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What is a characteristic of the double bond in the lipid?
What is a characteristic of the double bond in the lipid?
Phosphatidyl inositol is a type of triglyceride.
Phosphatidyl inositol is a type of triglyceride.
False
All carbon-carbon bonds in fatty acids are single bonds.
All carbon-carbon bonds in fatty acids are single bonds.
False
Double bonds in fatty acids are always trans.
Double bonds in fatty acids are always trans.
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Monounsaturated fatty acids always have a double bond at the fifth carbon.
Monounsaturated fatty acids always have a double bond at the fifth carbon.
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Triacylglycerols are a component of cell membranes.
Triacylglycerols are a component of cell membranes.
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Lipases hydrolyze triglycerides into glycerol and one fatty acid.
Lipases hydrolyze triglycerides into glycerol and one fatty acid.
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Bile salts increase the surface tension of fat droplets.
Bile salts increase the surface tension of fat droplets.
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Lipase digestion of triglycerides occurs in the stomach.
Lipase digestion of triglycerides occurs in the stomach.
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Cholesterol is a type of sphingolipid.
Cholesterol is a type of sphingolipid.
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Gangliosides are the simplest form of sphingolipids.
Gangliosides are the simplest form of sphingolipids.
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Phospholipids are found only in the nervous system.
Phospholipids are found only in the nervous system.
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Lipid bilayers are crystalline in structure.
Lipid bilayers are crystalline in structure.
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Cholesterol increases fluidity in the crystalline state.
Cholesterol increases fluidity in the crystalline state.
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Lipid rafts are fluid and disordered.
Lipid rafts are fluid and disordered.
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Vitamin C is a fat-soluble vitamin.
Vitamin C is a fat-soluble vitamin.
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The hydroxyl group on the A-ring of a sterol is non-polar.
The hydroxyl group on the A-ring of a sterol is non-polar.
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Cerebrosides are found only in the nervous system.
Cerebrosides are found only in the nervous system.
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Lipid bilayer translocation requires protein for translocation.
Lipid bilayer translocation requires protein for translocation.
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The Na+/K+-ATPase directly transports Na+ and K+ ions during action potential in axons.
The Na+/K+-ATPase directly transports Na+ and K+ ions during action potential in axons.
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ABC transporters can transport material down their gradient.
ABC transporters can transport material down their gradient.
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Symporters can move two substances in opposite directions at the same time.
Symporters can move two substances in opposite directions at the same time.
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The β-subunit of Na+/K+-ATPase has binding sites for K+ ions.
The β-subunit of Na+/K+-ATPase has binding sites for K+ ions.
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Facilitated diffusion requires energy input.
Facilitated diffusion requires energy input.
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Uniporters move two substances in the same direction at the same time.
Uniporters move two substances in the same direction at the same time.
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The 'piggyback mechanism' is a type of active transport.
The 'piggyback mechanism' is a type of active transport.
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ABC transporters are involved in secondary active transport.
ABC transporters are involved in secondary active transport.
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Glucose can be transported out of the cell using the Na+/K+-ATPase.
Glucose can be transported out of the cell using the Na+/K+-ATPase.
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Acetylcholine is stored in the axon terminal.
Acetylcholine is stored in the axon terminal.
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Amylopectin is a polymer present in glycogen
Amylopectin is a polymer present in glycogen
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Glycoproteins and glycolipids are common fuel-storage molecules
Glycoproteins and glycolipids are common fuel-storage molecules
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Cellulose is a glucose polymer formed between #2 and #3C atoms
Cellulose is a glucose polymer formed between #2 and #3C atoms
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Glycogen has a highly branched form that allows it to be rapidly assembled or disassembled
Glycogen has a highly branched form that allows it to be rapidly assembled or disassembled
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Amylopectin has a linear chain structure
Amylopectin has a linear chain structure
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Glycogen is typically stored in compact granules
Glycogen is typically stored in compact granules
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Cellulose has beta (1→3) glycosidic bonds
Cellulose has beta (1→3) glycosidic bonds
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Glycoproteins and glycolipids have a limited repertoire of complex molecules
Glycoproteins and glycolipids have a limited repertoire of complex molecules
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Chitin is a type of polysaccharide found in the cell walls of insects and crustaceans.
Chitin is a type of polysaccharide found in the cell walls of insects and crustaceans.
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N-acetylglucosamine is a type of sugar found in DNA.
N-acetylglucosamine is a type of sugar found in DNA.
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Animals can digest chitin.
Animals can digest chitin.
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Glycosylation occurs in the Golgi apparatus.
Glycosylation occurs in the Golgi apparatus.
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O-glycosylation occurs in the endoplasmic reticulum.
O-glycosylation occurs in the endoplasmic reticulum.
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Biofilms are composed of proteins and lipids.
Biofilms are composed of proteins and lipids.
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Glycoproteins are built one residue at a time in the ribosome.
Glycoproteins are built one residue at a time in the ribosome.
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Disaccharides are the main components of biofilms.
Disaccharides are the main components of biofilms.
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Study Notes
Here are the study notes for the provided text:
Lipids
- Lipids are a type of biological molecule, including fats, waxes, and related compounds.
- Examples of lipids include syhenul, plau, and waxtslid.
Structure and Composition
- Lipids are composed of fatty acid chains, which are long chains of carbon atoms with hydrogens attached.
- The fatty acid chains can be single or double, with the double bonds forming a "kink" in the chain.
- Lipids can also have a glycerol backbone, which is a three-carbon molecule that serves as the central structure of the lipid.
Types of Lipids
- Waxes are a type of lipid that consist of a long-chain fatty acid and a long-chain alcohol.
- Fats are a type of lipid that consist of a glycerol backbone and three fatty acid chains.
- Plau lipids are a type of lipid that is found in plant cells.
Functions of Lipids
- Lipids serve as a source of energy for cells.
- They are also important for maintaining the structure and function of cell membranes.
- Lipids can act as hormones or signaling molecules, helping to regulate various cellular processes.
Other Important Concepts
- Lipids are non-polar molecules, which means they are insoluble in water.
- They are often stored in cells as droplets or as part of the cell membrane.
- Lipids can be broken down into smaller molecules, such as fatty acids and glycerol, through a process called lipolysis.
Phospholipids
- Phosphatidyl inositol is a phospholipid present on the interface of the membrane, concentrated in lipid rafts.
- Phospholipids are the major constituents of membranes and are responsible for the membrane being a bilayer.
- Phospholipids have a complex structure consisting of a molecule of glycerol, attached to two fatty acids, a phosphate, and usually one other small molecule (X).
Fatty Acids
- Most carbon-carbon bonds in fatty acids are single, but they may contain one, two, or more carbon-carbon double bonds.
- Double bonds in fatty acids are most often cis.
- For monounsaturated fatty acids, the double bond is usually between carbon atoms 9 and 10.
Triglycerides
- Triglycerides are not part of the cell membrane and aggregate into globules, stored as an energy source.
- Triglycerides are a component of oils and can be hydrolyzed to produce glycerol and three fatty acids.
Lipases
- Lipases hydrolyze triglycerides (fats) into their component fatty acid and glycerol molecules.
- Initial lipase digestion occurs in the lumen of the small intestine, where bile salts reduce the surface tension of the fat droplets, allowing lipases to attack the triglyceride molecules.
Glycerophospholipids
- Glycerophospholipids are the major constituents of membranes and are responsible for the membrane being a bilayer.
- Glycerophospholipids have a complex structure consisting of a molecule of glycerol, attached to two fatty acids, a phosphate, and usually one other small molecule (X).
Phospholipase Action
- Phospholipases are enzymes that cleave ester bonds within phospholipids.
- Phospholipases contribute to the stability and insulation of nerve cells.
Sphingolipids
- Sphingolipids are a type of lipid that contains a sphingoid base, a fatty acid, and a single sugar residue.
- Cerebrosides are a type of sphingolipid that contains a sphingoid base, a fatty acid, and a single sugar residue, commonly found in the nervous system.
- Gangliosides are the most complex sphingolipids, containing multiple sugar residues in addition to a sphingoid base and a fatty acid, predominantly present in the nervous system.
Sterols
- Sterols are a subgroup of steroids with a hydroxyl group at the 3-position of the A-ring.
- Sterols are amphipathic lipids synthesized from acetyl-coenzyme A via the HMG-CoA reductase pathway.
- The overall molecule is quite flat, with a hydroxyl group on the A-ring that is polar, while the rest of the aliphatic chain is non-polar.
Ceramides
- Ceramides are the simplest form of sphingolipids, composed of a sphingoid base and a single fatty acid linked by an amide bond.
- Ceramides serve as precursors for more complex sphingolipids and are involved in cellular signaling pathways related to apoptosis and stress responses.
Sphingomyelins
- Sphingomyelins consist of a sphingoid base, a fatty acid, and a phosphorylcholine or phosphorylethanolamine head group.
- Sphingomyelins are abundant in cell membranes, especially in myelin sheaths.
Waxes
- Waxes are esters made of long-chain alcohols and fatty acids.
- Waxes provide protection, especially to plants, in which wax covers the leaves of plants.
Fat-Soluble Vitamins
- Fat-soluble vitamins include vitamins A, D, E, and K.
- Fat-soluble vitamins play integral roles in a multitude of physiological processes, such as vision, bone health, immune function, and coagulation.
Lipid Bilayer and Membrane Fluidity
- The lipid bilayer is a 2D array of amphipathic molecules that forms spontaneously and is very fluid.
- The lipid bilayer is formed from glycerophospholipids and sphingolipids.
- Cholesterol is present in the lipid bilayer, which restricts lipid movement and serves as a fluidity buffer.
Lipid Bilayer Translocation
- Lipids move laterally easily while lipid movement between layers is less frequent.
- Lipid movement between layers may require protein for translocation.
- Interleaflet movement is essential for asymmetry.
Lipid Bilayer Asymmetry
- The two leaflets in the bilayer are not identical.
- Some lipids have to do with the orientation of lipid-synthesizing enzymes.
- Some lipids have to do with translocases or "flippases".
- The function of the membrane is more than just as a "cell sack".
Factors Affecting Melting Temperature
- The degree of saturation affects the melting temperature.
- The chain length affects the melting temperature.
Cellular Membranes
- Glucose transport works by a rocker mechanism.
- Glucose binds on one side, eliciting a conformational change, which exposes the molecule to the other side.
- Glucose transport moves in either direction and is an example of facilitated (passive) transport.
Primary and Secondary Active Transport
- Active transport requires energy input and moves against the gradient.
- The Na, K-ATPase reaction cycle hydrolyzes 1 ATP to pump 3Na+ ions out of the cell and 2 K+ ions inside the cell.
Secondary Active Transporter
- The piggyback mechanism uses an established gradient to transport material.
- Symporters can move glucose into the cell with Na+.
- The Na+ gradient is already established by the Na+/K+ ATPase.
ABC (ATP-Binding Cassette) Transporters
- ABC transporters are composed of two membrane-integral domains and two ATP-hydrolyzing domains.
- ABC transporters use ATP to transport material into the cell.
- ABC transporters transport material against its gradient.
Acetylcholine Release
- Acetylcholine (ACh) is a neurotransmitter stored in synaptic vesicles.
- When a nerve impulse reaches the axon terminal, Ca2+ ions from the ECF enter the cell, and ACh is released.
Polysaccharides
- Polysaccharides are common fuel-storage molecules.
- Polysaccharides can be joined in a variety of ways.
- Tremendous repertoire of complex molecules.
Glycoproteins and Glycolipids
- Glycoproteins and glycolipids are polysaccharides attached to proteins or lipids.
- Amylopectin is a polymer present in starch.
- Glycogen is a polymer that resembles amylopectin, but with branches every 12 residues.
Structural Carbohydrates
- Cellulose is a glucose polymer formed between #1 and #4C atoms.
- Cellulose is a rigid and strong structure that provides rigidity and strength for plant cell walls.
Disaccharides
- Disaccharides occur in nature most commonly as breakdown products of polysaccharides.
- Animals do not make cellulose and most cannot digest it.
- Microbes do, and normal microflora for ruminants.
O-Glycosylation
- O-glycosylation is a highly specific process that gives tremendous variety and specificity to molecules.
- O-glycosylation tends to be built one residue at a time in the Golgi apparatus.
Purpose of Glycosylation
- The purpose of glycosylation is to:
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- Provide a specific signal for protein targeting
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- Regulate protein function
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- Modify the immune response
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- Modulate cell-cell interactions
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- Influence the degradation of proteins
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Description
This quiz covers the basics of lipid chemistry and biology, including their structure, functions, and importance in the human body.
