Answer:
The body naturally responds by rejecting the new organ because it is identified as a foreign object. Doctors use tissue typing to measure the compatibility of the antigens in the organ to that of the recipient. Another way doctors make sure the organs are accepted is through immunosuppressants that make the immune system does not attack the organ.
Explanation:
must include:
body rejects transplants because it recognizes them as foreign
lymphocytes attack the new organ
tissue typing measures antigens on tissue donor organ for compatibility
immunosuppressants disrupt the replication process of lymphocytes that produce antibodies and makes the immune system less effective
A film of water covers the gametophyte
The answer is d b/c smaller cells will have greater surface area to volume ratio
Answer:
The correct statement concerning the cell membrane lipid molecules is that "energy is not expended during diffusion" (Option d)
Explanation:
Biological membranes are formed by two lipidic layers arranged with their hydrophilic polar heads facing the exterior and the interior of the cells, and their hydrophobic tails against each other. Membranes are fluid, which means that molecules that form it have the capability to move through it.
Lipids can easily change places with other neighbor lipids by <u>lateral diffusion</u> in the same layer. This is passive diffusion, which means that it does not need energy to happen.
Lipids can also diffuse transversally to the other layer, but this kind of movement is not as easy as lateral diffusion.
There are also other lipidic movements as rotational diffusion that imply the rotation of the molecule.
Through this lipidic bilayer, there is also a passive transport of some particles from one side of the cell to the other which happens because of concentration differences.