I think they contain covalent bonds, between the carbon atoms and also between the carbon atoms and hydrogen atoms. Polymers consist of chain-like molecules that are in turn, made up of numerous smaller, repeating units called monomers.
Answer:
d. mucosa, submucosa, muscularis, serosa
Explanation:
The layers of the digestive tract starting from the lumen are mucosa, submucosa, muscularis and serosa.
- The first layer is mucosa which is made of epithelium cells and helps in absorption of nutrients from digested food. It has numerous villi structure which increase the surface area for absorption.
- Second layer submucosa supports mucosa and is supplied with large blood vessels, nerves and lymphatics. Absorbed nutrients enter the blood vessels which are present in submucosa.
- The third layer muscularis functions to create peristaltic movements in GI tract. Muscles in this layer make the food move and mix with digestive juices.
- Final layer serosa works to reduce friction between digestive tract muscles. It has a thin cell layer which secretes serous fluid that acts as a lubricant.
Saliva contains relatively few microbes compared to other body sites, because the concentration of antimicrobial enzymes limits their growth.
Animals or us humans because we were animals we had the first cell i think
The answer is <span>C. Fructose and glucose.
A disaccharide is a carbohydrate composed of two (prefix di-) monosaccharides bound by glycosidic bonds. The only monosaccharides among all choices are fructose and glucose. They together form disaccharide sucrose.
Other choices could not be correct because all mentioned molecules are not carbohydrates at all.</span>