Explanation

Restriction enzymes are molecular scissors that cut DNA at specific sequences, a critical tool in molecular biology for gene cloning and DNA manipulation.

Explanation

The biogenetic law, also known as recapitulation theory, was proposed by Ernst Haeckel.

It suggests that the development of an organism (ontogeny) mirrors the evolutionary development of the species (phylogeny).

Explanation

Trilobites are an extinct group of marine arthropods that lived during the Paleozoic Era.

They are one of the earliest known groups of arthropods.

Explanation

The Paleozoic Era was a time of significant diversification of life, marked by the Cambrian Explosion, during which many major groups of animals first appeared in the fossil record.

Explanation

Gymnosperms are plants with "naked seeds," meaning their seeds are not enclosed within a fruit.

This group includes conifers like pine trees.

Explanation

The mass extinction event that led to the demise of dinosaurs occurred at the end of the Cretaceous period, approximately 66 million years ago.

Explanation

Enzymes act as biological catalysts, speeding up chemical reactions in the body without being consumed in the process.

They are essential for various physiological processes, including digestion and metabolism.

Explanation

Divergent evolution occurs when two or more species evolve from a common ancestor and adapt to different ecological niches, leading to increased differences between them over time.

Explanation

Calcium is the most abundant mineral in the human body, making up 1.5 to 2% of the total body weight.

Approximately 1,200 g of calcium is present in the body of an adult human; more than 99% of that amount is found in bones.

Explanation

Arachnids, such as spiders and scorpions, are distinguished by having eight legs, a characteristic feature of this class.