Questions & Answers about La profesión es importante.
Because profesión is a feminine noun in Spanish, so it takes the feminine article la.
A very useful pattern is that nouns ending in -ión are usually feminine:
- la profesión
- la nación
- la decisión
So this is something worth memorising as a general rule.
The accent mark shows where the stress goes: pro-fe-SIÓN.
Without the written accent, Spanish stress rules would make you stress the wrong syllable. Since profesión ends in -n, Spanish would normally stress the second-to-last syllable, so the accent mark is needed to show that the stress is actually on the last syllable.