BIOLOGY 2025 QUESTIONS AND ANSWERS
What are carbohydrates and lipids? - - correct answer.✔✔ Organic
compounds that are mostly composed of three types of atom; carbon,
hydrogen and oxygen
What do carbohydrates do? - - correct answer.✔✔ 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? - -
correct answer.✔✔ mono-, di- and poly-saccharides
What are mono and disaccharides? - - correct answer.✔✔ polar and soluble
in water
What are polysaccharides? - - correct answer.✔✔ Macromolecules
resulting from polymerisation (condensation) of sugars and are not soluble
in water
Examples of monosaccharides - - correct answer.✔✔ ribose, glucose,
fructose, galactose
What forms a disaccharide? - - correct answer.✔✔ two
monosaccharides linked together by condensation reactions with glycosidic
bonds releasing one H2O molecule
,Examples of Polysaccharides - - correct answer.✔✔ cellulose, glycogen and
starch
Monomer of Sucrose - - correct answer.✔✔ glucose and fructose
monomer of maltose - - correct answer.✔✔ glucose and glucose
monomer of lactose - - correct answer.✔✔ glucose and galactose
monomer of starch - - correct answer.✔✔ glucose
monomer of glycogen - - correct answer.✔✔ glucose
monomer of cellulose - - correct answer.✔✔ glucose
In animals, what carbohydrate stores energy? - - correct answer.✔✔
glycogen
What jobs do carbohydrates have other than storing energy? - - correct
answer.✔✔ structural components
What differs the polysaccharides all made up of glucose? - - correct
answer.✔✔ they differ in the arrangement of glucose molecules and
position of the glycosidic bonds
Starch arrangement - - correct answer.✔✔ amylopectin branched, amylose
linear
, What is galactose? - - correct answer.✔✔ a sugar in milk
What is fructose? - - correct answer.✔✔ a sugar found in fruit and honey
Main characteristic of lipids? - - correct answer.✔✔ little to no affinity to
water, mostly hydrophobic
What are the simple forms of lipids? - - correct answer.✔✔ fat, oil and wax
What are lipids characteristics in different solvents? - - correct
answer.✔✔ they are non-polar and insoluble in water, but soluble in
organic solvents
What are triglycerides? - - correct answer.✔✔ 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? - - correct answer.✔✔ fats
and oils. Fats are solid and oil liquid at room temp
What are fatty acids? - - correct answer.✔✔ carboxylic acids, possessing a -
COOH functional group
What are the two basic forms of fatty acids? - - correct answer.✔✔
saturated and unsaturated