Skeletal System Flashcards
How many bones in Human Body
206
Functions of Skeletal System
- Support Framework.
- Boundaries (skull)
- Attachment for muscles
- Movement (joints)
- Haematopoiesis (in red marrow)
- Mineral homeostasis (calcium & Phosphate)
- Triglyceride storage (yellow bone marrow)
Which part of bone is red marrow found
Spongy bone
Bone Cells
- Osteogenic
- Osteoblasts
- Osteocytes
- Osteoclasts
Osteogenic Cells are:
Bone Stem Cells (undergo division)
Osteoblasts are
Bone building cells
Make & Secrete Collagen & calcium bone matrix
Traps itself in excretion - then it is a osteocyte
Osteocyte
Mature Bone cell
Bone metabolism & nutrient exchange
Osteoclasts
Come from WBC - up to 50 Monocytes (phagocytic)
‘Eating Cells’
Release enzymes & acids that digest bone
Resorption is the breakdown of bone matrix
REMODEL
Compact Bone
Outer Layer- gives strength
formed in cylinders
Haversian canal
Compact Bone - hollow inner part containing nerves, veins, artery.
Lamellae
Rings of extra cellular matrix
Hard matrix extracted by osteoblasts
Canaliculus
Small canal for nutrients to travel
Lacunae
Spaces for Osteocytes
Spongy Bone
- Contains Bone matrix called Trabeculae
- Has no osteons
- The spaces in trabeculae make bone lighter and are filled with BONE MARROW
Where is spongy bone found?
Found in ends of long bone, irregular bones, short, flat & irregular.
Long Bone
greater length than width
Long Bones Heads are called
Epiphyses
Top Epiphyses is called
Proximal Epiphyses
Bottom of Long Bone is called
Distal Epiphyses
Short of Long bone
Diaphysis
Diaphysis contains
Compact bone
Epiphyses contains
Spongy Bone
What is the use of cartilage
Protection - bone on bone movement
Examples of Long Bone
Femur, Tibia, Humerus
Which Hormones promote osteoblast activity
Growth Hormone, Thyroid Hormone, Oestrogen & testosterone, Calcitonin
Which Hormones promote Osteoclast activity
Parathyroid Hormone, Cortisol
Calcitonin affect on bones
Takes calcium from blood into bone
