Answer:
Analogous or convergent structure.
Explanation:
Analogous structures can be defined as structures that have similar purposes but look completely different from each other. in other words it means that they serve the same functions in different species, but they are independently evolved. Examples of analogous structures are
- wings on butterfly, bats and birds
- Fins in penguins and fish
Answer:
Histone acetylation or DNA methylation.
Explanation:
The epigenetics may be defined as the genetic phenomena that might cause mutation in the organism's genome. The DNA sequence of the organisms do not get changed in epigenetics.
This phenomena is limited whether the gene is herited from the mother ot the father. The phenomena like acetylation of histones increase the gene expression. The DNA methylation and histone deacetylation at specific residues reduces the gene expression.
Thus, the answer is histone acetylation or DNA methylation.
Answer:
(b) Voltage gated
Explanation:
The cell membrane acts as a barrier that separates two aqueous media of different composition, the extracellular and the intracellular, regulating its composition. Most of the liposoluble drugs and solutes, when not ionized, directly cross the cell membrane through a passive diffusion process, which facilitates the passage of the medium where it is more concentrated to the one that is more diluted. The difference in concentration between the two media is called the concentration gradient, and diffusion will continue until this gradient is eliminated. According to Fick's law, the speed of this process will be much faster the higher the concentration gradient and the liposolubility of the molecule and the smaller its size.
More hydrophilic molecules, such as ions, are immiscible in membrane lipids and pass through specific specific transport mechanisms. In some cases, ions pass through hydrophilic pores called ion channels, and in others a favor of their concentration gradient is transported by binding to the transporter or transporter proteins. Both transport systems are passive and therefore do not consume energy. The great advantage is that the ion channels allow the flow of ions through a much higher speed than that of any other biological system. The flow of ions through each channel can be measured as an electric current, which is capable of producing rapid changes in membrane potential.
<span>Science is a practice of gaining comprehension of the nature of materials and phenomena by gathering and evaluating evidence. A scientific study is based on an hypothesis, a theory of causality. As the body of scientific knowledge increases, the design of scientific studies is informed by previous discoveries.</span>
Answer:
homologous structures
Explanation:
Homologous structures are organs or skeletal elements of animals and organisms that, by virtue of their similarity, suggest their connection to a common ancestor. These structures do not have to look exactly the same, or have the same function.