Helper T cells become activated by interacting with antigen presenting cells. and the second blank space is either cytotoxic t cells or B cells
Answer:
Because DNA polymerase can synthesize DNA strands in 5' to 3' direction only.
Explanation:
The 5' end of one DNA strand is present opposite to the 3' end of the other strand. But DNA polymerase enzyme can elongate the primers in 5' to 3' direction only. Formation of a phosphodiester bond between the existing nucleotide and the incoming nucleotide requires the free 3'OH. This 3' OH serves in the nucleophilic attack during the formation of the bond.
Therefore, the lagging strand is synthesized discontinuously in the form of short DNA fragments. These are called Okazaki fragments. Primers are formed for short distances which in turn are elongated by DNA polymerase to form the Okazaki fragments. On the other hand, the synthesis of the leading strand occurs continuously in the same direction in which the replication fork moves.
Answer: dandelion is consumed by bees, grasshoppers, and butterflies.
The pectoral muscles are found on the anterior chest wall (thoracic wall) of a pig. Three pectoral muscles are:
1. Pectoralis major- the most superficial muscle in this region.
2. Pectoralis minor- the muscle that is below the pectoralis major
3. Serratus anterior- the muscle that is adjacent to the chest wall
Explanation:
(a) After vis friends comforted him he went back to school.
(b) No. HIV can only be caught by another person of they come in contact with your blood or through sexual intercourse. So it is not possible for others to become infected if they didn't come in contact with the person's blood or have unprotected intercourse. There is no reason for a HIV+ve person to isolate themself from the outside world. They are people just as we are but they only have something that can cause them to be really sick.
