Assume as what happens in a pot of water as it get heats.. hot becomes less dense, rises and cools, becoming more dense then sinks- that's called CONVECTION
So D- is the right answer
Answer:
human embryonic stem cells are obtained from embryos, thereby they are subject to ethical, religious, political and legal considerations
Explanation:
Human embryonic stem cells (HESCs) are pluripotent undifferentiated cells derived from blastocyst-stage embryos, which have the ability to produce any type of somatic cells. HESCs are obtained <em>in vitro</em> from embryos that are 5-6 days old. These cells are valuable tools in research in order to understand the genetic and physiological mechanisms of human development, as well as to develop treatments against diseases. The use of embryonic stem cells in research is controversial because these techniques involve the destruction of human embryos, and there are people who consider human life begins with the formation of the diploid zygote after fertilization, thereby raising the debate if a human embryo can be regarded as a human being.
Answer:
Protozoa are one-celled organisms, like bacteria. But they are bigger than bacteria and contain a nucleus and other cell structures, making them more like plant and animal cells. Protozoa love moisture.
Answer:
Pollination of plants
Explanation:
This species of birds is thought to help in preserving and conserving the native plant species of Hawaii by helping in dispersing their seeds. They are the main pollinators of the ieie vine. These was a role that was once performed by the long extinct Hawaii native bird species (they became extinct due to the invasion of these Japanese white eye).