Hiya,
Not sure how to answer this! Perhaps there is an image of the question or a lab you can attach to your question/comment so I can help you out?
Thanks.
Answer:
<u>d. the cells in primary cell cultures do not divide.</u>
A key difference between primary cell cultures and secondary cell lines is that<u> the cells in primary cell cultures do not divide.</u>
<u>hope</u><u> </u><u>it</u><u> </u><u>helped</u><u> </u><u>you</u><u> </u>
Explanation:
<em>The main difference between primary and secondary cell culture is that the primary cell culture contains the cells directly obtained from host tissue, whereas the secondary cell culture contains sub-cultured cells from primary cell culture.</em>
<span>Malthus reasoned that if the human population continued to grow unchecked, sooner or later there would be insufficient living space and food for everyone.
That is all i know sorry if this does not help
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[b] The sporangia are knob-like structures.
They are present at the top of the thread-like structures called hyphae.
They are dispersive, i.e. they are scattered by rain, wind or insects.
This is because of natural selection; since polar bears live in a rough environment, natural selection gives them more fur, more muscle, and can go longer without food