What are two main types of posttranscriptional modifications that take place in the mrna of eukaryotes? the excision of the introns and the addition of a 7-mg cap to the 3' end. the addition of a poly-t sequence at the 5' end of the gene and the addition of a poly-u tail at the 3' end. the addition of a 7-mg cap at the 5' end of the transcript and the addition of a poly-a sequence at the 3' end of the message. the addition of a poly-a sequence at the 5' end and the addition of a 7-mg cap at the 3' end of the rna transcript.

Researchers randomly divide participants into groups. each group takes a different amount of omega-3 fatty acid supplements daily for a month. one group receives a placebo. the researchers measure the impact on cholesterol levels in the blood. what is the purpose of random assignment in this experiment? a, to produce treatment groups with similar characteristics b, to ensure that all people with high cholesterol have an equal chance of being selected for the study c, to increase the accuracy of the research results and prevent skewness in the data

Which of the following does not describe a physical property of iron? a iron is silvery-white or gray in color. b iron has a boiling point of about 3,000°c. c iron is a magnetic element . d iron and sulfur react to form iron sulfide.

Theories basic to all of the life sciences include the germ theory of disease. theory of evolution by natural selection. o two of these answers are correct none of these answers are correct o cell theory.