#Question id: 1753
#Unit 4. Cell Communication and Cell Signaling
In the germinal center, B-cells become memory cells under the influence of:
#Question id: 5657
#Unit 5. Developmental Biology
Following statements regarding to the molecular processes of capacitation.
A. The sperm cell membrane is altered by the removal of cholesterol by albumin proteins in the female reproductive tract.
B. Particular proteins or carbohydrates on the sperm surface are lost during capacitation.
C. The membrane potential of the sperm cell becomes more positive as potassium ions leave the sperm. This change in membrane potential may allow calcium channels to be opened and permit calcium to enter the sperm.
D. Calcium and bicarbonate ions are critical in activating cAMP production and in facilitating the membrane fusion events of the acrosome reaction.
E. As a result of cAMP formation, protein phosphorylation occurs. Once they are phosphorylated, some proteins migrate to the surface of the sperm head. One of these proteins is juno, which is critical in sperm-egg fusion.
which one of the following combinations is correct?
#Question id: 29589
#Unit 6. System Physiology – Plant
Which one of the following reactions takes place during the reduction phase of the Calvin- Benson cycle?
#Question id: 31030
#Unit 4. Cell Communication and Cell Signaling
#Question id: 23169
#Unit 13. Methods in Biology