Introduction to Biochemistry Principles

• Biochemistry applies chemistry to study biological processes at the cellular and molecular levels.
• It emerged as a distinct discipline around the 20th century.
• Scientists combined chemistry, physiology, and biology to investigate the chemistry of living systems.
• This involves studying the structure and behavior of complex molecules in biological material.
• It studies how these molecules form cells, tissues, and organisms.

Principles of Biochemistry

• Cells are the fundamental structural units of life.
• Cells require a constant energy source to maintain an organized state.
• Living processes involve thousands of chemical reactions.
• Precise regulation and integration of chemical reactions are vital for life.
• Glycolysis is an important reaction found in almost all organisms.
• All organisms use the same types of molecules, like carbohydrates, proteins, lipids, and nucleic acids (CHO).
• DNA encodes instructions for growth, reproduction, and development.

Cells

• Cells are the smallest living unit
• They grow, reproduce, use energy, adapt, and respond to their environment.
• Cells may be an entire organism or part organisms.
• Cells may be prokaryotic or eukaryotic.
• Prokaryotes are bacteria and lack a nucleus or organelles.
• Eukaryotes comprise most other cells containing a nucleus and membrane-bound organelles, such as plants, fungi, and animals.

Prokaryote Cells

• Prokaryotes are the simplest and earliest evolved cell type.
• They're unicellular and do not differentiate into multicellular forms.
• These cells may be adjacent after division, but lack communication between them.
• Prokaryotes lack intracellular organelles.
• They consist of 3 architectural regions: appendages of Flagella and villi and a cell envelope or cell wall that consists of a capsule and a cytoplasmic region.

Eukaryote Cells

• Eukaryotes have a nucleus and membrane-bound organelles.
• They include fungi, animal cells, and plant cells.
• Eukaryotes are 10x larger than prokaryotic cells and up to 1000 times greater in volume.
• There are two main types of eukaryotic cells: animal and plant.

Organelles

• Mitochondria have a double membrane with cristae that function in energy production through metabolism.
• Mitochondria contain their own DNA and are suspected to have originated as captured bacteria.
• Plasma Membrane is a lipid, protein, and carbohydrate complex that provides a barrier containing transport and signaling systems.
• Nucleus includes a double membrane surrounding the chromosomes and nucleolus.
• Pores allow communication with the cytoplasm.
• The nucleolus is a site for ribosome RNA synthesis.
• Chloroplasts (plastids) are surrounded by a double membrane containing thylakoid membranes, and they contain DNA.
• Chloroplasts are responsible for photosynthesis and trapping energy for sugar synthesis and were captured bacteria.
• Rough Endoplasmic Reticulum (RER) is a network of interconnected channel-forming membranes covered with ribosomes.
• Ribosomes are located on the RER and synthesize proteins for secretion or membrane localization.
• Ribosomes are protein and RNA complexes responsible for protein synthesis.
• Smooth Endoplasmic Reticulum (SER) has interconnected channel-forming membranes that synthesizes and metabolizes lipids.
• The SER contains enzymes for detoxification.
• Golgi apparatus comprises a series of stacked membranes.
• Vesicles transport materials from the RER, processing proteins to a mature form.
• Vesicles then carry membrane proteins to their final destination.
• Lysosomes are membrane-bound organelles that degrade proteins and ingest materials.
• Vacuoles contain water and storage materials in plants.
• Peroxisomes or Microbodies produce and degrade hydrogen peroxide.
• A rigid cell wall is present in plant cells, in addition to their cell membranes.
• Cytoplasm includes the liquid cytosol that encloses membranous organelles.
• Cytoskeleton contains protein filaments in the cytosol that provide cell shape and movement.

Biomolecules

• Molecules are the building blocks of cells.
• Animal and plant cells contain approximately 10,000 biomolecules.
• Water is 50-95% of cell content by weight.
• Ions like Na+, K+, and Ca+ account for 1%.
• Organic biomolecules include C, H, N, O, P, and S.
• Infinite types of molecules contain carbon (C).
• Biomolecules are derived from hydrocarbons and their chemical properties are determined by functional groups.
• Types of biomolecules include carbohydrates, amino acids, proteins, nucleotides, nucleic acids, and lipids.

Carbohydrates

• They are very abundant organic molecules.
• Plants initially synthesize carbohydrates from reactions involving photosynthesis.
• Monosaccharides: basic unit of carbohydrates.
• Monosaccharides form larger molecules, such as glycogen, starch, or cellulose.
• Carbohydrates store energy as starch in plants or as glycogen in animals.
• They provide energy through metabolic pathways and cycles.
• They supply carbon for synthesizing compounds.
• Carbohydrates can be structural components in cells and participate in intercellular communications.

Amino Acids and Proteins

• The building blocks of proteins are amino acids.
• There are 20 commonly occurring amino acids.
• Amino acids contain amino and carboxyl group function groups for behavioral properties.
• R groups (side chains) dictate an amino acids chemical properties, determining protein folding and biological functions.
• Individual amino acids are connected by peptide bonds.
• Proteins function as transport or structural proteins, enzymes, antibodies, or cell receptors.

Nucleotides and Nucleic Acids

• Nucleotides are the basic building blocks of nucleic acids (RNA and DNA).
• A nucleotide consists of a sugar molecule ribose or deoxyribose attached to a phosphate group and nitrogen-containing base.
• The flow of genetic information is the overall function of Nucleotides and Nucleic acids .

Fatty Acids

• Fatty acids are monocarboxylic acids that contain an even number of C atoms.
• There are saturated (C-C sb) and unsaturated (C-C db) types of fatty acids.
• Fatty acids are components of lipid molecules such as triacylglycerol, steroids, and fat-soluble vitamins.
• Their functions include energy storage, membrane structure, insulation, and hormone synthesis.

Biochemical Reactions

• Metabolism sums up the chemical reactions in a living organism, which is coordinated and purposeful.
• Anabolism is the process of energy-requiring biosynthetic pathways.
• Catabolism is the degradation of fuel molecules and the production of energy for cell function.
• All such reactions are catalyzed by enzymes.
• Metabolism functions for acquisition and utilization of energy, synthesis of molecules for cell structure, proteins, nucleic acids, lipids, and elimination of waste material.

Energy for Cells

• Living cells are inherently unstable.
• A Constant flow of energy prevents them from becoming disorganized.
• Cells obtain energy mainly by the oxidation of biomolecules (e- transferred from 1 molecule to another).
• This energy captured by cells is used to maintain cellular structure and functions.
• Complex cell structures maintain high internal order through synthesis of biomolecules.
• Transport Across Membranes regulates the passage of ions and molecules from one area to another.
• Cell Movement refers to the coordinated activities needed to sustain life that require cell components.
• Waste Removal helps prevent toxicity since animal cells convert food into toxic compounds.

Water

• Most abundant substance in living systems.
• Water is approximately 70% or more of the weight of most organisms.
• Almost 75% of the planet is covered in water, which is 97% seawater and 3% freshwater.
• Freshwater comprises 68% ice caps, 30% ground water ,and 2% surface water.
• Surface water consists of 87% lakes, 11% swamps, and 2% rivers.
• Pure water boils at 100°C and freezes at 0°C.
• A water (H₂O) molecule comprises of one oxygen and two hydrogen atoms
• Each water molecule acts polar, in that the oxygen atom attracts more than its "fair share" of electrons.
• This means the oxygen end is negative and the hydrogen is positive.
• Hydrogen bonds are formed when a negative oxygen end attracts to the positive hydrogen end of another.

Properties of Water

• Water has cohesion.
• It has adhesion.
• Water acts as a solvent.
• Water has thermal properties.

Cohesion

• Occurs because of polarity within the water molecule, as well as its capability to form hydrogen bonds.
• Results in surface tension and produces a surface film on the water.

Adhesion

• The attraction between water and other substances.
• Water makes hydrogen bonds with other surfaces.
• Capillary action occurs when water bonds to a surface because of a combination of adhesive forces.
• Hydrophilic substances are chemically attracted to water.
• Hydrophilic components can dissolve in water and also contain molecules such as glucose.
• Water adheres to hydrophilic substances.
• Hydrophobic substances that water fearing and not chemically attracted to water.
• All hydrophobic lipids are non polar including fats and oils.
• Hydrophobic molecules dissolve in other solvents.

Water in the Body

• Blood plasma is primarily water (95%) and dissolved substances to provide transport in the body..
• Soluble glucose moves with the blood plasma because it is a polar molecule.
• Soluble amino acids move with the blood plasma because they have negative charges and positive.
• Water carries the majority of oxygen that is hemoglobic.

Thermal

• Water has a high specific heat capacity.
• It requires 4.2 Joules to raise the temperature of 1 gram by 1 degree Celcius.
• Water has both a high heat of vaporization is also needed to change change from a liquid to gas or vapour.
• Water serves as a coolant because It takes a great amount of energy for it to shift temperature.

Explore the core principles of biochemistry, which applies chemistry to biological processes at the cellular and molecular levels. Learn about the fundamental structural units of life, energy requirements, chemical reactions, regulation, and the role of DNA. Discover the universal use of molecules like carbohydrates, proteins, lipids, and nucleic acids in living organisms.