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

You cross two plants that have pink flowers. The F1 offspring include mostly plants with pink flowers, some plants with red flowers and some plants with white flowers. Your goal is to have as many pink-flowered plants in the F2 generation as possible. Which F1 plants would you cross to achieve this goal?

Which of the following processes produces the most ATP?

Optional extra credit (2 points)! The SARS-CoV-2 virus responsible for the current COVID-19 pandemic gains entry to epithelial cells especially of the respiratory and oral passageways by binding to angiotensin-converting enzyme 2 (ACE2) found on their surface. The structure of ACE2 is shown below. 1) Consider the ribbons forming coils. What are these particular structures called? 2) What level of protein structure (i.e., primary, secondary, tertiary, or quaternary) are these structures considered, and what type of bonds are primarily responsible for the formation of these structures? Photo credit: Emw – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=8761587

When producing unfertilized eggs, female fruit flies deposit mRNA coding for the Bicoid protein at the anterior (head and upper body) side of the egg. Following fertilization, a concentration gradient of Bicoid develops that ranges from high concentration of the protein at the anterior end to a low concentration at the posterior (abdomen and rear end) end. Where Bicoid is present, anterior structures form; in its absence, posterior structures form. Bicoid therefore plays a critical role in the development of structures in the fruit fly. Following fertilization, how is Bicoid produced?

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.)