IB Biology Molecules

The gene that codes for a particular polypeptide includes the base sequence shown.

GAGTACCCT

What is the base sequence of the mRNA molecule which is complementary to this sequence?

• GAGTACCCT

• CTCATGGGA

• GUGTUCCCT

• CUCAUGGGA

What type of molecule is formed by the chemical reaction shown in the diagram?

• Dipeptide

• Disaccharide

• Diglyceride

• Cellulose

Which substance must be transported in the blood by lipoprotein complexes?

• Cholesterol

• Oxygen

• Sodium chloride

• Amino acids

What is found in insulin molecules?

• Phosphates

• Nucleotides

• Peptide bonds

• Glycerol

The graph shows the results of an investigation into the activity of turnip peroxidase. The accumulation of the product of the reaction catalysed by the enzyme is shown at different pH values.

Based on the data in the graph, what is most probably the optimum pH for turnip peroxidase?

• Between 3 and 5

• Between 10 and 11

• Between 7 and 8

• Between 9 and 10

Tags

NGSS.HS-PS1-5

Lactose intolerance occurs when the enzyme, lactase, that digests lactose is not produced after infancy in humans. The incidence of lactose intolerance varies in different racial groups. The graph shows the distribution of lactose intolerance in different human populations.

What can be hypothesized from the graph?

• Native American people produce most lactase after infancy.

• Most Indian people do not produce lactase after infancy.

• Lactase is not produced after infancy in most Caucasian people.

• One quarter of Afro-Caribbean people will probably experience digestive problems when drinking milk.

Tags

NGSS.HS-LS3-2

The diagram shows a type of fatty acid.

What type of fatty acid is shown?

• Trans unsaturated

• Cis unsaturated

• Trans saturated

• Cis saturated

Where do hydrogen bonds form?

• Between the slight negative charge of hydrogen and slight positive charge of oxygen within a water molecule

• Between the slight positive charge of hydrogen and slight negative charge of oxygen within a water molecule

• Between the slight positive charge of hydrogen and slight negative charge of oxygen in different water molecules

• Between the slight negative charge of hydrogen and slight positive charge of oxygen in different water molecules

The diagram shows two polysaccharides, formed from condensation of many glucose molecules.

What are the names of X and Y?

• X = glycogen; Y = amylose

• X = amylopectin; Y = amylase

• X = amylase; Y = glycogen

• X = amylose; Y = amylopectin

Which statement correctly describes genome and proteome?

• Only the genome but not the proteome can be analysed using gel electrophoresis.

• The genome and the proteome are the same in all tissues in an organism.

• In cells of different tissues, the genome is the same while the proteome varies.

• Only mutations in the proteome but not in the genome cause any variability.

Tags

NGSS.HS-LS1-1