D is the answer (Aa and aa ) i hope this helps
Answer:
There are 2 alleles, a recessive allele and a dominant allele. The weaker allele is the recessive allele.
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.
Answer:
d.smooth muscle
Explanation:
Blood vessels contain only smooth muscle cells. These muscle cells reside within the tunica media along with elastic fibers and connective tissue
Answer:
O silicon (Si)
Explanation:
-Valence electrons are electrons of the outermost shell which can participate in chemical bonding. ... -As in silicon, four electrons are present in the outermost shell, so silicon has Four valence electrons.