What do the numbers 3 and 4 refer to in 3nh4

The number 3 means that there are 3 molecules of ammonium while the 4 refers to the fact that there are 4 atoms of hydrogen in the compound.

The compound 3NH₄ given is known as ammonium.

It is a compound that is made up of 3 atoms of Nitrogen and 12 atoms of Hydrogen.

The ammonium compound is NH₄ while the 3 at the back of the ammonium compound means there are 3 molecules of ammonium.

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The 4 that serves as subscript shows that there is the presence of 4 atoms of hydrogen since the value of directly attached to the hydrogen atom.

an individual’s sex (i.e., whether they are a male or female) is determined by the sex chromosomes. most people have two sex chromosomes, one that is inherited from their mother and one that is inherited from their father. typically, females have two x chromosomes (xx) and males have one x chromosome and one y chromosome (xy). conditions caused by changes (“mutations”) in genes located on the x chromosome are considered x-linked.

x-linked recessive inheritance

most x-linked conditions are recessive. this means that in a person with two x chromosomes (most females), both copies of a gene (i.e., one on each x chromosome) must have a change or mutation whereas in a person with one x chromosome (most males), only one copy of a gene must have a mutation. a female with a mutation in one copy of a gene on the x chromosome is said to be a “carrier” for an x-linked condition. a male with a mutation in a gene on the x chromosome is typically affected with the condition. because females have two copies of the x chromosome and males have only one x chromosome, x-linked recessive diseases are more common among males than females. however, x-linked recessive diseases can occur in both males and females.

for x-linked recessive disorders, an unaffected carrier mother who has a mutation in a gene on the x chromosome can transmit either the x chromosome with this mutation or a “normal” x chromosome to her children. if the father is unaffected, none of her daughters will be affected and all of her daughters will be unaffected—since they will inherit at least one normal x chromosome from their father. however, each daughter will have a 50% chance of being an unaffected carrier like her mother and a 50% chance of both x chromosomes being normal.

b a mature ovary of a plant.