Body Movement/ Skeleton System/ Joints/ Their types & Defination

Body Movement 

 Topics

    1- Cilia 

    2- Pseudopodia 

    3- Flagella

    4- Muscles

Skeleton System 

   Topics

        1- Axial 

        2- Appendicular

        3- Joints

 

Body Movement

         One of the important distinguishing features of living beings is movement. Movement can be observed in both plant and animals. Set of movement that result in change in position is called locomotion. Animals move usually for food, shelter, mating, etc., and the methods of locomotion depend upon their habitat and the demand of situation. 

 

There are different kinds that help in movement, such as cilia, flagella, Pseudopodia and muscles. 

1- Cilia 

       Cilia minute hair- like organelles in eukaryotic cells. Ciliary movement can be observed in protozoans like  𝙥𝙖𝙧𝙖𝙢𝙚𝙘𝙞𝙪𝙢 and also in most of our internal organ that are lined by ciliated epithelium. 

For example, the coordinated movement of cilia in respiratory tract that helps us in removing dust particle and foreign materials inhaled along with the atmospheric air. 

2- Pseudopodia

           Pseudopodia are temporary projections of plasma membrane seen in eukaryotes. Cells that show pseudopodia that are usually referred to as Amoeboids. Some blood cells in our body (leucocytes) exhibit amoeboid movement. The unicellular protozoan, amoeba perform various activities by the formation of pseudopodia. 

3- Flagella

       Flagella are lash-like appendages that protrude from prokaryotic and Eukaryotic cells. Mammalian sperm cell is an  example Eukaryotic cell bearing flagella. Sperm cell uses its flagellum to travel through the female reproductive tract.

4- Muscles

       Muscles are specialized tissue that contract and relax to cause movement. Muscles are of three types skeleton, smooth and cardiac muscles. There are over 600 muscles in our body. 

   Skeleton muscles attach to bones at various locomotion and aid in movement. The contraction and  relaxation with the help of two protein actin and myosin. 

Skeleton System  

     Skeleton system comprises a framework of bones and few cartilage. Human body (adult) comprises 206 bones and the skeleton is divided in two. 

    1- Axial Skeleton

    2- Appendicular

1- Axial Skeleton

        It consists of 80 bones that are distributed along the main axis of the body. Axial skeleton includes

 • Skull- Hard, protective skeleton of head.

 • Sternum - Flat bound in the centre of chest

 • Ribs - Long, curved bones which form the ribcage. 

 • Vertebral column - Extends from base of the skull and protect the spinal cord. 

2- Appendicular

       It support the appendages, for example, limbs. In human body, each limb is made up of 30 bones of hands are :

     • Humerus

     • Radius

     • Ulna

     • Carpals (wrist bones) 

     • Metacarpals ( palm bones) 

     • Phalanges (digits)

The bones of lower limbs are:

     • Femur ( thigh bone) 

     • Patella

     • Tibia

     • Fibula

     • Tarsals

     • Metatarsals

     • Phalanges

Joints 

    A joint is the area where two bones are attached for the purpose of permitting movement of body parts. They are essential for  all types of movement. 

There are three types of joint

  

  1- Fibrous Joints- Do not allow movement, for example, joints between skull bones. 

 2-Cartilaginous Joints- Permit limited movement, for example, joints in vertebral column. 

 3- Synovial Joints- Allow considerable movement. Contain a fluid- filled cavity called synovial cavity, for example, knee joint. 

Set of movement that change in position is called locomotion

  

 

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