All vertebrates have a(n)
a. exoskeleton
c. proboscis
b. swim bladder
d. endoskeleton

Which statement is true about the cell theory? a) it is well-supported by evidence. b) it is unchangeable and permanent.

How does the molecular clock work? a. it analyzes the brain functionality of two different species.b. it examines and compares the physical characteristics of two different species.c. it illustrates relationships between two different species.d. it compares the number of mutations that exist in the dna of two different species.

Will mark brainliest. (20 points) many have pigments structures known as eyespots that detect direction of light. a. b. archaebacteria c. protists d. none of the above