Answer:
Rosalind's x-ray showed that the ladders of nucleotides were inside a double helix.
Watson and Crick built models with the ladders on the outside.
Answer:
The correct answer is option D.
Explanation:
In the presence of SDS single band appeared, while in the absence of SDS two bands appeared. SDS or sodium dodecyl sulfate refers to an anionic detergent, which combines with amino acid side chains providing the protein a net negative charge. It dissociates the non-covalent bonds.
In SDS-PAGE, the separation of proteins takes place on the basis of their molecular weight. Options A and B are incorrect as only in the presence of SDS, the separation of protein subunits takes place. Option C is also incorrect as a protein containing distinct molecular weight cannot show single band.
Option D is correct as the presence of SDS supplements a bunch of negative charges to the protein, thus, charge is not the factor. Therefore, the proteins are distinguished on the basis of the molecular weight. Thus, identical molecular weight demonstrates a single band. In the non-presence of SDS, charge performs a function along with the molecular weight, therefore, two bands appear.
Answer:
(3) could be mistaken for food by some species, working their way up the food chain
Explanation:
Microbeads, such as other microplastics, can affect wildlife in many ways, but mostly by
- Ingestion
- Introduction and transference in the trophic web
- Interaction with other contaminants
- Microinvertebrates, bacteria, and viruses colonize these microplastics and can be transported long distances.
Organisms like mollusks, crustaceans, fishes, birds, turtles, among many others, might confuse these elements with food and eat them. Microbeads might float or accumulate in sediments and be ingested by different benthonic species. The ingestion of microbeads by inferior links in the trophic web means a direct entrance in the trophic web where many superior links are affected too while feeding with already contaminated prey.
The ingestion of microbeads can cause a significant impact on the growth, development, and reproduction of freshwater and seawater species.
Microbeads, like other microplastics, characterize for their durability in time and resistance, which means that the ones that are already in the oceans and rivers will last there for centuries.
Gene. A segment of a DNA molecule that codes for a particular protein and determines the traits of the individual. A gene is the basic unit of heredity in a living organism
Hope it helps!
