To be honest, I wasn't sure whether to make a guide for this or not since you can get most of the secrets on your own, but I decided to make it anyway since the game might be difficult to non-medical students. I even gave up on trying to get some info on google to answer the questions halfway through the game and randomly chose the answer that I thought was correct instead.

Some info before you read the guide:

• Some objects (like pond and flowers) require you to inspect the same or similar object more than once. If you didn't get gold from inspecting it, try to do it several times, to other similar objects if possible.
  
• You won't get hurt if you answer the questions wrong. I don't even think you can die unless if you stepped on the "poisonous" tile in the last area.
  
• You can't use gold for anything except to buy some "useless" items near the end of the game, but I found 222 gold in total. I'm not sure if there are more.

- Inspect all of the flowers to get gold.
- Inspect the pond several times to get gold.
- Exit the area.

- Inspect the nearby pond to get gold.
- Head to the castle.

- Speak to the fairy until you get gold.
- Inspect all of the pots in the area to get gold.
- Talk to the king.
- Exit the area and head to the town.

- Inspect the flower near the entrance to get gold.
- Inspect the box on the northwest corner (west of the house with blue roof) to get gold.
- Inspect the flower east from the well to get gold.
- Inspect the log with flower on the southeast corner (south from Ben) to get gold.
- Climb the ladder and save before going east.

Enemy: Scary Zombie
Choose "On his trachea's inner lining!".

- Inspect the skeleton to get gold.
- Save and head east.

Enemy: A pair of slimes
Choose "Plantar".

- Head east.
- Inspect the barrel west from the skeleton in the middle to get gold.
- Save before reaching the red floor.

Enemy: A Horrifying Vampire
Choose "His Occipital Lobe!".
For the quiz after that, choose O-.

- Exit the wall and head to the next area.

- Save and inspect the grave.

Enemy: A Spooky Ghost
Choose "Attack his Electrolytes!".

- Save and inspect the tree east of the two barrels to get gold and a boss fight.

Enemy: A Hidden Minotaur
Choose "Keratin".

- Talk to the chef and accept his offer.
- Inspect the boat and head north.

Enemy: A Flying Dragon
Choose "Lymphatic System".

- Inspect the pond on the island to get gold.
- Report back to the chef, exit the area, and head to the next area.

- Inspect the trees to get gold.
- Inspect the flower pot to get gold.
- Talk to the lady near the lake and answer "Troponin".
- Inspect the lake several times to get gold.
- Enter the building.

- You can buy some items from the seller if you want. It won't do anything though.
- Talk to the bunny girl and answer "Somatic Nerve".
- Exit the area and head to the next area.

- Talk to the woman.
- Save before the final boss.

Enemy: The Skeleton Lord
Choose "His Mandible".

Test answers:
1. Organism.
2. Hormones.
3. Blood Clotting.
4. No.
5. Hyperpolarisation.
6. Connective Tissue.

That's it! The game can be finished in less than 1 hour so it's no surprise that the guide is short. Do let me know if there's something I missed. Thanks for reading!