Explanation:
Percentage w/v means that weight of solute present in 100 ml of a solution. Hence, 15% w/v means that 15 gram of solute per 100 ml of solution.
Hence, for 2 L (or 2000 mL) preparation the amount of mass will be calculated as follows.

= 300 g
Thus, we can conclude that weight of Tris-HCL required is 300 g.
Answer:
Ans. (C).Progesterone promotes fertility because its levels rise during ovulation and immediately after.
Progesterone is a female sex-hormone, produced in the ovaries right after ovulation and its level rise immediately after ovulation (as shown in graph). A thick, and proper uterine lining is important for the implantation of zygote in the uterine wall.
Progesterone has the most influence on a secure pregnancy as it promotes the thickening and maintenance of uterine lining. Low levels of progesterone makes it difficult to get pregnant as zygote cannot implant properly.
<span>Active transport is a process that removes substances from a cell against the concentration gradient. The molecules move from low concentration to high concentration during this process.</span>
Answer:
Although the word atom comes from a Greek word that means “indivisible,” we understand now that atoms themselves are composed of smaller parts called subatomic particles. The word it originated from Atomos.
Explanation: