Biology Questions With Complete Solutions
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
, Semmelweis Entrance Exam Medicine
Biology Questions With Complete Solutions
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
What is the basic structure of DNA? it is composed of three parts, a pentose sugar, a phosphate
group and a nitrogenous base
Difference in structure between DNA and RNA RNA contains a ribose sugar instead of
deoxyribose and is also single stranded as well as having Uracil as a base instead of thymine
What are the two double helix strands held together by? hydrogen bonds
What are hydrogen bonds? a special type of dipole-dipole attraction between molecules, not a
covalent bond to a hydrogen atom. It results from the attractive force between a hydrogen atom
, Semmelweis Entrance Exam Medicine
Biology Questions With Complete Solutions
covalently bonded to a very electronegative atom such as a N, O, or F atom and another very
electronegative atom
Why is DNA antiparallel? so that the paired bases can face each other
what is mRNA? Messenger RNA: Encodes amino acid sequence of a polypeptide
What is tRNA? transfer RNA. It carries amino acids around during translation.
What is rRNA? Ribosomal RNA. with ribosomal proteins, makes up the ribosomes, the
organelles that translate the mRNA
what is snRNA? small nuclear RNA. with proteins, forms complexes that are used in RNA
processing in eukaryotes
What are enzymes? biological catalysts. They are globular proteins that can speed up a
biochemical reaction. Alternative pathway
What is glycolysis? the breakdown of glucose by enzymes, releasing energy and pyruvic acid.
What is the kreb's cycle? second stage of cellular respiration, in which pyruvic acid is
broken down into carbon dioxide in a series of energy-extracting reactions
What is the mechanism of ATP production in the mitochondria? located in the inner
mitochondrial membrane, allows the protons to diffuse back across the membrane to the matrix.
ATP synthase uses the energy that the protons release as they diffuse down the concentration
gradient to produce ATP
What is the net yield of ATP in cellular respiration? 38 total
2 in glycolysis