Answer:
d.They prevent the two parental strands from coming together again.
Explanation:
During the process of DNA replication, the two DNA strands should be separated from each other to serve as a template. To separate the two DNA strands, the helicase enzyme breaks down the hydrogen bonds between the complementary base pairs of the DNA strands. The process uses ATP as a source of energy.
Due to the presence of complementary base pairs, the separated DNA strands have a tendency to reanneal by the formation of hydrogen bonds. To prevent the reannealing of separated DNA strands, single stranded binding proteins bind to them. Binding to single stranded binding proteins to the separated DNA strands does not allow them to reanneal.
The answer to your question 12
Answer:
E. combined oral contraceptives
Explanation:
Oral contraceptives will decrease a woman's risk of developing ovarian and endometrial cancer. The earlier, higher dose oral contraceptive pills have been linked to a slight increase in breast cancer, but not the most recent lower dose pills. Women who use oral contraceptive pills have a slightly higher risk of developing cervical intraepithelial neoplasia, but their risk of developing PID, endometriosis, benign breast changes and ectopic pregnancy are reduced. Both hypertension and thromboembolic disorders can be a potential side effect from using oral contraceptive pills. Condoms and intrauterine devices will not lower her risk of ovarian cancer.
Answer:
Option C. Lipid-anchored membrane proteins always face the cell exterior.
Explanation:
Lipid-anchored proteins are proteins located on the surface of the cell membrane which are attached to lipid and embedded within the cell membrane. The lipid-anchored proteins assume a place in the bilayer structure of the membrane.