1 If the black lines aren't visible on the external screen, the laptop screen may need to be replaced. 2  If the black lines are also visible on the external screen, the video card or motherboard may need to be replaced. 3  In some cases, a loose video card can cause problems with the monitor video.
1. segmentation - (embryology) the repeated division of a fertilised ovum. cleavage. embryology-the branch of biology that studies the formation and early development of living organisms. cell division, cellular division-the process in reproduction and growth by which a cell divides to form daughter cells.
Segmentation gene. Definition. noun, plural: segmentation genes. (1) Any of the genes involved in the early stages of pattern formation in the embryo. (2) A zygotic gene responsible for the formation of body segments.Supplement. The segmentation genes are classified into three groups: gap genes, pair-rule genes, and segment polarity genes.In Drosophila, the segmentation genes code for products responsible in forming stripes or segments in the fruit fly embryo. See also: zygotic gene.1) Any of the genes involved in the early stages of pattern formation in the embryo. (2) A zygotic gene responsible for the formation of body segments. Supplement. The segmentation genes are classified into three groups: gap genes, pair-rule genes, and segment polarity genes.