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?
Onions. Onions are such a versatile vegetable â they feature in so many recipes, and growing your own means youâll always have them to hand. They are easy to grow from baby onions, which are called sets. Although seed is available, sets are the easiest and quickest way to grow onions. Sets are also are better in colder regions, and are less likely to be attacked by some pests and diseases.