Whether it is brand-new or years old, a mattress too soft for your comfort level may make for many restless nights. As long as the mattress is in good shape, there's no need to replace it to achieve the desired level of firmness.Instead, purchase a firm topper, slide a bed board beneath the mattress, or add extra support to the bed frame itself. sheet of plywood cut to the same size as the mattress offers support for a mattress that has lost some of its firmness. Slide the plywood between the mattress and box spring.
Human cells normally contain 23 pairs of chromosomes, for a total of 46 chromosomes in each cell (illustration). A change in the number of chromosomes can cause problems with growth, development, and function of the bodyâs systems.
The mutation changes the gene's instructions for making a protein, so the protein does not work properly or is missing entirely. This can cause a medical condition called a genetic disorder. You can inherit a gene mutation from one or both parents. A mutation can also happen during your lifetime. There are three types of genetic disorders: 1  Single-gene disorders, where a mutation affects one gene. 2  Chromosomal disorders, where chromosomes (or parts of chromosomes) are missing or changed. 3  Complex disorders, where there are mutations in two or more genes.