At What Angles Are Section Lines Typically Drawn, and What

question 6

Essay

At what angles are section lines typically drawn, and what basic rules are followed when drawing section lines?

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Definitions:

Dipnoi

A group of fish also known as lungfish, characterized by their ability to breathe air using lungs in addition to gills.

Actinistia

A subclass of mostly extinct fish, with the modern coelacanths being the only living representatives, characterized by lobed fins.

Coelacanth

A rare order of fish that was thought to be extinct until found alive in 1938, known for its lobed fins which resemble primitive leg structures.

Sacropterygian Fishes

An ancient group of lobe-finned fishes, some of whose descendants evolved into terrestrial vertebrates.