Cell Structure
Nucleus
Contains genetic material (DNA).
Controls cell activities.
Lysosomes
Contain digestive enzymes to break down waste.
Phospholipid Bilayer
Composed of two layers of phospholipids.
Each phospholipid has a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) tails
Carbohydrates
Monomers: Monosaccharides (e.g., glucose, fructose).
Polymers: Polysaccharides (e.g., starch, glycogen, cellulose).
Functions: Energy storage, structural components.
Simple Diffusion
Movement of molecules from high to low concentration.
Mitochondria
Powerhouse of the cell.
Site of ATP (energy) production through cellular respiration.
Cytoskeleton
Provides structural support.
Composed of microtubules, microfilaments, and intermediate filaments.
Proteins
Integral proteins span the membrane.
Peripheral proteins are attached to the exterior or interior surfaces.
Lipids
Components: Glycerol and fatty acids.
Types: Fats, oils, phospholipids, steroids.
Functions: Long-term energy storage, insulation, make up cell membranes.
Facilitated Diffusion
Movement of molecules via transport proteins.
Ribosomes
Synthesize proteins.
Found free-floating or on rough endoplasmic reticulum.
Chloroplasts
Only found in plant cells
Site of photosynthesis.
Carbohydrates
Attached to proteins (glycoproteins) or lipids (glycolipids) on the extracellular side.
Proteins
Monomers: Amino acids.
Structure Levels: Primary, secondary, tertiary, quaternary.
Functions: Enzymes, transport, structural support, signaling.
Osmosis
Diffusion of water through a selectively permeable membrane.
Endoplasmic Reticulum (ER)
Rough ER: Studded with ribosomes; synthesizes proteins.
Smooth ER: Synthesizes lipids; detoxifies toxins.
Cell Wall
Only found in plant cells
Provides additional support and protection.
Cholesterol
Embedded within the bilayer in animal cells, adds fluidity and stability.
Nucleic Acids
Monomers: Nucleotides (composed of a sugar, phosphate group, and nitrogenous base).
Types: DNA and RNA.
Functions: Store and transmit genetic information.
Protein Pumps
Transport proteins that require energy (ATP) to move substances against the concentration gradient.
Golgi Apparatus
Modifies, sorts, and packages proteins and lipids for storage or transport.
Functions
Selective Permeability:
Regulates the entry and exit of substances.
Communication:
Receptor proteins receive signals from the environment.
Attachment:
Structural support by anchoring the cytoskeleton.
Definition
Macromolecules are large, complex molecules that are essential for various biological functions in living organisms. They are typically formed by the polymerization of smaller units called monomers.
Endocytosis
Process of taking materials into the cell by infolding of the cell membrane.
Phagocytosis: “Cell eating” (solid particles).
Pinocytosis: “Cell drinking” (liquids).