A perihelion is the point in the orbit of a planet or other celestial body when it's closest to this
As opposed to spontaneous generation, it's the theory that life originates only from living organisms
This layer of fat helps maintain a whale's body temperature at 93-99 F., & that's nothing to cry over
When you "make a muscle" in your arm, you contract this 2-headed muscle
The leaves of a fern are commonly called this, from the Latin for "foliage"
It's secreted by the liver, stored in the gallbladder & released into the duodenum after eating
The patellar reflex is an involuntary reaction of this joint
Paramecia & amoebas are types of this single-celled organism
In 1686 this English astronomer became the first to publish a meteorological chart
Most of a cell's water passes through the plasma membrane by this process