He could hold his breath for a long time but then he had some difficulties to _______ normally.

Most dogs have 319 _______ but this may vary depending on the breed. 

In vitro ____________________ is the joining of a woman's egg and a man's sperm in a laboratory dish

Turtles may take between 3 and 7 days to dig their way out the egg and finally ________.

Spring is usally birds' ______ season.

______ is actively injected via a bite or sting. Poison is a toxin that gets into the body via swallowing, inhaling or absorption through the skin.

How long can we ________ without oxygen?

After five to ten minutes of not breathing, you are likely to develop serious and possibly irreversible brain damage.

A reptile can only survive at a ____________ of 0 C° to 40 C°. Reptiles and amphibians tend to survive well in cooler environments

I just can't stand walking on the _______ wearing sneakers. It's simply annoying.

Dolphin's skin is very ___________! It feels as if it was made of plastic or rubber.

Removing a bee's ________ can be difficult but you can always use tweezers.

I broke a glass and as I was picking the pieces up, I cut myself. It was too _______.