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This question has 2 parts You obtain a sample of double-stranded DNA and transcribe mRNA from this DNA.  Then, you analyze the base composition (percentage of each base found in each strand) for each of the two DNA strands and the one mRNA strand. Numbers in the table below indicate the percentage of each base in the strand.  (Note: results may differ from the true value by about 1%; that is the best estimate that the machine you used can make.)  Question a)  Which of these strands must be the mRNA? [A]  b) Which one is the template strand (from which the mRNA was transcribed)? [B]

During which part of the cell cycle is DNA polymerase most active?

A molecule binds to a receptor on the surface of a cell membrane. A short time later the cell responds by expressing genes and synthesizing proteins. What initial process did that binding event first initiate?

You are analyzing DNA to determine which suspect was at a crime scene with a victim. You have PCR amplified short tandem repeats (STRs) from the samples and separated them via gel electrophoresis to perform “DNA fingerprinting” as follows. DNA sources are noted above each lane: Victim (Lane 1), Suspect 1 (Lane 2), Suspect 2 (Lane 3), and Crime Scene (Lane 4). DNA was loaded into wells at the top of the gel, near the lane-labels  (i.e. “Victim”, etc.).  Question:  Based on the data below, which suspect left DNA material at the crime scene? Please explain your choice, referring to specific band(s) on the gel.

During meiosis, which two processes occur that can increase genetic variation in the gametes? (Please choose all that apply.)

The buccal cavity of Nicator americanus rhabditiform larvae is long compared to Strongyloides stercoralis. 

Newer stool screening methods for common parasites (i.e. E. histolytica, G. intestinalis and Cryptosporidium) do not include:      

Red blood cells in the cytoplasm are diagnostic for E. hartmanni.

Giardia lamblia is known as the causative agent of “Traveler’s Diarrhea”.

What is the most common specimen tested for parasites?