カテゴリー 全て - chemical - proteins - molecules - biological

によって Danica F Barnett 12時間前.

17

Chemical Bonds

Various types of chemical bonds and interactions play crucial roles in the structure and function of biological molecules. Ionic bonds involve the attraction between charged ions, such as in common salt (

Chemical Bonds

Chemical Bonds

Cell Components

Eukaryotic Cells (Plants, Animals, Fungi, Protists)
Nucleus, ER, Golgi, mitochondria, lysosomes, and vaculoes

Vacuoles

Animals: Small vesicles for storage & transport

Plants: Large central vacuole (Stores water, ions, nutrients, maintains pressure)

Lysosomes (Animal Cells)

Break down waste, foreign particles, old organelles

Contain Hydrolytic Enzymes

Mitochondria

ATP production via Cellular Respiration

Own DNA & Ribosomes (Endosymbiotic Theory)

Double membrane (Inner membrane forms cristae)

Golgi Apparatus

Produces lysosomes

Modifies, sorts, packages proteins & lipids

Endoplasmic Reticulum (ER)

Smooth ER (Lipid synthesis, Detoxification, Calcium storage)

Rough ER (Ribosomes attached, Protein synthesis & transport)

Nucleus

Nucleolus (rRNA Synthesis) – Ribosome assembly

Chromatin – Genetic storage

Nuclear Envelope – Regulates transport

Cell Membrane, Cytoplasm, and cytoskeleton

Cytoplasm & Cytoskeleton

Cytoskeleton (Protein Filaments)

Intermediate Filaments – Structural support

Microfilaments (Actin) – Shape, movement

Microtubules (Tubulin) – Transport, spindle fibers

Cytosol (Water, enzymes, dissolved molecules)

Cell Membrane

Cholesterol (in animals)

Carbohydrates (Glycoproteins, Glycolipids) – Cell recognition

Proteins – Transport, signaling

Phospholipid Bilayer (Hydrophobic tails, Hydrophilic heads)

Larger & more complex
Membrane-bound organelles
Prokaryotic Cells (Bacteria & Archaea)
Flagella (Protein-based movement structure)
Nucleoid (Circular DNA, No nucleus)
Plasma Membrane (Phospholipid bilayer)
Ribosomes (Protein + rRNA)
Cell Wall (Peptidoglycan in bacteria)
No membrane-bound organelles

Biological Molecules

Nucleic Acids
Polymer: DNA & RNA
Monomer: Nucleotides (A, T, G, C, U)

Functions: Store genetic information, Direct protein synthesis

Proteins
Polymer: Polypeptides
Monomer: Amino Acids

Structure: Primary, Secondary (α-helix, β-sheet), Tertiary, Quaternary

Functions: Enzymes (catalysts), Transport proteins, Receptors, Structural components (cytoskeleton, extracellular matrix)

Lipids
Phospholipids, Triglycerides, Steroids

Found in: Cell membranes (phospholipid bilayer), Hormones (steroids), Energy stores (fat droplets)

Carbohydrates
Polymer: Polysaccharides (Starch, Glycogen, Cellulose)

Found in: Cell walls (cellulose, peptidoglycan), cell membranes (glycoproteins, glycolipids)

Monomer: Monosaccharides (Glucose, Fructose)

Dipole-Dipole

Ion-Dipole
attractive force between an ion and a neutral molecule
interaction between polar molecules

Hydrophobic interactions

interaction of nonpolar substances in the presence of polar substances

Hydrophilic interactions

interaction of polar substances in the presence of nonpolar substances
Water

has high specific heat

w' Hydrogen bonds, helps regulate temperature

adhesion: interaction with molecules of different substance

ex: allows water to travel up the trees

cohesion: interaction with molecules of the same substance.

Van der Waals interaction

weak interactions between atoms; interaction of electrons of nonpolar substances

Hydrogen bonds

present in DNA and proteins
Hydrogen bonded to a highly electronegative atom
electronegativity: Measure of the ability of an atom to attract electrons in the context of a chemical bond
Hydrogen bonding occurs w/ FON (Florine, Oxygen, Nitrogen)
polar

ionic bonds

attraction between charged ions
ex: NaCl Na has a charge of +1 and Cl has a charge of -1

covalent bonds

polar covalent bond
electrons are shared unequally due to difference in electronegativity (EN)

ex: H2O Oxygen has a higher EN, so Hydrogen's electrons are pulled toward Oxygen

shared electron pairs
ex: H2O Oxygen shares its electrons w/ two Hydrogen atoms, making a stable electron configuration