Answer:
Nn
Explanation:
Tay-Sachs disease is an inheritable genetic disorder that results in the destruction of nerve cells in the brain and spinal cord. It's caused by the absence of an enzyme that helps break down fatty substances called gangliosides. Their buildup results in the destruction of nerve cells.
Tay-Sachs is inherited in an autosomal recessive manner. This means that a person needs to have two recessive alleles (nn) in order to inherit it. Rebecca is a carrier of the disease but isn't actually ill. This means that she has one recessive (n) and one dominant (N) allele. Thus, her genotype is Nn.
Tl = thallium
look at the periodic table look for element number 81 on the periodic table and that's TI
It's mass number is 204.38
Answer:
chemical reactions.
Explanation:
Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. These processes are called chemical reactions and, in general, are not reversible except by further chemical reactions.