Building a cell (p2) Flashcards
(32 cards)
Macromolecules
- Polymers composed of monomers that are linked together by covalent bonds
To exchange atoms and form macromolecules:
- Molecules must be moving/collide which can’t happen at absolute 0
Dehydration Synthesis
- Water is a product
- Monomer -> Dimer
- Forms COVALENT bonds, releases water
- Slow reactions
Hydrolysis
- Water is a reactant
- Breaks down Dimers and Polymers
- Breaks bonds, water is formed and energy often released
How to speed up the process of making/breaking down Macromolecules
- increase concentration of monomer to cause collision
- increase temp to increase motion & collisions
- IN CELLS: Enzymes - bc they control concentration of monomers and the temp
Carbs (CH2O)n
- COVALENTLY bonded
Monosaccharides
Simplest form of carb
- Glyceraldehyde (triose) - base of many reactions that lead to ATP
- Ribose (pentose)
- Glucose (hexose)
Disaccharides
Sucrose (glucose + fructose)
- Held together by GLYCOSIDIC bonds (need special enzyme to break and form this bond)
Polysaccharides
- Dense structures (Ex. Glycogen)
- Enzymes form them out of sugar subunits
- Store monosaccharides for energy
- Structure is BRANCHED (Glycogen, Amylopectin) or UNBRANCHED (Starch)
- Form rigid biological structures like cellulose and chitin
Cellulose
- Formed by H-bonds
-> So it can be easily broken down with the right enzyme that digests cellulose and break H-bond systems
Lipids
- Fats (used for metabolism)
- Steroids (form vitamins/hormones)
- Phospholipids (form cell membranes)
Fats
- Used for Metabolism
- Glycerol + fatty acid
- No charge
- More bonds = more stored energy
Types of Fats
- Saturated fatty acid
-> No double bonds, solid at room temp - Unsaturated trans
-> H-atoms opposite side, semi-solid at room temp
-> Bonds aren’t saturated with Hydrogen
-> Collect in bloodstream as clumps - Unsaturated cis
-> H-atoms on same side, liquid at room temp
-> Bent configuration = more flexible, better for health
-> MONO = one double bond
-> POLY = multiple double bonds, more bent
Phospholipids
- Amphipathic molecules (Hydrophobic head, Hydrophilic tail)
-> form cell membranes & keep water out of membrane - Composed of saturated/unsaturated fats
- Phospholipids had to evolve first before cells
Steroids
Cholesterol is a precursor for the synthesis of hormones and vitamin
Amino acids & Polypeptides
- Amino acids form polypeptides.
- Amino acids are linked with PEPTIDE BONDS (Covalent)
-> Dehydration synthesis forms PEPTIDE BONDS - Amino acids - monomer/subunit
- Amino acids have: Amino group (NH4) + Carboxyl group (COOH)
Nonpolar Amino acids
- Hydrocarbon side chain
-> Other than Glycine: has Hydrogen side chain
Polar Amino acids
- Net (+/-) or partial (uncharged) sidecahins
Electrically charged Amino acids
- Either very attractive or very repulsive, impacting whether amino acids accepts or released H+
-> Accepts H+, env. = more acidic = neg charge
-> Releases H+, env. = more basic = pos charge
Primary structure
Polypeptide is a polymer of amino acids (sequence of amino acids)
Secondary structure
- Helix or Pleated sheet
-> Formed by H-bonding along amino acid chain - How it folds
Tertiary structure
- 3D folding of polypeptide chain bc of interactions from distant amino acids
- Ex. Globin
Quaternary structure
- Multiple proteins (folded polypeptide chains) form one protein
- Ex. Hemoglobin (in RBC, transport Oxygen)
Minimal Energy State
When entire protein is fully stable and has fully folded
A change in one amino acid changes protein structure
- Missense mutation in Hemoglobin causes SICKLE CELL ANEMIA
- 1 normal Hemoglobin gene + mutation = protection from Malaria
- 2 normal Hemoglobin genes + mutation = SICKLE CELL ANEMIA