Dendrites ____.
a. contain the nucleus, ribosomes, and other structures found in most cells
b. are branching fibers that get narrower near their ends
c. are thin fibers of constant diameter
d. are an insulating material that cover an axon
Question 2
The endoplasmic reticulum is a ____.
a. network of thin tubes that transport newly synthesized proteins
b. site where the cell synthesizes new protein molecules
c. structure that separates the inside of the cell from the outside
d. structure that contains the chromosomes
Mouse lung stained to visualize differentiated epithelial cells and macrophages
The nucleus of Halley's Comet, taken by the Giotto probe in 1986
Reprogramming Factors in stem cells
Embryonic Stem Cells
The hemes found in cytochromes
A sampling of the modified and unusual bases found in tRNAs