The purpose of the uninoculated control tubes used in this test is that two uninoculated control tubes are needed to show the results of the medium in both aerobic and anaerobic environments. It is used to show it is sterile and also as a color comparison, used also to show that the medium remains green under both conditions.
Answer:
The outer core of the earth is liquid.
Explanation:
Seismic waves travel through the Earth at different speeds and are reflected and refracted diffracted differently as they encounter layers of different densities.
By analyzing these waves, they have concluded that there is an inner core of solid iron surrounded by a liquid outer core consisting of nickel and iron.
A is wrong. The Earth consists of several layers
C is wrong. Seafloor spreading is caused by the movement of tectonic plates away from each other.
D is wrong. The mantle is mostly solid rock.
<span>Since the early 1990s, geneticists have produced "genetically modified" crops that yield fruits and vegetables commonly found in U.S. supermarkets. Genetically modified plants (and also applicable to animals) in agriculture are those plants whose DNA are being modified using genetic engineering techniques.</span>
Answer:
Explanation:
Increasing the solute would increase the concentration. Increasing the solvent would decrease the concentration. For instance, if your lemonade was too tart, you would add more water to decrease the concentration. If your tea was too bitter, you could add more sugar to increase the sweetness. Changing the amounts of solute and solvent directly effect the concentration of the solution.