Answer: The correct answer is-
an agent that causes a mutation in DNA.
Mutagen is an agent or a substance that causes permanent change in the genetic material of living organisms ( DNA, deoxyribonucleic acid). This process is called mutation.
A mutagen can be a chemical, physical or biological agent that causes mutation in the DNA.
Example- Physical agents such as -
- Ionizing radiations like alpha particles, gamma rays, X-rays that brings break in the DNA and cause other damages.
- Ultraviolet radiations that creates pyrimidine dimers ( T=T) and causes replication errors if damage is not repaired.
Answer and Explanation:
The cell division cycle is responsible for increasing and maintaining cell number and size. This cycle is an essential feature of living organisms. There are four phases of cell division mitotic phase (M phase), growth phase 1 (G1), growth phase 2 (G2), and synthesis phase (S). One phase of the cell cycle ends, and the other starts; this is named a phase transition—a unidirectional alteration in the cell cycle phases. During G1, G2, and S phase cell grows and during the M phase cell divides. There are two models of cell reproduction as the clock model and the domino model. The domino model implies that cell division phases must occur in a distinct order and at a definite time. The domino model recommends that the cell cycle events are independent, while the clock model shows that the effectiveness of mitosis entrance was not persuaded by other actions.
Answer:
east to west
it is hard because we have to take care of each and every tempreture
<span>There are 46 chromosomes in a human zygote.
</span><span>Source(s):
Google. I also know this, just to make sure you know my answer is right!
</span><em>When the gametes join they form a cell called a zygote. Human sperm and eggs contain 23 chromosomes</em><span><em>. Human zygotes contain </em></span><em>46 chromosomes</em><span><em>. The type of cell division that produces gametes with half the normal chromosome number is called meiosis.</em></span>