Answer:
A) A transgene integrated into a heterochromatic region of the genome.
Explanation:
This is most likely the reason why the transgene is not expressed in the fifth cell line. It is likely that the transgene was integrated into a heterochromatic region of the genome. Heterochromatin consists of genetically inactive satellite sequences, and many of these are repressed to various extents. Moreover, because this is a tightly packed form of DNA or condensed DNA, it is inaccesible to polymerases and thus not transcribed.
Answer:
<u><em>All of the above.</em></u>
Explanation:
1. Their watertight skin minimizes moistures loss: <em>Reptiles have a reputation that they are “slimy” when we touch and hold them; however, they have dry skin, which has even fewer glands than mammals or amphibians. The main special feature of their skin is that the epidermis is heavily keratinized with a layer, which also prevents water loss.</em>
2. Amphibians must lay eggs in water or in moist soil to reduce moisture loss: <em>Because amphibian eggs don't have an amnion, the eggs would dry out if they were laid on the land, so amphibians lay their eggs in water.</em>
3. Reptile egg shells are harder than amphibians' eggs: <em>Reptile eggs are coated with a leathery or brittle coating, and the animals that hatch from them are miniature versions of the full-sized animal parent. In contrast, amphibian eggs are transparent and jelly-like. The animals that hatch from them still must go through metamorphosis.</em>
<u><em>Hope this helps you have a better understanding:) !!</em></u>
Eukaryotes are organisms whose cells have a nucleus enclosed within a nuclear envelope.
Two factors contributed to the success of the pteridophytes: the extreme miniaturization of the gametophytic generation and an important development of the sporophytic generation (development of the tree forms).
Pteridophytes are a group of plants that peaked in the Carboniferous (-300 million years). It is the first great terrestrial plant civilization. These plants would have appeared in the Devonian -400 million years ago, perhaps from certain primitive terrestrial plants which, unlike bryophytes, would have favored the diploid generation on the haploid generation.
Particularly well adapted to terrestrial life, they have created, thanks to the development of tree forms, immense forests whose fossilization is at the origin of coal deposits.
Pteridophytes are at the origin of an evolutionary lineage based on the extreme miniaturization of gametophytic generation and an important development of sporophytic generation, leading to all tracheophytes including current flowering plants. Pteridophytes are well adapted to terrestrial life, however fertilization still requires the presence of water since male gametes are swimmers.
