribs”. They protect the kidneys

Questions related to Human Rib Cage:

1) Which among the following pairs are known as “false ribs”

    a) 1st -7th
    b) 7th - 10th
    c) 8th – 10th
    d) 11th and 12th

Solution: (c) The ribs from 8th to 10th are not attached directly to the sternum but to the coastal cartilage of the 7th rib and hence are known as false ribs

2) How many ribs together are involved in the formation of rib cage?

    a) 22
    b) 24
    c) 12
    d) 28

Solution: (b) 24 ribs are involved in the formation of rib cage, 12 on either side of the sternum and vertebrae

3) What is the function of the coastal cartilage in the rib cage?

Solution: The coastal cartilage connects the ribs from 1-7 to the sternum

4) What are floating ribs?

The 11th and 12th ribs of the rib cage are not attached to the sternum, but are attached to vertebrae only . These ribs are known as floating ribs