Mechanical stress applied to bone increases osteoblast activity in bone tissue, and the removal of mechanical stress decreases osteoblast activity.
Explanation:
Osteoblasts are cells , that are produced in the bone marrow and are responsible for formation of bones and bone matrix.
Whenever a mechanical stress is applied on the bones , a series of reactions are triggered. As a result the activities of osteoblast increases to synthesize more and more bone matrix to provide strength.
Again on the other hand a decrease in mechanical causes a decrease in the activities of the osteoblasts.
The percentage of the stroke volume is ejected during the first quarter of systole will be approximately 60% to 65%
<u>Explanation:</u>
The time interval between the atria contraction and the relaxation of ventricles are called as a Cardiac cycle. Systole denotes the heart contraction during the blood pumping. Diastole refers to the heart relaxation when the blood is filled in the heart chambers. The total blood is not fully pumped by the ventricles.
Instead they will pump only a proportion of blood in each of the cardiac cycle. The ejection fraction refers to the proportion of the intraventricular volume that is received as a output in circulation process. A human with normal heart functioning can have approximately 60-65%. This is known to be stroke volume. The blood volume that is ejected is strove volume.
Is that they all have the same routine
Answer:25 , 0
Explanation:
XX©(mother being the carrier as her father was hemophilia- females can only be carrier of hemophilia ) when crossed with normal father produces offspring XX©, XY, XY©, XY. Therefore chances of boy being hemophilia=(1/4)*100=25.
Chances of girl being hemophilia= 0.
A chemical change has occurred because the wood has turned into a substance that can't be changed back to it's original form. The wood has turned to ash, chemical changes are non reversible.
