B1.1 Carbohydrates and lipids Flashcards
The simplest form of carbohydrates, consisting of single sugar units
like glucose and fructose
Monosaccharides
These are the basic building blocks for more complex carbohydrates
What is the primary function of lipids in the human body?
Long-term energy storage and insulation in the human body.
They are also key components of cell membranes
True or False: Saturated fats are typically liquid at room temperature.
False
Saturated fats are usually solid at room temperature due to their straight molecular structure, which allows them to pack tightly.
The process of forming a triglyceride
Triglyceride forms by a condensation reaction between one glycerol molecule and three fatty acid molecules.
This process results in the release of water molecules
Type of bond formed between amino acids in a protein
Peptide bond
This bond is crucial for the protein’s structure and function
What is the role of phospholipids in cells?
Phospholipids form the primary structure of cell membranes
Their hydrophilic and hydrophobic ends make them ideal for creating the cell membrane’s bilayer
The basic structure of a carbohydrate molecule
Carbon, hydrogen, and oxygen atoms, typically in a 1:2:1 ratio.
This basic formula is Cn(H2O)n
True or False: Lipids are polar molecules
False
Lipids are non-polar, making them hydrophobic (water-repelling)
What distinguishes a saturated fatty acid from an unsaturated one?
Saturated fatty acids have no double bonds in their hydrocarbon chain, whereas unsaturated fatty acids do
This affects their physical state at room temperature - saturated fats are usually solid, and unsaturated fats are typically liquid
How do carbohydrates serve in cellular respiration?
Carbohydrates are broken down to glucose, which is used in cellular respiration to produce ATP, the cell’s energy currency
This process is vital for providing energy to cells
It is a polysaccharide that serves as a form of energy storage in animals
Glycogen
Where is glycogen stored in the body?
In the liver and muscles
Describe the ‘hydrophobic effect’ in relation to lipids.
The tendency of non-polar lipid molecules to aggregate in water to minimize their exposure to water molecules.
This effect is critical in forming cell membranes and lipid bilayers.
Long chains of monosaccharides linked by glycosidic bonds. Example: Starch
Polysaccharides
They serve various functions, including energy storage and structural support.
Fill in the blank: _______ are the simplest lipids, formed from glycerol and fatty acids.
Triglycerides
They are the main form of stored energy in animals
What is the significance of cholesterol in the body?
Cholesterol is essential for the synthesis of cell membranes, hormones, and vitamin D
It’s transported in the blood by lipoproteins
The structure of a phospholipid molecule
It has a hydrophilic head containing a phosphate group and two hydrophobic fatty acid tails
This dual nature is crucial for forming cell membranes
True or False: Glycogen is a type of lipid
False
Glycogen is a polysaccharide, a complex carbohydrate
What is the difference between alpha and beta glucose?
The difference lies in the position of the -OH group on the first carbon: alpha glucose has it below the ring plane, beta glucose above.
This affects how they form polysaccharides like starch and cellulose
How do unsaturated fats affect cholesterol levels?
Unsaturated fats can help lower LDL (bad) cholesterol levels while maintaining or increasing HDL (good) cholesterol levels.
This makes them a healthier choice compared to saturated fats
What is the primary function of carbohydrates in living organisms?
Source of energy and as structural components in cells
They are key in energy metabolism and cell structure
Describe the significance of the lipid bilayer in cell membranes
The lipid bilayer forms a barrier that controls the entry and exit of substances in and out of the cell
Its fluid nature allows for cell flexibility and transport
Fill in the blank: Cellulose is a _________ made of beta-glucose units
Polysaccharide
It’s a major component of plant cell walls, providing structural support
How do trans fats affect human health?
They increase the risk of heart disease by raising LDL (bad) cholesterol and lowering HDL (good) cholesterol
They are commonly found in processed foods
Identify the bond type that connects monosaccharides in disaccharides
Glycosidic bond
This bond forms through a dehydration reaction between two sugar molecules
