Answer: B, the number of species in a community
Explanation:
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.
Infectious agents are those that corrupt and prey on an organism or a host. This is sometimes called parasitism when a foreign organism consumes a host by preying on its nutrients and food. Hence, we are uncertain in Anna's case because there is no clear description of her symptoms.
The answer to this obvious question is true
Answer:
True
Explanation:
Each replicated chromosome pairs with its corresponding homologous chromosome forming a tetrad. During tetrad formation, alleles can be exchanged between chromatids, a process called crossing-over.