After the third dose -- given at age 6 months -- your child will be 80% to 85% immune to whooping cough for 3 to 5 years. Everyone -- including adults -- from age 11 up should receive a booster vaccine, called Tdap. It's a combined tetanus, diphtheria, and pertussis booster vaccine.
How many chromosomes are in the nucleus of an onion root cell? There are 8 chromosomes in the nucleus of an onion root cell. The cells are undergoing mitosis, during which the amount of DNA is doubled even as the number of chromosomes â¦ remains constant. How many chromosomes do onions have?
Cells normally contain 23 pairs of chromosomes, or a total of 46 chromosomes each. Chromosomes are inherited from both parents, of which 22 pairs are autosomes and one pair is composed of sex chromosomes. Sex chromosomes determine the gender of the child.hen one chromosome in a given pair is missing, it is called a monosomy. One example is Turner syndrome. A trisomy occurs when an additional chromosome appears in the genetic make-up of an individual. Examples are Down syndrome, Patau syndrome, Klinefelter syndrome and Edward's syndrome.