10. Which of the following structures is shaped like a hollow cylinder made out of tubulin proteins?
a. Intermediate filaments
b. Microtubules
c. Microfilaments
d. Flagella

11. The cell organelle responsible for the packaging of proteins is the
a. ribosome.
b. Golgi complex.
c. rER.
d. lysosome.

12. Which of the following cell organelles contain digestive enzymes?
a. Mitochondria
b. Chloroplasts
c. Lysosomes
d. Peroxisomes