Do whatever she feels and I would support her in anyway or any road she takes.
Sunlight is the main change! sun light cannot penetrate into the deep layers of the ocean and availability of oxygen is also low there. this causes the considerable amount of organisms to live in the upper layers of the ocean and we can only observe decomposing organisms in the deeper layers!
By definition, a body system is primarily comprised of different organs and tissues that work one another to achieve a common body process. These body systems would include:
Circulatory system - concerns with the circulation of blood
Digestive system - breaking down of food particles
Skeletal system - composed of bone structures serving as our body's framework
Nervous system - composed of nerve cells that responds to different stimuli
Respiratory system - concerns of utilising the entry of oxygen and the exhalation of carbon dioxide.
It has meanwhile been shown that the most sensitive cells are those that areundifferentiated, well nourished, dividing quickly and highly active metabolically. Amongst the body cells, the most sensitive are spermatogoniaand erythroblasts, epidermal stem cells, gastrointestinal stem cells.
Hoped this helped!