Yogy's biology

  08 Respiration and Circulation - part 01 - Organs of respiratory Exchange Introduction : All living organisms require energy to carry out various  life processes.  The energy that is stored in the body in the form of  complex organic compounds  (potential energy) This energy is not usable by the organisms unless  it is converted into usable form . This conversion is achieved through the  process of respiration. Respiration  : Biochemical process of  oxidation of organic compounds  in an orderly manner for the liberation of chemical energy in the form of  ATP. For this, the process of  gaseous exchange  takes place between the organism and the environment.  The site of gaseous exchange :  respiratory surface Organs of respiratory Exchange : Respiratory exchange is a simple physical process.  For efficient gaseous exchange, the respiratory surface should have the following features : It should have a large surface area. It should be thin, highly vascular and permeable to allow exchange

  16. Skeleton and Movements - part 05 - Appendicular skeleton and Disorders related to muscles B. Appendicular skeleton :  Appendicular skeleton consists of bones of limbs and girdles. Pectoral girdle :  Shoulder girdle It attaches forelimb skeleton with axial skeleton. There are  two  pectoral girdles, each consists of a shoulder blade or  scapula  and  collar bone or clavicle. Clavicle :  It is  ‘s’ shaped  slender bone.  One end of clavicle is attached to acromion process of scapula.  The other rounded end called  sternal end  attaches to manubrium of sternum. This connects upper arm skeleton to axial skeleton. Scapula :  It is a large, flat, triangular bone that  occupies posterior chest wall  extending from second to seventh ribs.  It is attached to axial skeleton by muscles and tendons.  At it’s lateral angle, scapula bears a concave socket called  glenoid cavity.  Head of humerus (the upper arm bone) fits into the glenoid cavity.  Two processes arise from scapula, a beak like 

  16. Skeleton and Movements - part 04 - Skeletal System Skeletal System : Multicellular animals need support to maintain body structure.   Skeletal structures When present on outer surface of the body are called  exoskeleton. Skeletal structures When present on inside  the body are called  endoskeleton . Bones and cartilage  form major endoskeletal components.  Exoskeletal components include chitinous structures,  nails, horns, hooves, scales, hair, etc; Our skeletal system is made up of cartilage and bone; which together form the framework of the body.  Cartilage is slightly pliable while bones have hard matrix.  Bones form the framework of our body and thus provide shape which giveus our identity.  They protect delicate organs. Joints between bones help in  movement and locomotion.  Bones provide firm surface for attachment of muscles.  They are reservoirs of  calcium  and one important site for haemopoiesis. Endoskeleton of an adult human consists of  206 bones  which can be groupe