WorksheetsMOLECULES OF LIFE
Total questions: 20
Worksheet time: 16mins
dehydration
The partially negative charge at one end of one water molecule is attracted to the partially positive charge of another water molecule. What is this attraction called?
a covalent bond.
a hydrogen bond.
an ionic bond.
a hydrophilic bond.
Water is a versatile solvent due to its
low viscosity.
polar molecules.
high specific heat.
high boiling point.
At what temperature is water at its densest?
0°C
4°C
36°C
100°C
Which of the following characteristics of water are essential for the proper functioning of tissue fluid?
I. Water has low viscosity
II. Water has high surface tension
III. Water has maximum density at 4ºC
I only
I and II
II and III
I, II and III
Why are human sex hormones considered to be lipids?
They are essential components of cell membranes.
They are steroids, which are not soluble in water.
They are made of fatty acids.
They are hydrophilic compounds.
Why are phospholipids important to cell structure?
phospholipids are part of DNA.
phospholipids contain fatty acid.
phospholipids have a polar and non-polar end.
phospholipids are found only in animals.
The unique characteristic of each amino acid is determined by
the type of peptide bond.
its position on the polypeptide chain.
its amino group.
its R group
What are the building blocks of nucleic acids?
Amino acids.
Nucleotides.
Pentose sugars.
Phosphate groups.
The phosphodiester linkage in DNA or RNA is formed between
two nitrogenous bases.
two pentose sugars.
a pentose sugar and a nitrogenous base.
a pentose sugar and a phosphate group.
The scientists who proposed the double helix model of DNA are
Singer and Nicholson
Watson and Crick
Meselson and Stahl
Jacob and Monod
A water strider can skate on the surface of a pond because:
covalent bonds result in water cohesion
hydrogen bonds result in water cohesion (surface tension)
water striders have adapted to take advantage of water cohesion
low surface tension of water
