Most bones formed by intramembranous ossification are the long, short, and irregular bones. T or F
Epiphysis usually remain cartilage through birth. Ossification of these epiphyses________
is produced by secondary ossification centers
For intramembranous ossification to take place, which of the following in necessary?
an ossification center forms in the fibrous connective tissue
Steps of intramembranous ossification:
1. Oss. centers appear
2. Osteoblasts secrete osteoid, then calcifies
3. Woven bone and periosteum form
4. Lamellar bone replaces woven bone
Bones are constantly undergoing resorption for various reasons. Which of the following cells acomplishes this process?
During prenatal development, most bones beneath the skull form by a process known as ________
Which of the following is NOT a step in intramembranous ossification?
Destroy and remove old cartilage
_____begins around week 8 of development and continues until a person stops growing?
Growth in the length of long bones during infancy and youth is through ___
Interstitial growth (longitudinal) of the epiphysial plates
Which of the following concerning bone remodeling is not true?
All true! (most adult bone changes, occurs between periosteum and bone, occurs between endosteum and bone, occurs in osteogenic layer)
12th week of endochondral ossification, cavity consisting on nutrient artery/vein, nerve fibers, red marrow, osteoblasts, and osteoclasts
Stages of a healing bone fracture:
2. Fibro. cartilage callus formation
3. Bony callus
4. Bone remodeling
The ammount of movement permitted in a particular joint is the basis for the structural classification of joints. T or F
False - Functional classificaion
Conn. tissue sacs lined with synovial membranes that act as cushions in places where friction develops
Order of conn. tissue on muscles:
Muscle fiber - endomysium - fascicles - perimysium - bundles - epimysium
What serve as a trigger for muscle contraction by binding to troponin to remove tropymyosin off binding sites?
Calcium ions, Ca2+
What diffuses across the membrane, binds to receptors associated with chemically gated ion channels, untimately resulting in local depolarization of membrane?
The major function of the sarcoplasmic reticulum in mm contraction is ____
To regulate intracellular calcium concentration
Sequence for mm contraction:
motor neuron AP - neurotrans release - mm cell AP - release of Ca+ from SR - ATP driven power stroke - sliding myofilaments
The sliding filament model of contraction involves_____
Actin and myosin sliding past eachother and partially overlapping