IB Biology 2.1 - 2.5

Which protein is identified with its function? A: Collagen- Provides strength and support for tissues and organs. B: Rhodopsin- Enzyme found in tears. C: Insulin- Raises blood glucose concentrations. D: Immunoglobulin- Helps in blood clotting

A: Collagen- Provides strength and support for tissues and organs.

Which description matches the protein? A: Collagen- most common structural protein in mammals. B: Rhodopsin- enzyme for carbozylation of RuBP. C: Insulin- raises blood glucose concentration. D: Immunoglobulins- extremely sensitive to light.

A: Collagen- most common structural protein in mammals.

The diagram shows two polysaccharides, formed from condensation of many glucose molecules. What are the names of X and Y? A: x) Glycogen, y) Amylose B: x) Amylopectin, y) Amylase C: x) Amylase, y) Glycogen D: x) Amylose, y) Amylopectin

A: x) Glycogen, y) Amylose

Which type(s) of fatty acid in the diet is/are positively correlated with an increased risk of coronary heart disease? 1: Saturated 2: Trans Unsaturated 3: Cis Unsaturated A: 1 only B: 1 and 2 only C: 2 only D: 2 and 3 only

B: 1 and 2 only

Which process(es) occur(s) by osmosis? 1: Uptake of water by cells in the wall of the intestine. 2: Loss of water from a plant cell in a hypertonic environment. 3: Evaporation of water from sweat on the skin surface. A: 1 only. B: 1 and 2 only. C: 2 and 3 only. D: 1, 2, and 3.

B: 1 and 2 only.

The diagram shows a type of fatty acid. What type of fatty acid is shown? A: Trans Unsaturated. B: Cis Unsaturated. C: Trans Saturated. D: Cis Saturated.

B: Cis Unsaturated

What type of molecule is formed by the chemical reaction shown in the diagram? A: Dipeptide. B: Disaccharide. C: Diglyceride. D: Cellulose.

B: Disaccharide

What is decreased when lactase is added to milk? A: Sweetness. B: Disaccharides. C: Calcium. D: Monosaccharides.

B: Disaccharides

The graph shows the activity of an enzyme at different temperatures. What does the dashed line represent? A:Increasing temperature increases substrate concentration. B: Increasing temperature affects the active site. C: Increasing temperature increases the rate of reaction. D: Increasing temperature decreases movements of particles.

B: Increasing temperature affects the active site.

What feature of carbon makes it most suitable as a basis for life? A: Its abundance in nature. B: Its bonding properties. C: Its reactivity to light. D: Its presence in the early atmosphere of the Earth.

B: Its bonding properties.

Living organisms control pH within their tissues. What is a reason for regulating pH? A: All parts of a body must be kept at the same pH to survive. B: Many reactions can only happen at specific pH levels. C: pH affects osmosis. D: Control of active transport is achieved by pH.

B: Many reactions can only happen at specific pH levels.

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? A: Native American people produce most lactase after infancy. B: Most Indian people do not produce lactase after infancy. C: Lactase is not produced after infancy in most Caucasian people. D: One quarter of Afro-Caribbean people will probably experience digestive problems when drinking milk.

B: Most Indian people do not produce lactase after infancy.

In an experiment the effect of changing pH on an enzymatic reaction is tested. Which could be a dependent variable in this kind of experiment? A: Changing substrate concentration. B: Rate of formation of product. C: Variation in temperature. D: Change in pH.

B: Rate of formation of product.

Which molecule could be hydrolysed into amino acids? A B C D

C

Which molecule represents a lipid.? A B C D

C

The graph shows the result of an investigation into the activity of turnip peroxidase. The accumulation of the product of the reaction catalyze 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. A: Between 3 and 5 B: Between 10 and 11 C: Between 7 and 8 D: Between 9 and 10

C: Between 7 and 8

Where do hydrogen bonds form? A: Between the slight negative charge of hydrogen and slight positive charge of oxygen within a water molecule. B: Between the slight positive charge of hydrogen and slight negative charge of oxygen within a water molecule. C: Between the slight positive charge of hydrogen and slight negative charge of oxygen in different water molecules. D: Between the slight negative charge of hydrogen and slight positive charge of oxygen in different water molecules.

C: Between the slight positive charge of hydrogen and slight negative charge of oxygen in different water molecules.

Three flasks were prepared for an analysis of the activity of the activity of amylase. At time zero, each of the substances indicated in the diagrams was added. Which flask(s) could provide support for the hypothesis that heat denatures enzymes? A: Flask 1 and 2 after 15 minutes. B: Flasks 2 and 3 after 15 minutes. C: Flasks 1 and 3 after 15 minutes D: Flask 3 at time zero and again after 15 minutes.

C: Flasks 1 and 3 after 15 minutes

Which statement correctly describes genome and proteome? A: Only the genome but not the proteome can be analysed using gel ectrophoresis. B: The genome and the proteome are the same in all tissues in an organism. C: In cells of different tissues, the genome is the same while the proteome varies. D: Only mutations in the proteome but not in the genome cause any variability.

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

What is found in insulin molecules? A: Phosphates. B: Nucleotides. C: Peptide bonds. D: Glycerol.

C: Peptide bonds

Which reaction is an example of catabolism? A: Photolysis of water. B: Denaturation of a protein by a change in pH. C: Production of maltose from amylose by amylase. D: Condensation of glucose to form starch.

C: Production of maltose from amylose by amylase.

The graph shows the effect of changing the substrate concentration on the early stages of an enzyme-catalyzed reaction. What can be interpreted about the rate of reaction from the graph? A: Rate of reaction increases up to a point and then remains constant. B: Rate of reaction increases linearly with increasing substrate concentration. C: Rate of reaction increases non-linearly with increasing substrate concentration. D: Rate of reaction is not affected by any change in the substrate concentration.

C: Rate of reaction increases non-linearly with increasing substrate concentration.

Researchers have developed a skin patch which can detect and measure very small concentrations of ions, sugars, amino acids, proteins and hormones which remain when sweat evaporates. What allows the presence of these substances in sweat? A: Cohesion. B: Hydrophobic interactions. C: Solvent properties. D: Thermal properties.

C: Solvent properties.

Which protein has the highest tensile strength (ability to resist breaking when stretched)? A: Cellulose. B: Actin. C: Spider Silk. D: Albumin.

C: Spider Silk

Which fatty acid would occur in a trans fat? A B C D

D

Which type of chemical reaction is an example of anabolism? A: Photolysis. B: Combustion. C: Hydrolysis. D: Condensation.

D: Condensation.

What is the advantage of using lactase in an immobilized state in the food manufacturing industry? A: Changing substrate concentration. B: It dissolves in multiple solvents. C: It converts cellulose into glucose. D: It is less likely to become denatured.

D: It is less likely to become denatured.

Which is an effect of protein denaturation? A: The order of amino acids is changed when the protein overheats. B: The bonds between amino acids are broken by condensation. C: Parts of the protein become linked together by hydrolysis. D: The three-dimensional structure of the protein is altered.

D: The three-dimensional structure of the protein is altered.