AS Level Biology A H020/02 Depth in
biology Monday 4 June 2018 - Afternoon
QUESTIONS AND ANSWERS
1. (a) Fig. 1.1 indicates the general structure of an amino acid
State the names of the corporations labelled U and V - ANSWER-U- amine
organization
V- carboxyl organization
2. * Titin is a fibrous protein. Pepsin is a globular protein. Compare the homes and
capabilities of fibrous proteins and globular proteins in the human frame -
ANSWER-Properties:
Globular-soluble, Fibrous- insoluble
Globular- tertiary structure, fibrous-no tertiary structure
Globular- Hydrophilic R agencies on the outdoor
Fibrous- Hydrophobic R agencies , strong flexible
Functions:
Globular- to transport materials in blood • haemoglobin + role described e.G.
Convey oxygen
to move materials throughout cellular membranes • carrier / channel / pump +
function defined
enzymes / metabolic role / to catalyse reaction(s) / to lower activation power •
named enzyme + its precise function defined
• hormones / receptors / for mobile signaling • named hormone / insulin + position
defined
Fibrous-
for safety • keratin in, skin / hair / nails
for shape • collagen in, bone
to present, elasticity / elastic homes • elastin in, (named) blood vessels / alveoli /
cartilage
3. A cytoskeleton is present in all eukaryotic cells. One of its features is to manipulate the
motion of organelles. State how the cytoskeleton actions organelles around the mobile -
ANSWER-the use of microtubules/ motor proteins
biology Monday 4 June 2018 - Afternoon
QUESTIONS AND ANSWERS
1. (a) Fig. 1.1 indicates the general structure of an amino acid
State the names of the corporations labelled U and V - ANSWER-U- amine
organization
V- carboxyl organization
2. * Titin is a fibrous protein. Pepsin is a globular protein. Compare the homes and
capabilities of fibrous proteins and globular proteins in the human frame -
ANSWER-Properties:
Globular-soluble, Fibrous- insoluble
Globular- tertiary structure, fibrous-no tertiary structure
Globular- Hydrophilic R agencies on the outdoor
Fibrous- Hydrophobic R agencies , strong flexible
Functions:
Globular- to transport materials in blood • haemoglobin + role described e.G.
Convey oxygen
to move materials throughout cellular membranes • carrier / channel / pump +
function defined
enzymes / metabolic role / to catalyse reaction(s) / to lower activation power •
named enzyme + its precise function defined
• hormones / receptors / for mobile signaling • named hormone / insulin + position
defined
Fibrous-
for safety • keratin in, skin / hair / nails
for shape • collagen in, bone
to present, elasticity / elastic homes • elastin in, (named) blood vessels / alveoli /
cartilage
3. A cytoskeleton is present in all eukaryotic cells. One of its features is to manipulate the
motion of organelles. State how the cytoskeleton actions organelles around the mobile -
ANSWER-the use of microtubules/ motor proteins
