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?
BRIEF DESCRIPTION. In this simple experiment, students will prepare slides of red onion cells to be viewed under the microscope. Onion cells are easily visible at medium magnification. Their plasma membrane and cytoplasm can be clearly distinguished, and, if a stain is used, their nuclei can be seen, as well. Students will also observe that the cells are uniform in shape and size. This is a consequence of mitotic cell divisionâwhich produces genetic clones and contributes to the development of specific tissues, each made up of distinct cell types with distinct functions (in this case, inner epidermal cells).