What is the name of the regulatory region in a gene that controls its expression?

Correct Answer: C

Rationale: A) Exon: Exons are the coding regions of a gene that are transcribed into mRNA and eventually translated into proteins. Exons do not regulate gene expression. B) Intron: Introns are non-coding regions of a gene that are removed during RNA processing and do not play a direct role in controlling gene expression. C) Promoter: The promoter is a regulatory region located at the beginning of a gene that initiates the process of transcription by binding transcription factors and RNA polymerase. It plays a crucial role in controlling gene expression. D) Enhancer: Enhancers are regulatory regions that can be located far from the gene they regulate and can increase the transcription of a gene. While enhancers are important for gene expression, the specific region that controls gene expression is the promoter. Therefore, the correct answer is C) Promoter, as it is the regulatory region in a gene that controls its expression by initiating transcription.

Correct Answer: A

Rationale: Deamination is the correct answer. It is the process of removing an amino group from a molecule, like converting ammonia (NH3) into a less toxic form such as urea. Ammonia, a byproduct of protein digestion, must be converted into a less toxic form for excretion. Deamination is a crucial step that mainly occurs in the liver through the urea cycle. Transamination involves transferring an amino group from one molecule to another, not removing it as in deamination. Decarboxylation is the removal of a carboxyl group from a molecule, and hydrolysis is the breakdown of a compound by adding water.

Correct Answer: B

Rationale: The recommended daily fluid intake for adults is typically around 2 liters, which is equivalent to about 8 cups or half a gallon. This amount can vary depending on factors such as age, gender, weight, activity level, and climate. Staying adequately hydrated is essential for overall health and helps maintain proper bodily functions, such as regulating body temperature, aiding digestion, and transporting nutrients and oxygen throughout the body. Drinking enough fluids also helps prevent dehydration, which can lead to symptoms like fatigue, headaches, and dizziness. Choice A, 1 liter, is insufficient and may not meet the body's hydration needs, while choices C and D, 3 liters and 4 liters, respectively, are excessive for most adults and could potentially lead to overhydration, which may have negative health consequences. It's important to note that individual fluid needs may vary, so it's always best to consult with a healthcare provider for personalized recommendations.

Correct Answer: C

Rationale: Activation energy is the energy required to break a chemical bond and initiate a chemical reaction. It is the minimum amount of energy needed to start a chemical reaction by breaking bonds in the reactant molecules. Kinetic energy (option A) is the energy of motion and is not directly related to breaking chemical bonds. Potential energy (option B) is stored energy that can be converted into other forms of energy but is not specifically about breaking chemical bonds. Bond energy (option D) refers to the energy required to break a particular chemical bond in a molecule and is not the general term for the energy needed to break any chemical bond. Activation energy is crucial in determining the rate of a chemical reaction as it affects the probability of reactant molecules colliding with sufficient energy to surpass the energy barrier and form products.

Correct Answer: C

Rationale: Distillation is the process of separating a mixture based on the different boiling points of its components. During distillation, the mixture is heated to vaporize the component with the lowest boiling point first. The vapor is then cooled and condensed back into a liquid, allowing for the collection of fractions with different boiling ranges. This technique is effective for separating components that have significantly different boiling points. Filtration (Choice A) is a method used to separate solids from liquids or gases using a filter medium. Chromatography (Choice B) is a technique used to separate components of a mixture based on their differential affinities to a stationary phase and a mobile phase. Centrifugation (Choice D) is a process of separating particles from a solution based on differences in size, shape, density, and viscosity by spinning the mixture at high speeds.