Ptolemy was an astronomer and mathematician. He believed that the Earth was the center of the Universe. The word for earth in Greek is geo, so we call this idea a "geocentric" theory.With the development of the heliocentric model by Nicolaus Copernicus in the 16th century, the Sun was believed to be the center of the Universe, with the planets (including Earth) and stars orbiting it.
Answer:
D. they are unicellular
Explanation:
unicellular organisms are not part of the kingdom animalia .Animalia consists of aves(birds),amphibians,reptiles,mammals and so on and all these organisms are multicellular that is having more than one cell.
Out of the following give choices;
a. All DNA strands
contained only the heavy nitrogen isotope.
b. Half of the DNA strands contained only the light nitrogen
isotope.
c. All DNA strands contained both heavy and light nitrogen
isotopes.
d. All DNA strands contained only the lighter nitrogen
isotope.
The answer is b. Meselson–Stahl experiment demonstrated the semi-conservative model of DNA replication.
When DNA is replicated, one strand of the new double
helix strand is the parent's strand while the other is the newly synthesized
one. This made the semiconservative model stand out over the other two, dispersive
and conservative models.
<span>The movement of fluids between cellular compartments is regulated by osmotic and hydrostatic forces.</span>
<span>
Hydrostatic pressure<span> is the force exerted by a fluid against a wall which causes movement of fluid between compartments. This pressure is important for exchanging plasma and nutrients between capillaries and surrounding tissues</span> and also in the nephrons (kidneys) where ensures proper filtering of the blood to form urine.</span> <span>Fluid also moves between compartments along an osmotic gradient (the difference in concentration of solutes on one side of the cell membrane to that on the other side). Water constantly moves into and out of fluid compartments via osmotic gradient.</span>
