What is the name of the openings in the abdominal exoskeleton of insects?

Cell walls of fungi are made out of:

The main difference between gymnosperms and angiosperms is that

What are the cell types that make the nerve tissue?

The products of cellular respiration are:

Which bony fish gave rise to tetrapods?

The following are types (categories) of connective tissues, EXCEPT:

The type of muscle tissue which produces slow, sustained involuntary contractions, is called:

A plant with parallel veins, fibrous roots, and scattered vascular bundles in the stem is

A circulatory system in which blood is confined within continuous vascular network with a pumping heart is called: