Which of the following statements are correct? a. The morula stage involves cleavage of the zygote.
b. The gastrula stage involves differentiation of cells.
c. The blastula stage involves rearrangement of the cells to form a hollow sphere
d. All of the above.
e. None of the above.

the calvin cycle has three stages. in stage 1, the enzyme rubisco incorporates carbon dioxide into an organic molecule. in stage 2, the organic molecule is reduced. in stage 3, rubp, the molecule that starts the cycle, is regenerated so that the cycle can continue

the three components of a nucleotide are the nitrogenous base, the phosphate group and the five-carbon sugar.

the earth is thought to have been formed about 4.6 billion years ago by collisions from a cloud of hydrogen, helium, rock, ice and other materials. these were pulled together by gravity to form objects in and around earth like- asteroids and small early planets called planetesimals.

so, the best possible answer to this question will be option d- to harden materials to form different parts of earth’s layers