Answer: Racial classification
Explanation: Racial classification can be defined as the way humans are classified based on their physical and social traits which they have such as how they look, their skin color, hair texture, the native languages they speak.
Scientists used racial classification to learn how unique and different humans are.
D. Fold mountain that appeared wavy I think but just in case check an other answer
Answer: A, a structure that has no use in the organism
Explanation:
A vestigial structure is an anatomical feature that no longer seems to have a purpose in the current form of an organism of the given species.
"Meiosis" is the process that <span>maintains a constant number of chromosomes within a species
Hope this helps!</span>
Answer:
The correct answer is internal and external signals regulate the progression of the cell cycle at various critical check points.
Explanation:
The cyclic event that helps to prepare the cell for division is termed as cell cycle.Cell cycle are regulated by various internal and external factors which regulates the passage of cell through various critical check point.
For example Maturation promoting factor helps in the progression of frog egg oocytes cells from G2 to M phase.
G1 cyclin CDK helps in the passage of cell from G1 to S phase.