Flashcards
Lipids
Flashcards do conjunto (14)
- 1What are the properties of lipids?Non-polar compounds (insoluble)
Made up of C, H and O (though less oxygen than carbohydrates) - 2What is the structure of fatty acids?Organic acids with a carboxyl (-COOH) group at one end and a long hydrocarbon tail (the R group) joined to the carboxyl group
General formula = RCOOH - 3What is the difference between saturated and unsaturated compounds?Saturated compounds only have C-C bonds
Unsaturated compounds have at least one C=C bond - 4What is the structure of triglyceride?3 ester bonds
Glycerol + 3 hydrocarbon tails
- 5How are triglycerides formed?Each ester bond is formed by a condensation reaction
The process in which triglycerides are synthesised is called esterification - 6How are triglycerides broken down?Each ester bond is broken in a hydrolysis reaction
- 7Complete the sentences: When _________, triglycerides release more energy for use in _____________ than carbohydrate. They also produce a lot of _____________ ________when oxidised (important for desert animals, e.g. camel's hump = fat). They are stored under the _____ where they act as a heat ____________.When OXIDISED, triglycerides release more energy for use in RESPIRATION than carbohydrate. They also produce a lot of METABOLIC WATER when oxidised (important for desert animals, e.g. camel's hump = fat). They are stored under the SKIN where they act as a heat INSULATOR.
- 8What is the structure of a phospholipid?Made up of one glycerol, one phosphate and two fatty acids
- 9Complete the sentence: The phosphate group is ___________ and the fatty acid tails are _____________.The phosphate group is HYDROPHILIC and the fatty acid tails are HYDROPHOBIC.
- 10Describe the two common arrangements of phospholipidsAs a micelle and as a monolayer
- 11What is the structure of cholesterol?Another type of lipid
Hydrocarbon ring structure attached to a hydrocarbon tail
The ring structure has a polar -OH group attached to it
- 12What are the functions of triglycerides?In animals and plants = energy storage molecules
Some bacteria use them to store both energy and carbon
Good for storage - long hydrocarbon tails of the fatty acids contain lots of chemical energy (lipids contain twice as much energy per gram as carbohydrates because of these tails)
Insoluble
Bundles together as insoluble droplets in cells as the fatty acid tails are hydrophobic (micelles) - 13What are the functions of phospholipids?Found in cell membranes of all eukaryotes and prokaryotes
Makes up the phospholipid bilayer
Cell membranes control what enters and leaves a cell
The center of the bilayer is hydrophobic so water-soluble substances cannot easily pass through it - 14What are the functions of cholesterol?In eukaryotic cells, cholesterol molecules help strengthen the cell membrane by interacting with the phospholipid bilayer
Has a small and flattened shape (allowing cholesterol to fit in between the phospholipid molecules in the membrane)
Bind to the hydrophobic tails of the phospholipids, causing them to pack more closely together (helps make membrane less fluid and more rigid)
Informações
- Descrição
- O usuário eliminou as informações de disciplina FlashCards sobre Lipids, criado por Usuário eliminado em 05-03-2018.
- Criado por
- Usuário eliminado · mar 2018
- Atualizado
- 5 mar 2018
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- Criado por Yinka F · 24 jan 2018
- Copiado por Yinka F · 5 mar 2018
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