B cells play a crucial role in the defense of pathogens. They are responsible for producing antibodies that help fight the enemy.
Answer:
See the answer below
Explanation:
The Chi-square (
) is calculated by the formula:
= 
where O = observed frequency and E = expected frequency
A standard dihybrid cross is expected to give 9:3:3:1 phenotypic ratio.
Phenotype O E
Round yellow 104 9/16 x 160 = 90 
= 2.18
Round green 27 3/16 x 160 = 30 
= 0.30
wringled yellow 27 3/16 x 160 = 30 = 0.30
wrinkled green 2 1/16 x 160 = 10 
= 6.40
Total value to two decimal places = 9.18
Degree of freedom = (n-1) = 4 -1 = 3
Critical value at 95% probabillity level = 7.815
<em>Since the calculated </em><em> si more than the critical </em><em> value, </em><em>the null hypothesis is rejected. </em>
By listening to radioactive waves
Answer:
Explanation:
In the members of the class ascomycetes such as yeast, two haploid yeast cells of two different stains or mating types fuse to form a diploid zygote. Zygote quickly undergoes meiosis or reductional division to form four haploid spores called a tetrad. The tetrad is contained in a sac-like structure called an ascus or fruiting body. Formation of ascus is the characteristic feature of ascomycetes. In the ascus tetrad are not arranged in any specific order. The tetrad are called random or unordered spores. The genetic analysis of the genotypes in the tetrad can tell us about the events during meiosis.
