MUSCULOSKELETAL SYSTEM [CSEC HSB & BIOLOGY]

-

SYLLABUS REFERENCE 

CSEC HSB 

  • [B4.1] identify the major bones of the skeleton; 
  • [B4.2] relate the structure of the skeleton to its functions; 
  • [B4.7] identify a hinge joint, fixed joint, and ball-and-socket joint; 
  • [B4.9] identify the biceps and triceps of the upper arm; 
  • [B4.10] explain how skeletal muscles function in the movement of a limb; 
  • [B4.11] explain the importance of locomotion to man. 

CSEC Biology 

  • [B6.2] relate the structure of the skeleton to its function in humans;
  • [B6.3] discuss the importance of locomotion in animals; 
  • [B6.4] describe the mechanism of movement in a human forelimb.  

IMPORTANCE OF LOCOMOTION TO HUMANS 

Locomotion is the ability to more the entire individual from one place to another independently. 

This ability is very important to our independence and identity. 

Generally, locomotion is required:

  • for defence 
  • to search for food and shelter 
  • to care for young ones 
  • to work 
It is also a major aspect of our socialisation and community building. 

COMPONENTS OF THE MUSCULOSKELETAL SYSTEM 

The Skeleton 

The skeleton has a basic framework that consists of the following:

  • Axial Skeleton 
  • Appendicular Skeleton 


Types of Joints




At CSEC level, the focus is on the following types of joints... 

Hinge 

Fixed 

Ball-and-Socket 

Both hinge and ball-and-socket joints are SYNOVIAL JOINTS. 




Functions of the Skeleton 

Movement

Bones act as points of attachment for the skeletal muscles. The skeleton acts as a system of levers, powered by muscular contraction. 



Protection

  • The cranium protects the brain, eyes, and ear canal.
  • The rib cage protects the lungs and heart. 
  • The vertebral column protects the spinal cord. 
  • The pelvis protects the uterus (womb). 

Support

The skeleton acts as a framework (or scaffolding) for the rest of the organ systems of the body. 

The backbone supports the limbs and head. The jawbones support the teeth. 

Breathing

The intercostal muscles move the rib cage up and down, in and out, in order to facilitate breathing. 

This movement increases and decreases the volume of the thoracic cavity, causing air to move in and out of the lungs. 



Production of Red Blood Cells

Red bone marrow, found on the inside of short bones and at the ends of long bones such as the humerus, have stem cells. 


These special cells divide by mitosis to produce red blood cells, thus continuously replacing the older cells. 


Important Comparisons






MECHANICS OF MOVEMENT 

Using Biceps and Triceps as an Example:
  • Muscles can only contract. 
  • The bones act as levers and points of attachment. 
  • Each arrangement consists of two or more bones, plus muscles are arranged to pull the bone in opposite directions. These are called antagonistic muscles. 








Popular posts from this blog

HUMAN REPRODUCTION [CSEC HSB & BIOLOGY]

-
Image
SYLLABUS REFERENCE  CSEC BIOLOGY  [B9.2] describe the structure & function of the reproductive systems in humans;  [B9.3] describe the menstrual cycle;  [B9.4] outline the mechanism for bringing gametes together, their fusion, and the development of the embryo in humans;  CSEC HSB [B7.2] describe the structure and function of the reproductive systems in human beings;  [B7.3] describe the menstrual cycle;  [B7.4] explain ovulation, fertilisation, implantation, and development of the embryo;  [B7.5] describe the stages of the birth process; 
Read more

RESPIRATION, GASEOUS EXCHANGE, AND BREATHING [CSEC BIOLOGY & HSB]

-
Image
SYLLABUS REFERENCE  CSEC HSB  [B2.1] explain the importance of breathing in humans;  [B2.2] relate the structures of the respiratory tract to their functions;  [B2.3] describe the breathing mechanism;  [B2.6] distinguish between gaseous exchange and breathing;  [B2.7] identify characteristics common to gaseous exchange surfaces;  [B2.8] differentiate between aerobic and anaerobic respiration;  CSEC BIOLOGY  [B3.1] describe the process of aerobic respiration; [B3.2] distinguish between aerobic and anaerobic respiration;  [B3.3] describe the mechanism of breathing in humans and gaseous exchange in flowering plants;  [B3.4] identify characteristics common to gaseous exchange surfaces; 
Read more

NERVOUS vs ENDOCRINE SYSTEM [CSEC HSB & Biology]

-
Image
SYLLABUS REFERENCE  CSEC HSB [B6.1] describe the main divisions of the nervous system;  [B6.2] distinguish between a neuron and a nerve;  [B6.3] explain the functions of motor and sensory neurons and spinal synapses;  [B6.4] describe the functions of the parts of the brain;  [B6.5] describe the mechanisms of a reflex action;  [B6.6] explain the process by which voluntary actions occur;  [B6.7] distinguish between a voluntary and involuntary action;  [B6.8] explain the response of the sense organs to stimuli;  [B6.13] compare and contrast endocrine and nervous control systems;   [B6.14] identify the sites of hormone production;   [B6.15] explain the roles of selected hormones in the human body;  CSEC Biology  [B7.1] define 'stimulus' and 'response';  [B7.2] describe the response of: (a) green plants to stimuli; (b) invertebrates to variations in light intensity, temperature and moisture;  [B7.3] define receptor and effector;  [B7.4] explain why the response to stimuli is
Read more