completed question'
.....culturing viruses that requires a human host
Answer:
Diploid cell culture lines, developed from human embryos, are widely used for culturing viruses that require a human host
Explanation
Viruses can not thrive in a non-living host or artificial media.They are intracelular parasites which needed living host to replicate . Cultures lines from Human embryo in are therefore used for culturing viruses of human host, so that its mode of replication and gene expression can be studied, and therefore its virulence can easily be studied.
This method have the advantage that;
1.there is no need to make use of the whole animal rather,on a tiny tissue needed can be isolated for culture.
2. the cells growth is continuous,and can be preserved in liquid Nitrogen and renew for future culture
3. cells can be grown in different containers, with ability to decide the number of cells needed.
Temperature is kept at optimum for human in the culture at 37 degree centigrade, nutrients are provided, NaHC03 as buffers for C02, and the medium is humidified.
Answer:
This means that the two separate rocks were once part of one piece of rock. These layers got separated most probably by continental drift as a result of tectonic plate movements. An example of such a fossil is the Mesosaurus, a freshwater crocodile-like reptile, that is found in Southern Africa and Eastern South America continents- that means they were once one land mass.
The environment in these two separate layers would most likely be different. As the layers drift apart from each other , they drift across latitudes that are determinants of climate in a region. Therefore, even the organisms in these two rock layers will evolve differently (even though they will share a common ancestor) in adaptation to respective environments – this is called allopatric speciation.
Answer: (C) The production of tissue-specific proteins.
Explanation:
The cell differentiation is the process in which the cell change from one cell place to another place. It basically occur due to the process of gene expression.
The cell differentiation involve the production of the specific tissue protein known as muscle actin. In cell differentiation, the pluripotent stem cell basically go in the specific differentiation level and then reach in the state of fully differentiation.
The fully differentiation produced a specific function that the production of the protein. Therefore, option (C) is correct.