Glycerol backbone (except for steroids), fatty acids (and/or P, variable group) joined by ester bonds
Example of a saturated FA
Example of an unsaturated FA
Describe structure of a phospholipid
Glycerol backbone + 2 FA's + P & a variable group (Amphipathic)
Give 2 examples of phospholipids
What is a trans fat and why are they bad for you?
Unsaturated FA that has a trans isomer across a double bond. Rare in nature, straight, hard to digest. Raise LDL and decrease HDL cholesterol. 100,000 deaths/year
Insoluble in water, 4 ring structure + tail, e.g. cholesterol
List 6 main functions of lipids
Stored energy (triglycerides) Cell structure (phospholipids, cholesterol) Protection (feet) Chemical regulators (steroid hormones such as estrogen, Vitamins A,D,K) Digestion (bile acids help digest fats) Insulation
What does vitamin A do?
Enhances vision retinal + opsin→ rhodopsin
What does vitamin D do?
Promotes absorption of Ca and Phosphate
What does vitamin K do?
Blood clotting (promotes synthesis of promthrombin) Formed by E. Coli in LI
What is rickets? Symptoms? Treatments?
Vitamin D deficiency. Patient will have soft, pliable bones. Add vitamin D supplement.
What is osteomalacia?
Vitamin D deficiency in adults
Why is lung surfactant important?
Reduces surface tension in alveoli to allow easy expansion. W/out it alveoli collapse and hyaline membrane fill spaces.
What is the disease that results from not enough surfactant and what % of babies have it?
Describe amyloid precursor protein pathway to Alzheimers
APP is cleaved by a beta secretase (instead of alpha)→the β-amyloid leaves the cell and forms amyloid plaques that interfere with membrane function
Describe the tau protein pathway to Alzheimers
tau protein in the cell becomes hyperphosphorylated→Aggregates & forms neurofibrillary tangles→axons degenerates cuz organelles are impaired
Detail a role of proteins in Parkinson's disease
Mutation in gene for protein alpha synuclein results in an altered synuclein that misfolds and forms cytoplasmic granules called lewy bodies. Form clumps cuz they cant find their proper place in mitochondrial membrane.
Describe cystic fibrosis
Mutation in gene that codes for CFTR results in inability to pump Cl- out of epithelial cell. Water is drawn into the cell, drying out the airway mucus.
Discuss hereditary spherocytosis.
Autosomal dominant, chr. 8 mutation results in either an abnormal ankryin (more common) or spectrin protein. Results in balloon shaped RBC's, mild anemia, enlargement of spleen. Most common RBC disorder.
Explain polycystic kidney disease
Defect in PKD gene #1 or #2 results in defective polycystin channels that dont allow Ca to leave the cell. Ca salts develop→water accumulates into cyst like growths along nephrons
Describe basic chemical unit and bonding of a nucleic acid
Made of nucleotides joined by phosphodiester bonds. Nucleotides made of a 5 Carbon sugar, Phosphate group, and a nitrogenous base.
Describe the physical structure of DNA and forces that stabilize it
2 polynucleotide chains complexed in an antiparallel manner around a central axis forming a double helix. Stabilized by H bonds e/ bases and base stacking and ionic conditions.
Identify 3 forms of DNA
B: most common, right-handed, high affinity w/ trans. factors A: right-handed, low humidity. Z: left-handed, inactive & regulatory