Abacterium closely associated with humans is known to be responsible for gastric ulcers and
stomach cancers. the genus of this bacterium is:
a. heliothrix
b. helicobacter
c. herpetosiphon
d. histophilus
e. herbaspirillum

Which conditions are necessary for natural selection to occur? select all of the answers that apply. a. inheritable adaptations vary among individuals. b. the population size is increasing. c. more individuals are born than can survive. d. fitness varies among individuals. e. the environment changes suddenly and drastically.

Based on anatomical similarities, to which modern animal is dr. digger’s creature most closely related?

You have just sequenced a new protein found in mice and observe that sulfur-containing cysteine residues occur at regular intervals. what is the significance of this finding? it will be important to include cysteine in the diet of the mice. cysteine residues are required for the formation of α helices and β pleated sheets. cysteine residues are involved in disulfide bridges that form tertiary structure. cysteine causes bends, or angles, to occur in the tertiary structure of proteins.