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.
I believe the part of the cell theory you can use to refute his claim is that cells are the smallest unit of life and more importantly that all cells come from other living cells.
Answer:
Wind
Explanation:
Gymnosperms can be described as plants which lack flowers and fruits.
As they do not have flowers to attract insects like the angiosperms, they can, however, transfer their pollen through the wind. As pollen is very light in weight hence, it can be transported by the wind. The pollen transported by the wind usually results in self-pollination as the wind is not able to take the pollen to long distances.
The statement that describes the ability of the cell membrane to allow various substance to move through is that the cell membrane is preamble and allows only certain substances to pass through.
Explanation:
The plasma membrane is preamble, hydrophobic molecules and small polar molecules diffuse through lipid layer. The integral membrane proteins enable large polar molecules to pass through the membrane.
Some molecules can cross the membrane like hydrocarbons and oxygen. Whereas the large molecules like glucose and sugars cannot cross. The water pass through lipid.
Answer:
C. DNA ligase adds nucleotides to the lagging strand
Explanation:
DNA replication is the process during cell division in which DNA copies itself. DNA strands unwind with the help of helicase to initiate the process. DNA Polymerase III is responsible for prokaryotic replication and adds nucleotides in 5' to 3' direction. Since both the strands of DNA run in opposite direction their replication is slightly different. The lagging strand is also formed by DNA Polymerase III in discontinuous manner leading to formation of Okazaki fragments. DNA ligase joins these fragments once the replication process is completed.