The answer is B
Hope this helps
Viruses are not always classified as living cells because they cannot live independently. They rely on a host to provide all resources to live, without a host they are in a dormant, near dead like state. Therefore it has to define a virus as dead or alive as it may or may not have a host.
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The second A is known as the reversal phase in which the intervention is withdrawn to see if the target behavior returns to the baseline behaviour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:
The t-test
Explanation:
<em>The researcher should use a t-test to compare the two means and check if they are significantly different from each other.</em>
In using the t-test, both null (H0) and alternate (H1) hypothesis are made such that:
Thereafter, the value of t is calculated and compared to its critical value on the table. The formula for calculating the t goes thus:
where, Y1 = mean of population 1, Y2 = mean of population 2, S1 = variance of population 1, S2 = variance of population 2, n1 = number of individuals in population 1 and s2 = number of individuals in population 2.
<em>At the end of the day, if the calculated t value is more than the critical value of t, the H0 is rejected and it shows that the two means are significantly different. Otherwise, the H0 is accepted and this shows that there is not significant difference between the mean of population 1 and that of 2.</em>
Answer:
A. anaerobic respiration in muscle cells, forming lactic acid
Explanation:
Running marathon is a vigorous exercise, which often leads to excessive use of oxygen in the cells of the athlete. This causes the cells to switch from the aerobic (with oxygen) to the anaerobic (without oxygen) mode of respiration. This anaerobic respiration produces a product called LACTATE OR LACTIC ACID.
The lactic acid becomes excessive and gets stored in the muscle cells of the athlete. This often leads to cramps, muscle pulls etc. during the marathon. Therefore, an individual running a marathon may experience periods of oxygen deprivation that can lead to anaerobic respiration in muscle cells, forming lactic acid.
