Answer:
by looking at their physical features, the fossil record, and dna sequences
the answer is A
this is because in ecosystem 1 there are only predators and no other species are observed. therefore predators have less food to eat thus they will die of hunger or move to another ecosystem
The correct answer for question number 1 is A - eukaryotes are the name
for unicellular organisms that dominated earth up to the Precambrian
times.
The correct answer for question number 2 is C - the
greenhouse effect is related to the phenomenon of an increase in average
surface temperature known as global warming.
The correct
answer for question number 3 is D - the colourless and odourless gas
that is produced by the radioactive decay of Uranium-238 and is considered
to be a cancer-causing agent is Radon.
The correct answer for
question number 4 is B - Scientists can determine if oxygen existed in
Earth's Archean atmosphere by looking for oxidized iron in rocks.
The right answer is a surface glycoprotein.
The antigens of the non-self correspond to any substance foreign to the organism, identified as such by the immune system of our organism which produces an energetic defense. Antigens are usually proteins (more specifically glycoproteins) contained in cells or foreign bodies (red blood cells transfused, organs transplanted, bacteria, viruses), or present in the environment (pollen, mite droppings, cat hair , etc.).
Our body has its own antigens that allow it to have a "specific identity card" and will be recognized as foreign by other organizations. They are called "self antigens".