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       Some important facts about Human body

 

  • There are nine organ system-    Skeleton systemMuscular,  systemNervous system, Circulatory system , Respiratory system, Excretory system, Reproductive system, and Endocrine system .                                           

Skeleton System


  •   There are two type of skeleton system-                                                                                                                                                                            
  1. Exo skeleton
  1. Edo skeleton
  •   Exo skeleton- They are made up of skin
  •   Endo skeleton- They are made up of bone and cartilages
  •   Frog has not found any endo skeleton.
  •   Human has endo skeleton like-hair and nails
  •   Bird has endo skeleton like- feather, beak or
  •  Animal has endo skeleton like – horn, hoof or hair
  •   Snake, Fish and lizard have endo skeleton like- scales
  •   Colour of skin because of melanin.
  •   Work of melanin – protect from sunlight
  •   Protein found in our body is called Keratin.
  •   Cartilage is always in the state of hotness.
  •   There are no cartilages are present in shark fish.
  •   Most of cartilages convert into bones.
  •   Nasal septum and ear pinna are away from cartilage body.
  •   Cartilages are found at the end of the bone.
  •   No. of bones in adult is 206 and in child is 276.
  •   Largest bone of body is Femur.
  •   Strongest bone of body is Jaw bone.
  •   Smallest bone of body is Ear bone.
  •   Skeleton divided into two parts –     
  1.   Axial skeleton
  2.   Appendicular skeleton

 

 

  • Axial skeleton is divided into five parts –

1.       Skull

2.       Backbone

3.       Ribs

4.       Sternum

5.       Ear bone

  •   Appendicular is divided into three parts –

1.       Hand

2.       Legs

3.       Girdles

 

                   Skull

The cranium (skull) is the skeletal structure of the head that supports the face and protects the brain. It is subdivided into the facial bones and the brain case, or cranial vault . The facial bones underlie the facial structures, form the nasal cavity, enclose the eyeballs, and support the teeth of the upper and lower jaws. The rounded brain case surrounds and protects the brain and houses the middle and inner ear structures.

 

 

  •   Skull (29 bones ) is divided into three parts –

1.       Face (14 bones )

2.       Cranium (8 bones )

3.       Ear (6 bones )

 

          Face (14 bones )

            

                  

1.       Lacrimal (2 bones )

2.       Nasal ( 2 bones )

 


                Ear

        

The ear is made up of three parts: the outer, middle, and inner ear. All three parts of the ear are important for detecting sound by working together to move sound from the outer part through the middle and into the inner part of the ear. Ears also help to maintain balance.

  •  Ear drum is also known as Tympani membrane.
  •   Study of ear – Otology
  •   Ear provides balance to the body.
  •   Endolymph is found in internal ear.
  •   Ear has three parts –

1.       External ( ear pinna )

2.       Middle ear

3.       Internal ear (endolymph)

 

The Outer Ear

 

  •   The outer ear includes:

 

1.       auricle (cartilage covered by skin placed on opposite sides of the head)

2.       auditory canal (also called the ear canal)

3.       eardrum outer layer (also called the tympanic membrane)

 

  • The outer part of the ear collects sound. Sound travels through the auricle and the auditory canal, a short tube that ends at the eardrum.

The Middle Ear

 

  •   The middle ear includes:

 

1.       eardrum

2.       cavity (also called the tympanic cavity)

3.       ossicles (3 tiny bones that are attached)

·         malleus (or hammer) - long handle attached to the eardrum

·         incus (or anvil) - the bridge bone between the malleus and the stapes

·         stapes (or stirrup) - the footplate; the smallest bone in the body

 

The Inner Ear

 

  •   The inner ear includes:

 

1.       oval window - connects the middle ear with the inner ear

2.       semicircular ducts - filled with fluid; attached to cochlea and nerves; send information on balance and head position to the brain

3.       cochlea - spiral-shaped organ of hearing; transforms sound into signals that get sent to the brain

4.       auditory tube - drains fluid from the middle ear into the throat behind the nose

 

Back bone / vertebrae 


  •   The spine is made up of bones, muscles, tendon,  nerves and other tissues that reach from the base of the skull near the spinal cord (clivus ) to the coccyx  (tailbone) .
  •   The  vertebrae of the spine include the cervical spine ( C1 – C7 ), thoracic spine ( T1 – T12 ), lumber spinal (L1 – L5 ), sacral spine (S1 – S5 ) and the tailbone.
  •   The spinal cord is divided into segments, each containing a pair of spinal nerves that send messages between the brain and the rest of the body.
  •   There are 33 cervical spine in child .
  •   There are 26 cervical spine in adult.
  •   Cervical spine has two bone –

1.       Atlas

2.       Axias

  •   The  collar bone, or clavicle bone or wish bone , is a long and thin bone that runs between the sternum and shoulder blade.

 

Hand  


  • There are 30 bone in one hand and total bones in both hand is 60.
  •  Upper arm has humerus  bone.
  •  Lower arm has radius and ulna bone.
  •  Wrist has carpel bone ( 8 bone ).
  •  Palm has meta carpel bones ( 5 bones ).
  •  Finger of hand has phalanges  bone ( 14 bones ).

 

Legs

  •   There are 30 bones in leg and total bones in both legs are 60.
  •   Upper bone of leg is femur ( largest and powerful bone ).
  •   Lower bone of leg is tibia and fibula .
  •   Ankle bone of leg is tarsal bone.
  •   Sole has metatarsal bone.
  •   Finger of legs has phalanges bone.
  •   The Patella, also known as the kneecap, is a flat, circular – triangular bone which articulates with the femur and covers and protects the anterior articular surface of the knee joint.

 

Girdles


  •   Girdle are two types -

 

1.       Pectoral girdle

 

Your body is comprised of joints, muscles, and structures that connect one bone to the next. A pectoral girdle, also referred to as the shoulder girdle, connects your upper limbs to the bones along the axis of your body. You have two pectoral girdles in your body.

 

The pectoral girdle consists of the two bones that make up your shoulder:

 

·         clavicle, or collarbone

·         scapula, or shoulder blade

 

Your pectoral girdles are responsible for providing structural support to your shoulder region on the left and right side of your body.

 

The pectoral girdles on either side of your body aren’t joined together. This allows for your shoulder and arms to move and function independently.

The pectoral girdle is made up of two major bones: the clavicle and scapula.

 

2.       Pelvic Girdle

               It is subdivided into the pelvic girdle and the pelvic spine. The pelvic girdle is composed of the appendicular hip bones –

·         Ilium

·         Ischium

·         Pubis

The pelvic spine consist of the sacrum and coccyx.

              Ribs

 

  •   The ribs are a se of 12 bones which form the protective ‘cage’ of the thorex.
  •   They articulate with the vertebral column posteriorly ,and terminate anteriorly as cartilage.
  •   As part of the bony thorex, the ribs protect the internal thoracic organs.

 

Sternum

  •  Sternum bone or breastbone is a long flat bone located in the central part of the chest.
  •  It connect to the ribs via cartilage and forms the front of the rib cage .
  • It helping to protect the heart, lungs, and major blood vessels from injury.