Molecular and Cellular Biology Overview

Biomolecules

Building blocks of life in organisms.

Carbohydrates

Sugars and starches providing energy.

Glucose

Common carbohydrate vital for energy.

Proteins

Amino acid polymers with diverse functions.

Hemoglobin

Protein transporting oxygen in blood.

Lipids

Fats and oils for energy storage.

Phospholipid Bilayer

Structure forming cell membranes.

Nucleic Acids

DNA and RNA storing genetic information.

DNA

Genetic code determining organism traits.

Chemical Reactions

Breaking and forming chemical bonds in cells.

Covalent Bond

Electrons shared between atoms.

Ionic Bond

Transfer of electrons creating charged ions.

Water Properties

Unique characteristics crucial for life.

Cohesion

Attraction between water molecules.

Adhesion

Water's attraction to other surfaces.

High Heat Capacity

Water absorbs large heat amounts.

Solvent Properties

Water dissolves various substances effectively.

Density of Ice

Ice floats due to lower density.

Monosaccharides

Simple sugars, basic carbohydrate units.

Empirical Formula of Glucose

C₆H₁₂O₆ represents glucose composition.

Disaccharides

Two monosaccharides formed via dehydration synthesis.

Triglyceride

Lipid made of glycerol and fatty acids.

Fatty Acids

Long hydrocarbon chains with carboxyl group.

Amino Acids

Building blocks of proteins with unique side chains.

Amino Acid

Building blocks of proteins, containing amino and carboxyl groups.

Peptide Bond

Covalent bond linking amino acids in proteins.

Nucleic Acid

Biomolecules storing and transmitting genetic information.

Nucleotide

Monomer of nucleic acids, composed of phosphate, sugar, base.

Phosphate Group

Chemical group (PO₄) in nucleotides, vital for energy transfer.

Deoxyribose Sugar

Sugar component in DNA nucleotides.

Nitrogenous Base

Component of nucleotides; includes adenine, thymine, guanine, cytosine.

Genetic Code

Sequence of nitrogenous bases encoding instructions for organisms.

Abiogenesis

Theory proposing life arose from non-living matter chemically.

Miller-Urey Experiment

Demonstrated amino acids could form under early Earth conditions.

RNA World Hypothesis

Suggests RNA was first genetic material and catalyst.

Ribozymes

Self-replicating RNA molecules that catalyze reactions.

Hydrothermal Vent Hypothesis

Life may have originated at deep-sea hydrothermal vents.

Cell Membrane

Lipid bilayer controlling substance passage in cells.

Homeostasis

Maintenance of stable internal conditions in organisms.

Nucleus

Membrane-bound organelle containing DNA and regulating cell activities.

Gene Expression

Process of converting DNA information into functional products.

Transcription

Synthesis of RNA from a DNA template.

Ribosomal RNA (rRNA)

RNA component of ribosomes, essential for protein synthesis.

Carbohydrates

Biomolecules providing energy and structural support.

Lipids

Hydrophobic molecules, including fats and oils, for energy storage.

Proteins

Polymers of amino acids performing various biological functions.

Endoplasmic Reticulum (ER)

Network of membrane-bound tubes and sacs.

Rough ER

ER type involved in protein synthesis and modification.

Smooth ER

ER type involved in lipid synthesis and detoxification.

Ribosomes

Non-membrane-bound structures for protein synthesis.

mRNA

Messenger RNA translated into proteins by ribosomes.

Mitochondria

Double-membraned organelles producing ATP through respiration.

ATP

Adenosine triphosphate, energy currency of the cell.

Golgi Apparatus

Modifies, sorts, and packages proteins and lipids.

Lysosomes

Organelles containing enzymes for waste breakdown.

Vacuoles

Large sacs storing water and nutrients in plants.

Chloroplasts

Double-membraned organelles for photosynthesis in plants.

Chlorophyll

Pigment in chloroplasts capturing light energy.

Phospholipid Bilayer

Double layer forming semi-permeable cell membranes.

Selectively Permeable

Property allowing specific substances to pass membranes.

Fluid Mosaic Model

Describes dynamic nature of cell membranes.

Cholesterol

Stabilizes cell membranes by preventing tight packing.

Carbohydrates

Molecules aiding in cell recognition and adhesion.

Prokaryotic Cells

Cells lacking a true nucleus and organelles.

Eukaryotic Cells

Cells with a true nucleus and membrane-bound organelles.

Binary Fission

Asexual reproduction method in prokaryotic cells.

Nucleoid Region

Area in prokaryotes containing genetic material.

Cristae

Inner membrane folds of mitochondria increasing surface area.

Membrane-Bound Organelles

Organelles enclosed by membranes in eukaryotic cells.

Eukaryotic Cell Size

Generally larger and more complex than prokaryotic cells.

Reproduction Methods

Eukaryotic cells reproduce sexually or asexually.

Cell Wall

Rigid structure in plant cells made of cellulose.

Cytoplasmic Streaming

Movement of organelles within the cytoplasm.

Mitochondria

Organelles for energy production in eukaryotic cells.

Chloroplasts

Organelles for photosynthesis in plant cells.

Enzymes

Biological catalysts speeding up chemical reactions.

Enzyme Composition

Typically proteins, some are RNA molecules called ribozymes.

Catalysts

Substances that accelerate reactions without being consumed.

Enzyme Specificity

Enzymes catalyze specific substrates, resembling a lock-and-key.

Enzyme Reusability

Enzymes can be used repeatedly without permanent alteration.

pH Sensitivity

Enzymes have optimal pH ranges for efficient activity. Range:5-7

Temperature Sensitivity

Enzymes function best within specific temperature ranges.

Cofactors

Non-protein molecules assisting enzymes in catalysis.

Coenzymes

Organic molecules aiding enzymes, often derived from vitamins.

Enzyme-Substrate Complex

Temporary association between enzyme and substrate during reaction.

Active Site

Region on enzyme where substrate binds for reaction.

Catalysis Process

Enzyme stabilizes transition state, lowering activation energy.

Enzyme Recycling

Enzymes catalyze multiple reactions without being consumed.

Cofactor Carriers

Coenzymes transport functional groups between enzymes.

Coenzyme A (CoA)

Carries acetyl groups in metabolic pathways.

NAD+

Electron carrier in redox reactions.

FAD

Cofactor for enzymes in redox reactions.

Thiamine Pyrophosphate (TPP)

Activates pyruvate in citric acid cycle.

S-Adenosylmethionine (SAM)

Methyl group donor in methylation reactions.

Coenzyme Q (CoQ)

Participates in mitochondrial electron transport.

Tetrahydrofolate (THF)

Carrier of one-carbon units in metabolism.

Inorganic Cofactors

Metal ions aiding enzyme catalysis and stability.

Zinc (Zn)

Stabilizes enzyme structure and function.

Magnesium (Mg)

Cofactor in ATP-related enzymatic reactions.

Iron (Fe)

Involved in oxygen transport in hemoglobin.