Given that an average human has a heart rate of 70 beats per minute and if one is to have a 70 year life span, the number of times it will beat is 2,575,440,000 times. This was computed by multiply 70 years by 365 days/year x 24 hours/day x 60 minutes/hour x 70 beats/min. Thus, the heart will beat numerous times before it finally stops.
The body wall<span> of a star fish is made up of a thin cuticle, an epidermis with a single layer of cells, a thick dermis composed of connective tissue and a thin coelomic myoepithelial layer, which allows the longitudinal and circular musculature.</span>
Answer:
<h2>Biological servises </h2><h2>Hope it helps ;)</h2>