Biology Chapter 2 Flashcards

Nervous System and Chemical Processes

• Sodium (Na) is essential for the proper conduction of nervous impulses.
• Phospholipids are partially polar and partially non-polar in nature, playing a critical role in cell membranes.
• Genetic information is encoded in DNA through the sequence of nucleotides.

Proteins and Their Functions

• Proteins can be denatured by heat or acidity; their function relies on their three-dimensional shapes.
• Collagen is the most abundant protein in the body, providing structural support.
• Enzymes, which are proteins, function as biological catalysts, but they do not carry genetic information.

Carbohydrates and Energy Storage

• Carbohydrates are stored in the body as glycogen, primarily in the liver and muscles.
• Neutral fats consist of a 3:1 ratio of fatty acids to glycerol.

Enzymes and Reactions

• Coenzymes are organic molecules derived from vitamins, enhancing enzyme activity.
• Chemical reaction speed is influenced by temperature, concentration, and catalysts but not by the mere presence of carbon.
• In redox reactions, both decomposition and electron exchange occur; the electron acceptor is oxidized, while the donor is reduced.

Acids, Bases, and pH

• A pH of 2 indicates a highly acidic solution.
• Human blood typically maintains a pH range of 7.35 to 7.45.

Elements and Isotopes

• The four elements making up roughly 96% of the body are carbon, oxygen, hydrogen, and nitrogen.
• Isotopes differ in atomic mass but have the same atomic number and exhibit varying neutron counts.

Molecular Structures

• Chemical bonds determine molecular stability, with hydrogen bonds influencing the three-dimensional structures of proteins and nucleic acids.
• The formula C6H12O6 represents a molecule with 6 carbon, 12 hydrogen, and 6 oxygen atoms, indicating a glucose structure.

Types of Solutions

• Blood is an example of a suspension, while colloids are mixtures that do not settle but scatter light.
• Solutions consist of a solvent in larger quantities and solute in smaller amounts.

Fat-Soluble Vitamins

• Vitamin D is produced in the skin upon UV exposure and is crucial for bone growth.

Amino Acids and Proteins

• A polypeptide chain consists of 25 amino acids.
• Fibrous proteins like collagen and elastin are vitamin-derived and generally insoluble in water.

Chemical Reactions and Synthesis

• Amino acid bonds reflect synthesis reactions, whereas time does not influence reaction rates significantly.
• Dipeptides form by the condensation of amino acids.

Unique Molecular Characteristics

• Dipoles are polar molecules characterized by unequal sharing of electrons.
• The presence of an unaccounted ion results in the creation of an anion when ionically bonded.

Colloids and Mixtures

• Examples of colloids include Jell-O and cytosol, both demonstrating scattering properties.
• Colloids differ from true solutions due to visible scattering and the absence of sedimentation.

Minerals and Heavy Metals

• Iron is recognized as a heavy metal naturally found in the body, integral for various biological processes.
• Water (H2O) is not considered an electrolyte, despite being vital for life.