What is the function of glycoproteins?

1) to allow specific ions or molecules to pass freely
2) to serve as identification for the cell
3) to actively carry specific ions or molecules into the cell
4) to detect bacteria and other foreign bodies outside of the cell

A60-tooth gear is connected to a 72-tooth gear.if the smaller gear turns 12 times,how many turns does the larger gear make?

Once an egg cell is fertilized by sperm, the cell then, as the embryo develops, it receives nourishment and eliminates wastes by transferring substances from its blood to its mother's blood. a. becomes a fetus immediately and exits the womb b. begins to divide and implants itself in the wall of the uterus c. remains in the uterus without dividing for several months d. travels back to the ovaries until the fetus is developed

Why zebra fish experience similar genetic disease as human