BCH 371 Exam 2-Questions With 100% Verified
Answers.
Biologically active lipids - ✔✔Are present in much smaller amounts than storage or
structural lipids and play vital roles as signaling molecules.
Arachidonic acid derivatives - ✔✔Enzymatic oxidation of these yields
prostaglandins, thromboxanes, and leukotrienes.
Prostaglandins - ✔✔Involved in inflammation and fever.
Thromboxanes - ✔✔Involved in formation of blood clots.
Leukotrienes - ✔✔Involved in smooth muscle contraction in lungs.
Polyketides - ✔✔Biologically active lipids with medicinal uses, synthesized similarly to
FA biosynthesis mostly by bacteria.
Biological Membranes - ✔✔Complex lipid-based structures forming flexible sheets
composed of lipids and proteins.
Cell Membrane - ✔✔Separates the cell from its surroundings.
Eukaryotic Cells - ✔✔Contain internal membranes dividing space into organelles.
,Membrane Functions - ✔✔Define boundaries, import/export nutrients and waste, retain
metabolites and ions within cell, sense external signals and transmit information into cell,
provide compartmentalization within cell, produce and transmit nerve signals, store
energy, support synthesis of ATP.
Without cell membrane - ✔✔Synthesis of ATP would not occur.
Compartmentalization - ✔✔Separates energy-producing from energy-consuming reactions
and keeps proteolytic enzymes away from important cellular proteins.
Membrane Bilayer - ✔✔Two leaflets of lipid monolayers in aqueous solution.
Hydrophilic Head Groups - ✔✔Interact with water on both bilayer sides.
Hydrophobic Tails - ✔✔Fatty acid tails packed inside the bilayer.
Membrane Thickness - ✔✔30-100 Å (3-10 nm).
Fluid Mosaic Model - ✔✔Membrane structure with fluid lipid and protein components.
Integral Proteins - ✔✔Firmly associated proteins spanning the lipid bilayer.
Peripheral Proteins - ✔✔Weakly associated proteins easily removed from membranes.
Lipid Composition - ✔✔Varies by organisms, tissues, and organelles.
Cholesterol - ✔✔Predominant in plasma membranes, absent in mitochondria.
, Galactolipids - ✔✔Abundant in plant chloroplasts, rare in animals.
Asymmetry of Bilayers - ✔✔Different lipid compositions in inner and outer leaflets.
Outer leaflet - ✔✔More positively charged.
Phosphatidylserine platelets - ✔✔Activates blood clotting.
Phosphatidylserine other cells - ✔✔Marks the cell for destruction.
Receptors - ✔✔Detect external signals like hormones and neurotransmitters.
Membrane Channels - ✔✔Facilitate transport of nutrients, ions, and neurotransmitters.
Membrane Enzymes - ✔✔Catalyze lipid biosynthesis and ATP synthesis.
Amphitropic Proteins - ✔✔Linked to membranes during regulatory events.
Peripheral (GPI-linked) membrane proteins - ✔✔Can be dissociated from the membrane
fairly easily during changes in ionic strength like pH changes.
Amphitropic and GPI linked proteins - ✔✔Are linked to the membrane during
specific regulatory events and can be reversibly removed.
Integral membrane proteins - ✔✔In the presence of strong detergents, they can be
removed from the membrane.
Fluid Structures - ✔✔Two-dimensional solution of oriented lipids.
Answers.
Biologically active lipids - ✔✔Are present in much smaller amounts than storage or
structural lipids and play vital roles as signaling molecules.
Arachidonic acid derivatives - ✔✔Enzymatic oxidation of these yields
prostaglandins, thromboxanes, and leukotrienes.
Prostaglandins - ✔✔Involved in inflammation and fever.
Thromboxanes - ✔✔Involved in formation of blood clots.
Leukotrienes - ✔✔Involved in smooth muscle contraction in lungs.
Polyketides - ✔✔Biologically active lipids with medicinal uses, synthesized similarly to
FA biosynthesis mostly by bacteria.
Biological Membranes - ✔✔Complex lipid-based structures forming flexible sheets
composed of lipids and proteins.
Cell Membrane - ✔✔Separates the cell from its surroundings.
Eukaryotic Cells - ✔✔Contain internal membranes dividing space into organelles.
,Membrane Functions - ✔✔Define boundaries, import/export nutrients and waste, retain
metabolites and ions within cell, sense external signals and transmit information into cell,
provide compartmentalization within cell, produce and transmit nerve signals, store
energy, support synthesis of ATP.
Without cell membrane - ✔✔Synthesis of ATP would not occur.
Compartmentalization - ✔✔Separates energy-producing from energy-consuming reactions
and keeps proteolytic enzymes away from important cellular proteins.
Membrane Bilayer - ✔✔Two leaflets of lipid monolayers in aqueous solution.
Hydrophilic Head Groups - ✔✔Interact with water on both bilayer sides.
Hydrophobic Tails - ✔✔Fatty acid tails packed inside the bilayer.
Membrane Thickness - ✔✔30-100 Å (3-10 nm).
Fluid Mosaic Model - ✔✔Membrane structure with fluid lipid and protein components.
Integral Proteins - ✔✔Firmly associated proteins spanning the lipid bilayer.
Peripheral Proteins - ✔✔Weakly associated proteins easily removed from membranes.
Lipid Composition - ✔✔Varies by organisms, tissues, and organelles.
Cholesterol - ✔✔Predominant in plasma membranes, absent in mitochondria.
, Galactolipids - ✔✔Abundant in plant chloroplasts, rare in animals.
Asymmetry of Bilayers - ✔✔Different lipid compositions in inner and outer leaflets.
Outer leaflet - ✔✔More positively charged.
Phosphatidylserine platelets - ✔✔Activates blood clotting.
Phosphatidylserine other cells - ✔✔Marks the cell for destruction.
Receptors - ✔✔Detect external signals like hormones and neurotransmitters.
Membrane Channels - ✔✔Facilitate transport of nutrients, ions, and neurotransmitters.
Membrane Enzymes - ✔✔Catalyze lipid biosynthesis and ATP synthesis.
Amphitropic Proteins - ✔✔Linked to membranes during regulatory events.
Peripheral (GPI-linked) membrane proteins - ✔✔Can be dissociated from the membrane
fairly easily during changes in ionic strength like pH changes.
Amphitropic and GPI linked proteins - ✔✔Are linked to the membrane during
specific regulatory events and can be reversibly removed.
Integral membrane proteins - ✔✔In the presence of strong detergents, they can be
removed from the membrane.
Fluid Structures - ✔✔Two-dimensional solution of oriented lipids.
