Which molecular model describes the structure of the DNA molecule? 

 The part of a protein that determines whether translation will continue in the cytosol or at the endoplasmic reticulum is the _______ sequence. 

 Refer to the figure above showing DNA strands. Which letter represents the leading strand? 

 In prokaryotes, the region of DNA to which RNA polymerase binds most tightly is the. 

Order the four steps shown as they would occur, from beginning to end, during expression of a eukaryotic gene.(1) Pre-mRNA is processed to make mRNA.(2) Ribosomes translate the mRNA message to make proteins.(3) mRNA is transported to the cytoplasm.(4) DNA is used as a template to make pre-mRNA. 

Given the following template DNA sequence, what is the amino acid sequence? ATGTTGGACCAA. 

Which position of the codon is flexible according to the wobble hypothesis? 

List 1 source of measurement validity evidence from the Standards of Educational and Psychological Measurement AND briefly described how the evidence is collected..

 The poly A tail added to pre-mRNA. 

A researcher was interested in comparing the effectiveness of 3 types of instructional materials for teaching 1 biology concept. The instructional materials included: using text materials, video materials, text + video materials.  25 10th grade Biology students were randomly assigned to each type of instructional material for a total of 75 students.  These 75 students were volunteers  recruited from an after-school program.  Students used the method for 1, 2-hour session and were then tested using a 20 item Biology exam. What is the scale of measurement of the independent variable(s)?