Question 1: Define a nucleotide and explain its role in DNA structure.

Answer: A nucleotide is the basic unit of DNA, composed of a sugar, a phosphate group, and a nitrogenous base; it forms the building blocks of DNA strands.

Question 2: What are amino acids, and why are they important in living organisms?

Answer: Amino acids are organic compounds that combine to form proteins, which are essential for growth, repair, and enzyme functions in living organisms.

Question 1: Calculate the molecular weight of the amino acid Glycine (C2H5NO2). Use atomic weights: Carbon (12 g/mol), Hydrogen (1 g/mol), Nitrogen (14 g/mol), Oxygen (16 g/mol).

Answer: 75 g/mol

Question 2: If a DNA strand has 300 adenine (A) bases, how many thymine (T) bases are present in the same strand, assuming complementary base pairing?

Answer: 300 thymine bases

Question 1: Describe a simple experiment to extract amino acids from a protein solution. Include the main steps and safety precautions.

Answer: The experiment involves hydrolyzing the protein with acid, then using chromatography to separate amino acids. Safety precautions include wearing gloves, goggles, and working in a well-ventilated area to handle acids and chemicals safely.

Question 2: Identify at least two variables that need to be controlled during DNA extraction in the laboratory.

Answer: Temperature and pH levels need to be controlled to ensure effective DNA extraction.

Question 1: A sample of DNA was analyzed, and it was found to contain 20% cytosine (C). Assuming the DNA is double-stranded and has equal amounts of C and G, what percentage of the DNA is made up of guanine (G)?

Answer: 20%

Question 2: In a lab, a solution containing 50 mg/mL of amino acids was prepared. How much amino acid is present in 10 mL of this solution?

Answer: 500 mg

Question 1: Explain how knowledge of amino acid sequences can be used in developing personalized medicine.

Answer: Knowing amino acid sequences allows scientists to understand genetic variations and mutations, enabling the development of targeted treatments tailored to an individual's genetic makeup, thereby increasing treatment effectiveness and reducing side effects.

Question 2: Identify a modern industry that utilizes DNA technology and describe its application.

Answer: Forensic science uses DNA fingerprinting to identify individuals involved in crimes.