<span>Primary immunodeficiencyvdiseases are a group of more than 250 rare, chronic disorders that affect how the body’s immune system works. Primary immunodeficiency diseases are caused by genetic defects. I hope this helped</span>
The correct answer is A.
The use of antibacterial drugs can cause modifications in the genetic material of the concerned bacteria. If the genetic material of the bacteria are modify, that means they have undergone mutation. Because the base sequence of the normal and that of the mutated gene is different, antibiotic will not be able to recognize the bacteria again and thus will not be able to attack it.
Answer:
D. Useless
Explanation:
According to Dictionary.com, “in vain” is defined as “without real significance, value, or importance; baseless or worthless.”
Answer:
D. The first division will reduce the number of chromosomes by half for each daughter cell, and the second division will move single chromatids to each daughter cell.
Explanation:
Gametes are formed by meiosis in diploid gamete mother cells. During gamete formation, the gamete mother cell in the yeast would undergo meiosis I. During first division (meiosis-I), the process of crossing over during prophase-I creates genetic variations and movement of homologous chromosomes to the opposite poles during anaphase-I reduces the chromosome number to half in each daughter cell.
Two daughter cells are formed by the end of meiosis-I each of which enters meiosis-II. Splitting of centromere and separation of sister chromatids during anaphase-II of meiosis-II results in the movement of single chromatids to the opposite poles of the cells.