A dna molecule has a unique design that resembles a spiral staircase. scientists call this design a a. double helix. b. spiral structure. c. double nucleotide. d. spiral purine.

True or false: microorganisms in the water provide nutrients for coral, sponges, and some fish.

3. Haploid reproductive cells.

1. By examining the fin of a primitive fish, scientists have found similarities in bone structure to that of modern day reptiles, birds, and mammals. What type of evidence does this describe?

Homologous structures can be best be described as structures that ... are so similar that they imply a common ancestor have the same structures and functions have the same structures had a function in an ancestor but don't have that function today

Which of these is not a response to internal stimuli? breathing hard when exercising because of a drop in oxygen levels eating when hungry wearing sunglasses to protect eyes from UV rays drinking when thirsty

We summarize natural selection as "survival fittest". what factor "selects" the fittest organisms in natural selection?

Hypothesis may arise from what

What kind of dna replication error will result in changing an amino acid codon to a stop codon?

Which insulates various internal organs from the stresses of body-wall movement and bathes them in a liquid through which nutrients and waste products can diffuse?

In which part of the body would melanoma develope