Answer:
a. A hypothesis that does not generate a testable prediction is not useful.
Explanation:
In the scientific method, we generate a hypothesis to explain a phenomenon. After this, it is necessary to create a method to test the hypothesis and make predictions. Moving forward, we test this methodology, generating results and reject or not reject the hypothesis. If the hypothesis can't be tested, the scientific method can't be applied.
Fetus can survive an extra copy of a chromosome, but being hemizygous is <span>usually fatal</span>
Answer:
Option D, A subject is observed both before and after two exposures to the treatment.
Explanation:
In A-B-A-B design the alphabets have following meaning
a) First A – It is the baseline value or the value measured before treatment
b) First B – It is the treatment measurement
c) Second A - It is the withdrawal of treatment
d) Second B – It is the reintroduction of treatment
The second A is known as the reversal phase in which the intervention is withdrawn to see if the target behavior returns to the baseline behaviour
Thus , there are two measurements involved one before the intervention and second after the intervention
Option D is correct
Answer:
Option a is the one, that is true.
Sister chromatids separate in anaphase of mitosis and anaphase Il of meiosis
Explanation:
After the interphase in the cell division cycle, the mitosis process begins, which is composed of 4 phases, prophase, metaphase, anaphase and telophase. The prophase occurs when the chromatin is condensed and the mitotic spindle is formed, the metaphase the chromosomes align along the cell equator, in the anaphase the separation of the sister chromatids occurs and in the telophase finally the heterochromatin is converted into euchromatin and the envelope is formed nuclear cell.
Meiosis, which is the cell division of germ cells, also has the same phases but they occur on two occasions: prophase I, metaphase I, anaphase I and telophase I for meiosis I and for meiosis II, prophase II, metaphase II, anaphase II and telophase II. In the anaphase I the homologous chromosomes are separated, they are condensed in the prophase II while in anaphase II the chromatids are separated.
