Semmelweis Entrance Exam Medicine Biology 2023 Guide
with complete solution
What are carbohydrates and lipids?
Organic compounds that are mostly composed of three types of atom; carbon, hydrogen
and oxygen
What do carbohydrates do?
provide energy, in the form of sugars like glucose and fructose, but they also make up
structures like cellulose, which form the cell wall of plant cells
What type of carbohydrate is the most important source of energy?
mono-, di- and poly-saccharides
What are mono and disaccharides?
polar and soluble in water
What are polysaccharides?
Macromolecules resulting from polymerisation (condensation) of sugars and are not
soluble in water
Examples of monosaccharides
ribose, glucose, fructose, galactose
What forms a disaccharide?
two monosaccharides linked together by condensation reactions with glycosidic bonds
releasing one H2O molecule
Alpha glucose structure
Beta glucose structure
Examples of Polysaccharides
cellulose, glycogen and starch
Monomer of Sucrose
glucose and fructose
monomer of maltose
glucose and glucose
monomer of lactose
glucose and galactose
monomer of starch
glucose
monomer of glycogen
glucose
, monomer of cellulose
glucose
In animals, what carbohydrate stores energy?
glycogen
What jobs do carbohydrates have other than storing energy?
structural components
What differs the polysaccharides all made up of glucose?
they differ in the arrangement of glucose molecules and position of the glycosidic bonds
Starch arrangement
amylopectin branched, amylose linear
What is galactose?
a sugar in milk
What is fructose?
a sugar found in fruit and honey
Main characteristic of lipids?
little to no affinity to water, mostly hydrophobic
What are the simple forms of lipids?
fat, oil and wax
What are lipids characteristics in different solvents?
they are non-polar and insoluble in water, but soluble in organic solvents
What are triglycerides?
the main group of lipids. They are formed by condensation reactions between one
glycerol and three fatty acids, creating ester bonds
What are the main types of triglycerides?
fats and oils. Fats are solid and oil liquid at room temp
What are fatty acids?
carboxylic acids, possessing a -COOH functional group
What are the two basic forms of fatty acids?
saturated and unsaturated
What differs saturated from unsaturated fatty acids?
Unsaturated fatty acids have double bonds; a monounsaturated having one, whereas a
polyunsaturated having multiple
What are cis and trans isomers?
cis having the double bond elements on the same side, trans on opposite
Benefit of lipids over carbohydrates?
Lipids have a higher energy content and can act as thermal insulators
What is the primary protein structure?
the number and sequence of amino acids in a polypeptide
What is the secondary protein structure?
Beta pleated sheet and alpha helix. Hydrogen bonds between polypeptides form these
structures
What is the tertiary protein structure?
three dimensional conformation. Forms when a polypeptide folds up after translation.
Stabilized by intramolecular bonds between amino acids and polypeptides
What is the quaternary protein structure?
linking two or more polypeptides to form a single protein
with complete solution
What are carbohydrates and lipids?
Organic compounds that are mostly composed of three types of atom; carbon, hydrogen
and oxygen
What do carbohydrates do?
provide energy, in the form of sugars like glucose and fructose, but they also make up
structures like cellulose, which form the cell wall of plant cells
What type of carbohydrate is the most important source of energy?
mono-, di- and poly-saccharides
What are mono and disaccharides?
polar and soluble in water
What are polysaccharides?
Macromolecules resulting from polymerisation (condensation) of sugars and are not
soluble in water
Examples of monosaccharides
ribose, glucose, fructose, galactose
What forms a disaccharide?
two monosaccharides linked together by condensation reactions with glycosidic bonds
releasing one H2O molecule
Alpha glucose structure
Beta glucose structure
Examples of Polysaccharides
cellulose, glycogen and starch
Monomer of Sucrose
glucose and fructose
monomer of maltose
glucose and glucose
monomer of lactose
glucose and galactose
monomer of starch
glucose
monomer of glycogen
glucose
, monomer of cellulose
glucose
In animals, what carbohydrate stores energy?
glycogen
What jobs do carbohydrates have other than storing energy?
structural components
What differs the polysaccharides all made up of glucose?
they differ in the arrangement of glucose molecules and position of the glycosidic bonds
Starch arrangement
amylopectin branched, amylose linear
What is galactose?
a sugar in milk
What is fructose?
a sugar found in fruit and honey
Main characteristic of lipids?
little to no affinity to water, mostly hydrophobic
What are the simple forms of lipids?
fat, oil and wax
What are lipids characteristics in different solvents?
they are non-polar and insoluble in water, but soluble in organic solvents
What are triglycerides?
the main group of lipids. They are formed by condensation reactions between one
glycerol and three fatty acids, creating ester bonds
What are the main types of triglycerides?
fats and oils. Fats are solid and oil liquid at room temp
What are fatty acids?
carboxylic acids, possessing a -COOH functional group
What are the two basic forms of fatty acids?
saturated and unsaturated
What differs saturated from unsaturated fatty acids?
Unsaturated fatty acids have double bonds; a monounsaturated having one, whereas a
polyunsaturated having multiple
What are cis and trans isomers?
cis having the double bond elements on the same side, trans on opposite
Benefit of lipids over carbohydrates?
Lipids have a higher energy content and can act as thermal insulators
What is the primary protein structure?
the number and sequence of amino acids in a polypeptide
What is the secondary protein structure?
Beta pleated sheet and alpha helix. Hydrogen bonds between polypeptides form these
structures
What is the tertiary protein structure?
three dimensional conformation. Forms when a polypeptide folds up after translation.
Stabilized by intramolecular bonds between amino acids and polypeptides
What is the quaternary protein structure?
linking two or more polypeptides to form a single protein
