Epithelial tissue covers the entire surface of many organisms. Which term describes the structure directly below tissues in the hierarchical organization of life?

A) atoms

B) cells

C) molecules

D) organs

The adding of egg and sperm is the process known as

You are a brilliant student who has discovered a new genetic disease identified by the absence of a key enzyme involved in the Krebs cycle.

Describe the observation that led to Wegener's hypothesis?

Why is excretion necessary in living beings?

Describe one way two scientists could benefit from a disagreement with each other.

Why are some motors painted black? A) Black is a standard color code for motors. B) This prevents loss of heat from the motor. C) The motor is hotter than the surroundings and emits heat.

How can these forelimbs explain how life changes over time? Homologous structure of four different animals The illustrations show the vestigial structures of four different species that once had a function in an ancestral organism but no longer have

The extra chromosome which produces Down's syndrome is: Options: an autosome a "X" chromosome a "Y" chromosome either "X" or "Y" chromosome

Why is the. trees green

Sedimentation as a method of water purification results in what