biomolecules Flashcards
what are the 4 biomolecules?
- carbohydrates
- lipids
- proteins
- nucleic acids
what are the 3 components of carbohydrates?
- carbon
- hydrogen
- oxygen
carbohydrates are polymers of ________.
monosaccharides
how many units make up a monosaccharide?
1
how many units make up a disaccharide?
2
how many units make up an oligosaccharide?
3-10
how many units make up a polysaccharide?
more than 10
list 3 types of monosaccharides
- glucose
- fructose
- ribose
list 3 types of disaccharides
- lactose
- sucrose
- maltose
list 3 types of polysaccharides
- starch
- cellulose
- glycogen
which bond holds starch together?
⍺-1,4-glycosidic bond between C1 and C4
where are carbohydrates found in the body?
- muscle
- liver
- blood
how are carbohydrates stored in the muscle and liver?
glycogen
how are carbohydrates stored in the blood?
blood glucose
what are the functions of carbohydrates?
- energy/fuel
- supply carbons for synthesis of cell components (e.g. DNA, RNA)
- form structural components of cells (e.g. glycoproteins, glycolipids)
how is glucose used as fuel for the body and what process allows this?
ATP generation via cellular respiration
how is glycogen used as fuel for the body and what process allows this?
makes glucose via gluconeogenesis
starch is a polymer of ___________.
100s of glucose monomers
what is the main form of starch?
amylose
what is the function of starch?
storage form of excess glucose in plants
gkycogen is a polymer of __________, and has a __________ structure.
100s of glucose monomers; branched
which bond holds together glycogen and gives it the branched structure?
⍺-1,6-glycosidic bond
what is the function of glycogen?
storage form of glucose in mammals
cellulose is a polymer of ___________.
1000s of glucose monomers
what is the function of cellulose?
major structural component of plants
which bond holds together cellulose?
beta 1,4 glycosidic bond
what is the difference between cellulose and starch?
- starch is made up of ⍺-1,4-glycosidic bonds
- cellulose is made up of beta 1,4 glycosidic bonds
what are the roles of lipids?
- energy source
- membrane structure
- animal insulation
- hormone synthesis
- vitamin synthesis
what are the 4 main types of lipids?
- triacylglycerols (TAG) aka triglycerides
- phospholipids
- sterols
- glycolipids
what is the main form of lipid found in the body and the diet?
triacylglycerols
what are the building blocks of triacylglycerols?
- 3 fatty acid chains
- glycerol backbone
what is the structure of a fatty acid?
- long hydrocarbon chain
- carboxylic acid
- methyl group
what is an amphipathic molecule?
a molecule with both hydrophilic and hydrophobic domains
what are the 3 structural factors that determine whether a compound is a solid or liquid?
- HC chain length (long = higher MP; short = lower MP)
- degree of saturation (more unsaturated = lower MP)
- shape (more ‘kinks’ = lower MP)
what is an unsaturated fatty acid?
a fatty acid with one or more double bonds
what is a saturated fatty acid?
a fatty acid with no double bonds
saturated fatty acids are more likely to have a _______ melting point and tend to be more _______.
higher; solid
unsaturated fatty acids have a _______ melting point and tend to be more ______.
lower; liquid
what is a nonessential fatty acid?
a fatty acid that the body can synthesize from the diet
what is an essential fatty acid?
a fatty acid that cannot be synthesized in the body and is required from the diet
what is the structure of a phospholipid?
- 2 fatty acids
- modified phosphate group
- glycerol backbone
which part of the phospholipid is hydrophobic?
lipid tail
which part of the phospholipid is hydrophilic?
phosphate head
what is the function of a phospholipid?
to create a a cell membrane (phospholipid bilayer)
what happens to phospholipids in an aqueous environment?
spontaneously form a bilayer
what are the 3 important phospholipids?
- phosphatidyl choline
- phosphatidyl serine
- phosphatidyl inositol
which phospholipids are involved in cell signaling?
- phosphatidyl choline
- phosphatidyl serine
which phospholipid is involved in apoptosis?
phosphatidyl inositol
what is the least common type of lipid?
sterols
what is the most common sterol?
cholesterol
what are the functions of cholesterol?
- structural component of the cell membrane
- sex hormone synthesis
- vitamin D synthesis
- bile salt synthesis
what is the structure of a glycolipid?
lipid with attached carbohydrate group
what are the functions of a glycolipid?
- cell protection
- immunity to infection
- transplant compatibility
- cell adhesion
what are the elemental components of a protein?
- carbon
- hydrogen
- oxygen
- nitrogen
what differentiates protein from the rest of the macronutrients?
it contains nitrogen
what are proteins composed of?
amino acids
what are the 5 elements that make up amino acids?
- central carbon atom (C)
- side chain (R)
- hydrogen (H)
- nitrogen containing amino group (NH2)
- carboxylic acid group (COOH)
which bond connects amino acids?
peptide bonds between carboxyl group and amine group
what is the sequence of a polypeptide backbone?
N-C-C-N-C-C-N-C-C-N …
what can proteins function as?
- enzymes
- hormones
- receptors
in which biological processes does protein play a role?
- cell structure
- immune system
- transport
- synthesis of other molecules
what are the 3 basic components of a nucleotide?
- phosphate group
- 5 carbon sugar molecule
- base
what are the 5 carbon sugars in a nucleotide?
- deoxyribose (DNA)
- ribose (RNA)
what are the types of bases in a nucleotide?
- purines
- pyrimidines
list the purines
- adenine (A)
- guanine (G)
list the pyrimidines
- cytosine (C)
- thymine (T)
- uracil (U)
which pyrimidine is used only in DNA?
thymine (T)
which pyrimidine is used only in RNA?
uracil (U)
which bond connects nucleotides?
phosphodiester bonds between C5 of one nucleotide and the OH group at C3 of another
which bond is a result of complementary base pairing?
hydrogen bonds
which base pair has the strongest bond in DNA?
guanine and cytosine have 3 bonds
