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?
Mapped in 2007 by the Horse Genome Project, the genetic material of a horse includes 2.7 billion DNA base pairs inside each chromosome. Other animals with 64 chromosomes are the chinchilla, the fennec fox and the spotted skunk. Donkeys, which have 62 chromosomes, are bred with the domesticated horse to produce mules, which have 63 chromosomes.