Ricin is a highly toxic, naturally occurring lectin that is produced in the seed

Question

Ricin is a highly toxic, naturally occurring lectin that is produced in the seeds of the castor oil plant. Ricin binds complex carbohydrates on the surface of eukaryotic cells. To prevent ricin toxicity you must identify the carbohydrate that Ricin binds. To achieve this you perform an experiment on your cheek epithelial cells like you did in cell bio lab using peroxidase linked to ricin. The four carbohydrates you test are fucose, glucose, mannose and galactose. You find that a purple color develops when you add fucose, glucose and mannos in excess but there is no color when you add galactose. Which sugar residue does Ricin normally bind to? fucose glucose galactose mannose In your tissue printing lab some vegetables stained poorly for peroxidase (purpie) but showed intense staining with the protein stain (red). Which statement below is the best conclusion of this observation? There are low quantities of peroxidase compared to the amount of total protein present There are high quantities of peroxidase compared to the amount of total protein present There are equal quantities of peroxidase and other proteins present You cannot make a conclusion about peroxidase and protein quantities based on this observation Which structure in the trachea contains the highest concentration of tubulin? cilia of the epithelium cartilage layer muscle layer nuclei of the epithelium

Explanation / Answer

Answer:

3. (c) galactose

Ricin B chain binds complex carbohydrates on the surface of eukaryotic cells containing either terminal N-acetylgalactosamine or beta-1,4-linked galactose residues.

4. (a) There are low quantities of peroxidase compared to the amount of total protein present.

5. (a) cilia of the epithelium

Alpha tubulin can be found in the trachea. The mucosa is composed of ciliated columnar epithelial cells.

Related Questions

Navigate

• Browse (All)
• Browse R
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.