Adenine and guanine have a fused-ring skeletal structure derived of purine, hence they are called purine bases. ... Similarly, the simple-ring structure of cytosine, uracil, and thymine is derived of pyrimidine, so those three bases are called the pyrimidine bases.
Answer:
Sex cells are the only cells that undergo meiosis.
Explanation:
Sperm cells in male and egg cells in female are the sex cells because these cells are responsible for the formation of new organism. When the sperm sex cell fuse with egg sex cell forming zygote which turns into a new organism. Mitosis occurs in somatic cells while meiosis occurs only in sex cells.
Leeuwenhoek - Advanced microscope
Schleiden - Plants made of cells
Schwann - Animals made of cells
Virchow - New cells from old cells
The validity of the hypothesis cannot be confirmed or refuted from only one experiment. By using a series of experiments, the human error or measurement error is reduced to a minimum. Furthermore, more than one factor can be used to determine the validity of the hypothesis.
I will respond to this student that the experiment needs to be repeated multiple times before a conclusion can be drawn! Also, the data will refute or confirm the validity of the hypothesis and not the researcher's own opinion/rational.