Understanding Chemical Reactions and Equilibrium in Systems

1. If there is a chemical reaction within a system, this system cannot be a closed system.

False – A closed system does not exchange matter with its surroundings. Mass is conserved in a chemical reaction. Therefore, it is possible that a reaction happens within a closed system as long as no mass is exchanged with its surroundings.

2. If there is a chemical reaction within a system, this system cannot be in equilibrium.

False – It is possible for a system to be in equilibrium even if a chemical

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Molecular Probes: Types and DNA Library Screening Techniques

Molecular Probes: Definition, Types, and Library Screening

A probe is a single-stranded sequence of DNA, RNA, or a specific protein/antibody that is labeled with a detectable marker (radioactive, fluorescent, or chemical tag) and used in molecular biology to detect the presence of a specific, complementary target sequence in a complex mixture.

Types of Probes

Probes are generally classified by their chemical nature and intended target:
  • DNA Probes: These are single- or double-stranded DNA sequences used
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Cellular Energy and Enzyme Function: Biochemistry Fundamentals

Cellular Life and Open Systems

Living cells function as open systems, constantly exchanging matter and energy with their environment.

Key System Definitions

  • Open System: A system that continuously exchanges matter and energy with its surroundings, transforming and storing energy to perform biological activities.
  • Equilibrium System: A system where the values of certain predefined variables are maintained over time within a range of tolerance.
  • Dynamic Balance of Flows: The typical state of living organisms,
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Genetic Modification and Uses of Transgenic Animals

Understanding Transgenic Animals

Transgenic animals are animals with a modified genome. A foreign gene is inserted into the animal’s genome to alter its DNA. This method is performed to improve the genetic traits of the target animal.

Initially, the improvement of genetic traits was achieved through selective breeding methods. In this process, animals with desired genetic characteristics were mated to produce offspring with improved traits. Since this technique was time-consuming and expensive, it

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Southern Blotting Technique: DNA Detection Principle and Procedure

Southern Blot Definition and History

Southern Blotting is a laboratory technique used for the identification of specific DNA sequences in DNA samples. It involves the transfer of DNA fragments, separated by electrophoresis, onto a membrane for immobilization and subsequent identification.

Southern Blotting has been adopted as a routine procedure for the analysis of DNA samples across various applications.

The technique was discovered by Edwin Southern, after whom it was named. This methodology later

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Core Principles of Pharmacology and Drug Action

Introduction to Pharmacology

Pharmacology is the branch of medicine and biology that focuses on the study of drugs and their effects on living organisms. It is a multidisciplinary field that combines principles from biology, chemistry, medicine, and toxicology. Pharmacology helps us understand how drugs work, how they are metabolized in the body, their therapeutic effects, potential side effects, and the mechanisms behind these actions.

Core Concepts in Pharmacology

Drug Definition

A drug is any substance

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