Answer: The mass number is 13
Explanation:
Mass number = Protrons + neutrons;
While Atomic number = Number of neutrons
Therefore, if the atomic number of nitrogen is given as 7, then its Protrons = 7
So, mass number = 7 + 6 = 13
Point source means: the pollution that comes from a single point (examples)
Sewage pipes releasing sewage into a ditch
Smokestack style factory chimneys
Oil pipes
Pollution which is caused by rain fall or snow melting into the ground. As the runoff moves, it picks up and carries away natural and human made pollutants, Finally reaching a lake, river, ocean, groundwater.
The atomic number of an element is the number of protons in the nucleus of an atom of that element.
Atoms with the same number of protons, but a different number of neutrons are called isotopes.
Answer:
Recessive
Explanation:
A recessive disorder is expressed in a homozygous genotype only. Most of the recessive disorders are not expressed as the expression of the recessive allele is masked by a dominant allele in the heterozygous state. However, breeding between close relative (inbreeding) increases the homozygosity in the population and allows the expression of recessive alleles that were otherwise not expressed in the population.
According to the given information, the disease is rare and is mostly expressed in the progeny obtained by mating between closely related individuals (the first cousins). Therefore the disease is inherited in an autosomal recessive pattern.
