Leucine is an essential amino acid that must be obtained through diet.

Butterflies are insects and belong to the class Insecta, characterized by having three pairs of legs and usually two pairs of wings.

Jellyfish are examples of cnidarians, which are known for their stinging cells called cnidocytes.

Earthworms belong to the phylum Annelida, which is characterized by segmented bodies.

Phylum Chordata includes animals that possess a notochord at some stage of their development, such as sharks.

A climax community is a stable and mature ecological community that has reached a steady state.

A food web is a complex network of feeding relationships that illustrates how different organisms are interconnected in an ecosystem.

A trophic level refers to the position an organism occupies in a food chain or food web, indicating its role in energy transfer.

Adaptive radiation refers to the rapid evolution of many species from a common ancestor, often in response to new environmental opportunities.

Genetic drift refers to random changes in allele frequencies in a population, often having a more significant effect in small populations.

In liquids, particles are close together but can move past each other, allowing liquids to flow.

According to the kinetic molecular theory, gas particles are in constant random motion.

'Survival of the fittest' refers to the idea that those individuals best adapted to their environment are more likely to survive and reproduce.

In gases, particles are far apart and move freely, allowing them to fill the container they are in.

Adaptive radiation refers to the rapid evolution of many species from a common ancestor, often in response to new environmental opportunities.

Carrying capacity refers to the maximum population size that an environment can sustainably support.

In an evolutionary context, 'fitness' refers to an organism's reproductive success and its ability to pass on its genes to the next generation.

Nucleic acids, such as DNA and RNA, carry genetic information.

Butanoic acid has a pungent odor, often described as rancid butter.

Butanoic acid has the highest boiling point due to its longer carbon chain and greater molecular weight.

Adding a catalyst speeds up the rate of both the forward and reverse reactions equally, thus it does not affect the position of equilibrium.

According to Le Chatelier's principle, increasing the concentration of a reactant (O2 in this case) will shift the equilibrium to the right, favoring the formation of products.

Reptiles are known for having scales that protect their bodies and reduce water loss.

Kingdom is the most inclusive classification among the options provided, encompassing a large group of related organisms.

[CoCl2(NH3)4]+ can exhibit geometrical isomerism due to the different arrangements of ligands around the cobalt ion.

[Fe(H2O)6]3+ has unpaired electrons, making it paramagnetic, while the others have all paired electrons.

Dimethylamine is a secondary amine as it has two alkyl groups attached to the nitrogen atom.

2-Propanol can be oxidized to form acetone, which is a ketone.

Nitrobenzene can be reduced to aniline using reducing agents like Sn/HCl.

Nitrous acid can be used to distinguish between primary, secondary, and tertiary amines, as it reacts differently with each type.