Chapter 7 - Anatomy Flashcards
What are the two parts that make up the skeletal system?
Axial and appendicular.
(T/F) The axial skeleton consists of the upper and lower extremities.
False. The axial skeleton consists of the head, neck and trunk.
What are the two most important functions of the skeletal system?
Leverage and support.
What is a lever arm?
A lever arm is the distance from the axis or fulcrum to the point at which a force is applied to the lever.
What is a fulcrum?
The pivot point of a lever.
Name the three types of lever systems:
First class. Second class. Third class.
What is the most rigid connective tissue found in the human body?
Bone.
What is trabeculae?
Plates of calcified tissue that make up the innermost layer of bone.
What is the strong fibrous membrane that offers strength and stiffness to the skeleton?
Periosteum.
Give examples of a long bone:
Humerus, radius, ulna, femur, fibula, tibia, metatarsals, metacarpals, phalanges.
Give examples of flat bones:
Ribs, ilium, sternum, scapula.
What are irregular bones?
The bones found in the skull, pelvis, vertebrae and consist of spongy bone with thin compact bone on the exterior.
What is Wolff’s Law?
A theory developed by the German anatomist and surgeon Julius Wolff (1836–1902) in the 19th century that states that bone in a healthy person or animal will adapt to the loads under which it is placed.
(T/F) One of the benefits of exercise is that it helps increase bone mass.
True.
(T/F) The two categories of joints are synarthroses (non-synovial joints) and diarthroses (synovial joints).
True.
The cartilaginous joints are made of what cartilage?
Fibrocartilage or hyaline growth cartilage.
(T/F) In diarthrodial (synovial) joints, the end of the bones are free to move in relation to one another.
True.
All synovial joints have what five characteristics?
(1) articular cartilage, (2) joint cavity, (3) articular (fibrous) capsule, (4) synovial membrane and (5) synovial fluid.
What are proximal joints? Give examples:
Are the most proximal and the foundation for the extremities (shoulder/hip). These joints generally have the greatest freedom of movement and have a great deal of muscular support in fan-shaped arrangements.
What are distal joints? Give examples:
Complex in structure (wrist, ankle) with a variety of motions available with intricate control.
Define the term agonist. Give an example:
A muscle that is most effective in causing a certain joint movement. Biceps brachii in a biceps curl.
What opposes the agonist?
Antagonist.
What is a synergist? Give an example:
A synergist is when two muscles have a common joint action but also have a joint action that opposes each other. The synergy occurs during the common joint action. Example: Pectoralis major and latissimus dorsi during internal rotation of the humerus.
(T/F) A stabilizer is a muscle or set of muscles that steady or support a joint so another muscle or sets of muscles may move a portion of the body.
True.
