Animal cells are unique in that they do not exhibit cell walls.Plant cells exhibit very stiff pecto-cellulosic walls, notably because of the presence of cellulose microfibrils, the stiffness of which compares to that of steel.
Answer:
they are not living
Explanation:
Viruses are not living things. Viruses are complicated assemblies of molecules, including proteins, nucleic acids, lipids, and carbohydrates, but on their own they can do nothing until they enter a living cell. Without cells, viruses would not be able to multiply. Therefore, viruses are not living things
Answer:
¨ An S wave, or shear wave, is a seismic body wave that shakes the ground back and forth perpendicular to the direction the wave is moving.¨
Explanation:
Neon is a non-reactive gas, because it <span>has a full outer energy level and does not wish to lose or gain any electrons. (Solution:B) Non-reactive gases have filled outer shells and </span>form no significant compounds. The electron configuration of the gas is responsible for the reactivity of the gas. The <span>electron orbital of the Neon that is filled with eight electrons.</span>
Question is incomplete. Complete question is as follows:
The ____ abuts the lumen of the alimentary canal and consists of epithelium, lamina propria, and muscularis mucosae.
Answer:
Mucosa
Explanation:
Mucosa or mucosal membrane forms the lining of many cavities in the body like the alimentary canal and also covers many internal organs. It lines reproductive, digestive and respiratory system. In the gastrointestinal tract the mucosa is made of three layers: epithelium, lamina propria and muscularis mucosae.
The epithelium of mucosa is made of simple columnar epithelium cells. It consists of many types of cells like parietal cells (secrete HCL) and foveolar cells (secrete mucus). Lamina propria is a loose connective tissue present beneath the epithelium. It provides nutrition and support to epithelium. Muscularis mucosae has smooth muscle fibers which helps the glands on the surface to secrete their contents and also increase the contact between contents of lumen and epithelium.
