NEET Test 138

Indicator species are animals, plants, or microorganisms used to monitor changes in our environment. For example, they can tell us about the impact of pollution on an ecosystem, or how well an impaired environment is being managed or restored. Indicator species can also provide warning signals for upcoming changes or shifts to an ecosystem, such as climate change. Mollusca, Lichens, Greasewood, etc are indicator species.

Anhydrous magnesium chloride is fused with NaCl and anhydrous calcium chloride. The mixture is electrolysed at 700^∘C in the presence of an inert gas in an electrolytic cell. Magnesium is discharged at cathode. The purpose of the addition of NaCl and CaCl to anhydrous MgCl₂ is to lower to fusion temperature and make the fused mass a good conductor of electricity.

Percent ionic character for HCI molecule is 17.2%

Using electron negativity values the percentage ionic character could be calculated as:

percent ionic character =16(ΔE)+3.5(ΔE)²

where, ΔE is the electron negativity difference of two atoms.

electron negativity of H is 2.1 and for Cl it is 3.0.

So, ΔE = 3.0−2.1 = 0.9

Let's plug in this value in the formula:

percent ionic character =16(0.9)+3.5(0.9)²

percent ionic character =14.4+2.835 = 17.2

Therefore, the percent ionic character for the HCI molecule is 17.2%  ionic.

Antibiotics are compounds that are produced by an organism and inhibit the growth of another organism. They are mostly obtained from bacteria. They are used to fight the bacterial infection. However, they are not useful in viral infection. They act by either killing bacteria or preventing their reproduction.

Reproduction is the process of producing fertile offspring which look similar to parents. The individual organisms which are the same morphologically and genetically are called clones. They are formed in the asexual reproduction process. Asexual reproduction is a mode of reproduction where offspring is produced by a single parent without the requirement of gamete formation and fertilization. The offspring formed are exactly same as parents because they inherit all the chromosomes of their parent in the same pattern without any mixing.

According to Newton's law of cooling, as the rate of cooling is directly proportional to the temperature difference between the body and the surroundings

The temperature of many objects can be modelled using a differential equation. Newton's law of cooling (or heating) states that the temperature of a body

temperature between the body and its surroundings. It is a reasonably accurate approximation in some circumstances.

More precisely, let T denote the temperature of an object and T₀ the ambient temperature. If t denotes time, then Newton's law states that,

The most important biological substituted purines are adenine and guanine, which are the major purine bases found in RNA and DNA. 

In DNA, guanine and adenine base pair with cytosine and thymine respectively.

DNA replication is the process of making new DNA strand from the old one and this process is semi-conservative. Synthesis of new DNA occurs simultaneously and independently on both strands but in one direction as the DNA polymerase used in the process of elongation of the strand of DNA during replication process proceeds in the 5′→3′ direction only. The strand which is used as a template or mould to make new strand is called as parental strand. Of the two strands, the one that is continuous and occurs without stopping from one end to the other is called the leading strand, while the one that is discontinuous in that it occurs in several small chunks one after another is called the lagging strand and each short sequence is called Okazaki fragment. The replication process is bidirectional in that it goes in both ways from the point of origin of replication in the DNA.