The contraction produced can be described as a twitch, summation, or tetanus, depending on the frequency of action potentials. In skeletal muscles, muscle tension is at its greatest when the muscle is stretched to an intermediate length as described by the length-tension relationship. Smooth and cardiac muscle contractions are myogenic and can be modulated by the autonomic nervous system.
sex-linked disorder - any disease or abnormality that is determined by the sex hormones; hemophilia is determined by a gene defect on an X chromosome. bleeder's disease, haemophilia, hemophilia - congenital tendency to uncontrolled bleeding; usually affects males and is transmitted from mother to son.
Sex-linked traits are genetic characteristics determined by genes, which are located on sex chromosomes. Genes are segments of DNA found on chromosomes that carry information for protein production and that are responsible for the inheritance of specific traits. Genes exist in alternative forms called alleles.enes that are found on the sex chromosomes are called sex-linked genes. These genes can be on the X chromosome or on the Y chromosome. If a gene is located on the Y chromosome, it is a Y-linked gene.