The species is on CITES Appendix II, but its status is poorly known. The IUCN Red-List (2007, www.iucnredlist.org) classified it as Lower Risk/Least Concern
Answer:
Option A, keystone species
Explanation:
Keystone species are responsible for controlling any species from becoming dominant over all other species. The keystone species are found at the top of all the energy pyramids and food chains.
They control the explosion of population of prey and hence regulate the overall ecological diversity.
Some common example of keystone species is as follows –
Bison, prairie dog, large mammalian predators,
Hence, option A is correct
Answer:
A DNA molecule produced by combining DNA from different sources is known as recombinant DNA.
Explanation:
Recombinant DNA (rDNA) can be obtained by coupling DNA fragments from different sources, a process that is performed at the restriction site level and uses enzymes.
Once rDNA has been designed —cutting out fragments of DNA that are then reassembled— it must be brought to a specific location in the cells, to be copied and expressed, using means of transport called vectors.
<u>DNA recombination</u> is performed in biotechnology laboratories specialized in the manipulation of genetic material.
The other options are not correct because:
- <u><em>Mutant or mutated DNA</em></u><em> is a DNA molecule with an alteration of its nitrogenous base sequence
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- <u><em>Hybrid DNA</em></u><em> is a variant of recombiant DNA, in which only two DNA molecules from different sources are used.
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- <u><em>Polyploid</em></u><em> refers to cells containing the genome of different species.</em>
Answer:
Sandstone
Sandstone contains fossils of creatures such as trilobites, brachiopods, crustaceans, bryozoans and plants. Remains of land animals like mastodons and dinosaurs are much more likely to be found in sandstone.
Explanation:
thank me later
Answer:
When you get sick first time your body will produce antibodies and destroy that bacteria or virus after producing that antibody your body has memory cell specialised for that antibody so you won't get sick everytime when you get that specific type of antigen
