In humans, the placenta is essential to the embryo for RESPIRATION, NUTRITION AND EXCRETION.
The placenta refers to an organ in the uterus of pregnant mammals that is responsible for nourishing and maintaining the unborn baby through the umbilical cord. Th placenta has many functions but primarily it plays critical roles in the nutrition, respiration and excretion of the fetus. Its other functions include: production of hormones, production of immunity for the fetus for prevention from infections, etc. <span />
The first living things on Earth, single-celled micro-organisms<span> or microbes lacking a cell nucleus or cell membrane known as prokaryotes, seem to have </span>first<span> appeared on </span>Earth<span> almost four billion years ago, just a few hundred million years after the formation of the </span>Earth<span> itself.</span>
Answer: Option D) China
Explanation:
From the picture provided, China and USA contributes above 5.000.000 ( In thousands of metric tons) of carbon dioxide emissions.
And since carbon dioxide has been implicated in the emergence of global climate change, both countries are leaders in the emission.
Thus, China is the right option
The correct answer is D. Heat is transferred by radiation in Step 1 and by conduction in Step 2
radiation- the process of heat moving through the air
conduction- the process of heat moving from one object to another object by physical contact