Teratogens are agents or factors that causes malformation of an embryo they include alcohol,cigar smoke, drugs, maternal stress and paternal age. At the embryonic period the unborn baby is at a very high risk of developing structural defects ddue to the effects of teratogens. Teratogens may lead to abnormal development in muscles, tendons and bones.
Hi! they are mainly composed of phospholipids and proteins. :)
Each tissue is an organized assembly of cells held together by cell-cell (more...) In epithelial tissue, by contrast, cells are tightly bound together into sheets called epithelia. The extracellular matrix is scanty, consisting mainly of a thin mat called the basal lamina, which underlies the epithelium.