<span>Rough ER is called rough because it has ribosomes attached to its surface. The double membranes of smooth and rough ER form sacs called cisternae. Protein molecules are synthesized and collected in the cisternal space/lumen. When enough proteins have been synthesized, they collect and are pinched off in vesicles.</span>
Answer:
It would be B
Explanation:
By doing the punnet square, you get BB, BB ,Bb, Bb, of which 50% are heterozygous.
Answer:
If the two magnets have their two N poles pointing up then when they are side by side they will repel each other but when they are head-to-tail they will attract.
Explanation:
so a positive and a negative will attract
The immune system, and the excretory system
(Honestly, all of them work to keep us 'healthy', but I believe these are the ones you're looking for)