The maintain homeostasis in the cell by controlling what comes in and out of the cell.

cell membrane

nucleus

cell barrier

cell door

Bone-strengthening physical activity done increases bone-mineral content and bone density in youth.

True or false when elements combine to form a mixture, the resulting chemical properties may be very different from those of the elements that make it.

**urgent** roberto plans to use two transformers to reduce a voltage of 120 v to 4 v. he uses a transformer that has 300 coils in the primary winding and 50 coils in the secondary winding. he has four other transformers, as listed in the table. which transformer should roberto use to have an ending voltage of 4 v? a- w b-xc- yd- z