AN120: Lesson 3 Flashcards
(122 cards)
The 4 Functions of the human skeleton
- Body Support
- Protection
- Motion
- Formation of blood cells (hematopoiesis)
How does the skeleton support the body?
It provides a framework for the human body
What is an example of the skeleton protecting soft structures?
The skull which surrounds the brain
How do bones allow for motion?
Muscles are attached to them and moves them. The bones are what provide leverage for motion.
Where does hematopoieses occur?
In red bone marrow, mainly in flat bones.
What organs do the ribcage and sternum protect?
They protect the thoracic cavity’s viscera as well as the upper abodominal viscera
Define Bone
A hard connective tissue that consists of cells, fibres, and matrix.
What makes bone hard?
Calcification of its ECM
What makes bone have a degree of elasticity?
The organic fibres.
2 Forms of Bone:
with definition
- Compact bone (appears as a solid mass)
- Cancellous bone (spongy appearance)
What are trabeculae?
and their function
Trabeculae are the branching networks that gives cancellous bone resistance against mechanical stresses and strains
Which cell breaks down old bone tissue
Osteoclasts
Which cell forms new bone tissue?
osteoblasts
Important to note
What are bones composed of?
- an exterior cortex
- an interior network, filled with blood vessels and marrow
Define osteoclast
Break down old bone tissue to make room for new, healthier tissue to replace it.
What are the structural levels of bone?
- Cortex
- Medulla
- Marrow
Define osteocytes
Cells responsible for maintaining bone growth and density
What is the outer layer of bone?
Cortex
Define Cortex
Outer layer of bone made up of compact/dense bone tissue and is covered with periosteum.
What is the inner portion of bone?
Medulla
Define Medulla
Inner portion of the bone that consists of cancellous/ spongy bone tissue.
What is unique about the medulla in some bones?
and in which bones
Particularly in long bone, the medulla has a hollow space with no bone tissue.
- It is called the medullary/ marrow cavity.
Define Marrow
Serves as a filler inside of bones
Types of Marrow
- Yellow
- Red