BCS 205 FA23 Final Exam Study Guide
Acid-Base Chemistry
Definitions and Characteristics
Acids are substances that release hydrogen ions (H+) in solution, resulting in a pH of 0.0-6.9.
Bases are substances that release hydroxyl ions (OH-) in solution, resulting in a pH of 7.1-14.0.
Common examples of acids include hydrochloric acid (HCl) and lactic acid, while bases include
sodium hydroxide (NaOH).
pH Scale and Its Importance
The pH scale ranges from 0 to 14, with lower values indicating acidity and higher values
indicating alkalinity.
A pH of 7 is considered neutral, which is the pH of pure water.
The pH of biological fluids is crucial for enzyme activity and metabolic processes.
Biomolecules and Their Functions
Comparison of Biomolecule Sizes
Nucleic acids are the largest biomolecules, followed by proteins, lipids, and carbohydrates (e.g.,
glucose).
This size hierarchy is important for understanding their roles in cellular functions and structures.
Energy Production from Biomolecules
Carbohydrates yield 36-38 ATP from glucose, while lipids yield approximately 144 ATP from
triglycerides (TAG).
Proteins yield about 36 ATP, but their primary role is not energy production.
Roles of Biomolecules in the Human Body
Carbohydrates provide immediate energy (ATP).
Lipids serve multiple functions: energy storage, temperature regulation, cell membrane
structure, hormone production, and protection.
, Proteins are involved in nearly all biological processes, including enzyme activity, immune
response (antibodies), and cellular signaling.
Protein Structure and Function
Structural Levels of Proteins
Primary structure: the sequence of amino acids in a polypeptide chain.
Secondary structure: local folding patterns such as alpha-helices and beta-sheets.
Tertiary structure: the overall 3D shape of a polypeptide, formed by interactions between R
groups.
Quaternary structure: the arrangement of multiple polypeptide chains into a functional protein.
Amino Acid Bonds and Polarity
Amino acids are linked by peptide bonds, which are covalent and polar.
The polarity of bonds affects solubility and transport across cell membranes.
Non-polar molecules can diffuse through membranes, while polar and ionic molecules require
transport proteins.
Human Physiology and Homeostasis
Transport Mechanisms
Active transport requires ATP and moves substances against their concentration gradient.
Passive transport occurs without energy expenditure, moving substances down their gradient.
Examples include diffusion, osmosis, and facilitated diffusion.
Fluid Tonicity and Cellular Response
Hypertonic solutions cause cells to shrink (crenate) due to water loss.
Hypotonic solutions lead to cell swelling and potential lysis due to water influx.
Isotonic solutions maintain cell size and shape, achieving equilibrium.
Menstrual Cycle Milestones
Day 1 marks the start of menstruation, while Day 14 indicates ovulation, characterized by a
spike in luteinizing hormone (LH) and estrogen.
The egg takes approximately 7-10 days to travel from the ovary to the uterus.
Acid-Base Chemistry
Definitions and Characteristics
Acids are substances that release hydrogen ions (H+) in solution, resulting in a pH of 0.0-6.9.
Bases are substances that release hydroxyl ions (OH-) in solution, resulting in a pH of 7.1-14.0.
Common examples of acids include hydrochloric acid (HCl) and lactic acid, while bases include
sodium hydroxide (NaOH).
pH Scale and Its Importance
The pH scale ranges from 0 to 14, with lower values indicating acidity and higher values
indicating alkalinity.
A pH of 7 is considered neutral, which is the pH of pure water.
The pH of biological fluids is crucial for enzyme activity and metabolic processes.
Biomolecules and Their Functions
Comparison of Biomolecule Sizes
Nucleic acids are the largest biomolecules, followed by proteins, lipids, and carbohydrates (e.g.,
glucose).
This size hierarchy is important for understanding their roles in cellular functions and structures.
Energy Production from Biomolecules
Carbohydrates yield 36-38 ATP from glucose, while lipids yield approximately 144 ATP from
triglycerides (TAG).
Proteins yield about 36 ATP, but their primary role is not energy production.
Roles of Biomolecules in the Human Body
Carbohydrates provide immediate energy (ATP).
Lipids serve multiple functions: energy storage, temperature regulation, cell membrane
structure, hormone production, and protection.
, Proteins are involved in nearly all biological processes, including enzyme activity, immune
response (antibodies), and cellular signaling.
Protein Structure and Function
Structural Levels of Proteins
Primary structure: the sequence of amino acids in a polypeptide chain.
Secondary structure: local folding patterns such as alpha-helices and beta-sheets.
Tertiary structure: the overall 3D shape of a polypeptide, formed by interactions between R
groups.
Quaternary structure: the arrangement of multiple polypeptide chains into a functional protein.
Amino Acid Bonds and Polarity
Amino acids are linked by peptide bonds, which are covalent and polar.
The polarity of bonds affects solubility and transport across cell membranes.
Non-polar molecules can diffuse through membranes, while polar and ionic molecules require
transport proteins.
Human Physiology and Homeostasis
Transport Mechanisms
Active transport requires ATP and moves substances against their concentration gradient.
Passive transport occurs without energy expenditure, moving substances down their gradient.
Examples include diffusion, osmosis, and facilitated diffusion.
Fluid Tonicity and Cellular Response
Hypertonic solutions cause cells to shrink (crenate) due to water loss.
Hypotonic solutions lead to cell swelling and potential lysis due to water influx.
Isotonic solutions maintain cell size and shape, achieving equilibrium.
Menstrual Cycle Milestones
Day 1 marks the start of menstruation, while Day 14 indicates ovulation, characterized by a
spike in luteinizing hormone (LH) and estrogen.
The egg takes approximately 7-10 days to travel from the ovary to the uterus.
