A dominant gene will always be expressed when present, such as in the homozygous dominant genotype (RR), or heterozygous genotype (Rr). A recessive allele is only expressed wh â¦ en the genotype is homozygous recessive (rr).
(Lung alveoli, in contrast, are lined by very thin simple squamous epithelium .). Pseudostratified respiratory epithelium consists primarily of columnar ciliated cells. Ciliary beating sweeps mucus and the dust it carries up the bronchi and trachea toward the pharynx, where it can be swallowed.
A simple columnar epithelium is a columnar epithelium that is uni-layered. In humans, a simple columnar epithelium lines most organs of the digestive tract including the stomach, small intestine, and large intestine.Simple ciliated columnar epithelia line the uterus.iliated columnar epithelium moves mucus and other substances via cilia and is found in the upper respiratory tract, the Fallopian tubes, the uterus, and the central part of the spinal cord .They are the primary target of infection for common cold viruses such as coronaviruses, influenza virus and rhinoviruses.