Answer;
-Bone tissue becoming stronger.
The mechanical stress applied to bones during moderate physical exercise leads to bone tissue becoming stronger.
Explanation;
-Bones and muscles both become stronger when muscles push and tug against bones during physical activity.Swimming and bicycling are not weight-bearing activities, so they do not directly help build bones. But swimming and bicycling do help build strong muscles, and having strong muscles helps build strong bones.
-Weight-bearing physical activity causes new bone tissue to form, and this makes bones stronger. This kind of physical activity also makes muscles stronger. Bones and muscles both become stronger when muscles push and tug against bones during physical activity.
Answer:
1.Plasma membrane
The plasma membrane surrounds the cell to create a barrier between the cytosol and the extracellular matrix. Plasma membranes also enclose lumens of some cellular organelles.
2.Endoplasmic reticulum
The endoplasmic reticulum (ER) is a large network of membranes responsible for the production of proteins, metabolism and transportation of lipids, and detoxification of poisons. There are two types of endoplasmic reticulum with separate functions: smooth endoplasmic reticulum and rough endoplasmic reticulum. The presence or absence of ribosomes in the ER’s plasma membrane determines whether it is classified as smooth or rough ER.
3.Golgi apparatus
The Golgi apparatus appears as a series of flattened, membranous sacs, or cisternae, that resemble a stack of pancakes just off the rough endoplasmic reticulum. It receives vesicles containing proteins recently produced by the rER. The Golgi apparatus can be compared to a warehouse or post office for newly formed proteins. Here the proteins are further modified, packaged, and sent off to their final destinations in the cell or body.
The correct answer is C: the gravitational forces due to the sun and the moon cancel each other's effect.