Biology Form 4 Test 2
- 1.
Diagram shows the movement of substances through a plasma membrane. What are substances X and Y?
- A.
X: Sodium ion, Y: Potassium ion
- B.
X: Amino acid , Y: Water
- C.
X: Glucose, Y: Water
- D.
X:Water, Y: Sodium ion
Correct Answer
D. X:Water, Y: Sodium ion -
- 2.
Diagram shows the diffusion of water molecules through a Visking tubing. After one hour, the Visking tubing becomes turgid. What are P and Q?
- A.
P: 20% sucrose solution Q: 20% sucrose solution
- B.
P: 20% sucrose solution Q: 5% sucrose solution
- C.
P: 5% sucrose solution Q: 5% sucrose solution
- D.
P: 5% sucrose solution Q: 20% sucrose solution
Correct Answer
D. P: 5% sucrose solution Q: 20% sucrose solution -
- 3.
Which of the following statement is true about facilitated diffusion? *One or more answers may be correct.
- A.
The process is passive.
- B.
Facilitated diffusion involves carrier protein.
- C.
This process requires expenditure of energy by the cell.
- D.
Facilitated diffusion does not occur in the presence of respiratory poison.
Correct Answer(s)
A. The process is passive.
B. Facilitated diffusion involves carrier protein.Explanation
Facilitated diffusion is a passive process, meaning it does not require the cell to expend energy. It involves the use of carrier proteins to transport molecules across the cell membrane.Rate this question:
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- 4.
Sample strips of potato tissue were placed in different concentrations of a sucrose solution. The mass of potato strips at the beginning and at the end of the experiment are recorded in diagram below. Based on the diagram, which concentration would be hypertonic to the potato cells?
- A.
10%
- B.
20%
- C.
25%
- D.
35%
Correct Answer
D. 35%Explanation
In the diagram, it can be observed that the mass of the potato strips decreased when placed in the 35% concentration of sucrose solution. This indicates that water moved out of the potato cells, causing them to shrink. This suggests that the concentration of the sucrose solution is higher than the concentration of solutes inside the potato cells, making the 35% concentration hypertonic to the potato cells.Rate this question:
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- 5.
Active transport is the movement of
- A.
Molecules from a region of their higher concentration to a region of their lower concentration.
- B.
Particles from a region of lower concentration to a region of higher concentration using energy from respiration.
- C.
Urine by relaxation of a sphincter muscle in the bladder
- D.
Water through a partially permeable membrane from a more dilute to a more concentrated solution.
Correct Answer
B. Particles from a region of lower concentration to a region of higher concentration using energy from respiration.Explanation
Active transport is the process by which particles are moved from a region of lower concentration to a region of higher concentration. This movement requires energy, which is obtained from respiration. Unlike passive transport, which relies on concentration gradients, active transport allows cells to transport molecules against their concentration gradient, ensuring that essential substances are taken up and waste products are expelled. This process is crucial for maintaining homeostasis and ensuring the proper functioning of cells and organisms.Rate this question:
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- 6.
The diagram shows an experiment to demonstrate the movement of molecules. After one hour, the water in the beaker turned red. What is the most likely reason for this colour change?
- A.
Molecules of red ink move through the membrane by diffusion.
- B.
Molecules of red ink move through the membrane by osmosis
- C.
Molecules of water move through the membrane by diffusion
- D.
Molecules of water move through the membrane by osmosis.
Correct Answer
A. Molecules of red ink move through the membrane by diffusion.Explanation
The most likely reason for the color change in the water is that molecules of red ink moved through the membrane by diffusion. This means that the red ink molecules moved from an area of higher concentration (the red ink solution) to an area of lower concentration (the water in the beaker) until equilibrium was reached. This movement of molecules is characteristic of diffusion, where particles move from an area of high concentration to an area of low concentration. Osmosis, on the other hand, refers specifically to the movement of water molecules through a selectively permeable membrane, so it is not the most likely reason for the color change in this scenario.Rate this question:
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- 7.
Why does oxygen diffuse into the blood from an alveolus in the lungs?
- A.
The oxygen concentration in the alveolus is greater than the carbon dioxide concentration in the blood.
- B.
The oxygen concentration in the alveolus is greater than in the blood
- C.
The oxygen concentration in the blood is greater than in the alveolus.
- D.
The oxygen concentration in the blood is greater than the carbon dioxide concentration in the alveolus.
Correct Answer
B. The oxygen concentration in the alveolus is greater than in the bloodExplanation
Oxygen diffuses into the blood from an alveolus in the lungs because the oxygen concentration in the alveolus is greater than in the blood. This concentration gradient allows oxygen molecules to move from an area of high concentration (alveolus) to an area of low concentration (blood) through diffusion.Rate this question:
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- 8.
A jar of air was placed upside down on top of a jar containing a brown gas as shown. Which process has taken place?
- A.
Diffusion both upwards and downwards
- B.
Diffusion downwards only
- C.
Diffusion upwards only
- D.
Diffusion and osmosis
Correct Answer
A. Diffusion both upwards and downwardsExplanation
The jar of air being placed upside down on top of the jar containing the brown gas allows for diffusion to occur in both directions. Diffusion is the movement of particles from an area of high concentration to an area of low concentration. In this case, the air particles in the jar will move downwards into the jar containing the brown gas, while the brown gas particles will move upwards into the jar of air. Therefore, diffusion is happening both upwards and downwards.Rate this question:
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- 9.
Which statement describes how young plants are supported?
- A.
The pressure of water inside the cells pressing outwards on the cell membranes
- B.
The pressure of water inside the cells pressing outwards on the cell walls
- C.
The pressure of water passing from the roots through the phloem
- D.
The pressure of water passing from the roots through the xylem
Correct Answer
B. The pressure of water inside the cells pressing outwards on the cell wallsExplanation
Young plants are supported by the pressure of water inside the cells pressing outwards on the cell walls. This pressure, known as turgor pressure, helps to maintain the shape and rigidity of the plant cells, providing support for the growing plant.Rate this question:
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- 10.
A student cuts out four pieces of carrot root of equal size. The pieces are treated as shown in the diagram, and then left for two hours. After two hours, which piece of carrot will be the smallest?
- A.
Option 1
- B.
Option 2
- C.
Option 3
- D.
Option 4
Correct Answer
C. Option 3Explanation
The diagram shows that each piece of carrot root is treated differently. Option 3 is the piece that is boiled for two hours. Boiling carrots for a long time causes them to become soft and lose their shape, so the boiled carrot will likely be the smallest piece after two hours.Rate this question:
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- 11.
Which statements are correct for both diffusion and osmosis? *One or more answers may be correct.
- A.
Involves movement of water only
- B.
Requires energy from the cell
- C.
Molecules move from higher concentration to lower concentration
- D.
Require a partially permeable membrane
- E.
Require a concentration gradient
Correct Answer(s)
C. Molecules move from higher concentration to lower concentration
E. Require a concentration gradientExplanation
Both diffusion and osmosis involve the movement of molecules from an area of higher concentration to an area of lower concentration. This is known as moving down the concentration gradient. Therefore, the statements "molecules move from higher concentration to lower concentration" and "require a concentration gradient" are correct for both diffusion and osmosis.Rate this question:
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- 12.
A human cell contains a length of DNA that carries the code for making which substance?
- A.
Fat
- B.
Glycogen
- C.
Lipase
- D.
Starch
Correct Answer
C. LipaseExplanation
Lipase is an enzyme that breaks down fats into smaller molecules. DNA carries the code for making various substances in the body, including enzymes like lipase. Therefore, lipase is the correct answer as it is the substance that is coded for by the DNA in a human cell.Rate this question:
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- 13.
Water is a good solvent. What does this mean?
- A.
It dissolves well in many other substances.
- B.
It flows easily through vessels.
- C.
It is permeable to gases.
- D.
Many substances dissolve well in it.
Correct Answer
D. Many substances dissolve well in it.Explanation
Water is considered a good solvent because it has the ability to dissolve many substances. This is due to its unique molecular structure, which allows it to form hydrogen bonds with other molecules. These hydrogen bonds help to break apart the solute particles and surround them, dispersing them evenly throughout the water. As a result, water can dissolve a wide variety of substances, making it an effective solvent in many chemical reactions and biological processes.Rate this question:
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- 14.
List three elements present in carbohydrates. ________,________ and ________.
Correct Answer
carbon, hydrogen, oxygen
carbon, hydrogen, oxygen
carbon, hydrogen, oxygenExplanation
The correct answer is carbon, hydrogen, and oxygen. Carbohydrates are organic compounds composed of these three elements. Carbon forms the backbone of the carbohydrate molecule, while hydrogen and oxygen are present in the same ratio as water (H2O). These elements are essential for the structure and function of carbohydrates, which serve as a major source of energy in living organisms.Rate this question:
- 15.
What is the basic monomer unit of proteins?________
Correct Answer
amino acids, amino acidExplanation
Proteins are composed of long chains of amino acids, which are the basic monomer units of proteins. Amino acids are organic compounds that contain both an amino group (-NH2) and a carboxyl group (-COOH). They are joined together through peptide bonds to form polypeptide chains, which then fold into specific 3D structures to create proteins. Therefore, the correct answer is amino acids or amino acid.Rate this question:
- 16.
Amino acid + amino acid → ________+ water
Correct Answer
dipeptide, dipeptidesExplanation
When two amino acids combine, they form a dipeptide. A dipeptide is a molecule composed of two amino acids joined together by a peptide bond. The formation of a dipeptide involves the removal of a water molecule, a process known as condensation or dehydration synthesis. Therefore, the given equation represents the reaction where two amino acids combine to form a dipeptide and release water as a byproduct. The term "dipeptides" is used to refer to multiple dipeptide molecules.Rate this question:
- 17.
The basic unit composition of fat is
- A.
three molecules of glycerol
- B.
Three molecules of fatty acids
- C.
Three molecules of glycerol and one molecule of fatty acid
- D.
One molecule of glycerol and three molecules of fatty acids
Correct Answer
D. One molecule of glycerol and three molecules of fatty acidsExplanation
The basic unit composition of fat is one molecule of glycerol and three molecules of fatty acids. This means that when fats are broken down, they are composed of one glycerol molecule and three fatty acid molecules.Rate this question:
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- 18.
Which of the following is an example of protein?
- A.
Steroids
- B.
Silk
- C.
Waxes
- D.
Glycogen
Correct Answer
B. SilkExplanation
Silk is an example of a protein because it is produced by certain insects, such as silkworms, as a fibrous protein called fibroin. This protein is spun into silk threads to create cocoons. Proteins are large molecules made up of amino acids and have a wide range of functions in living organisms, including structural support, enzymatic activity, and transportation of molecules. Steroids, waxes, and glycogen are not proteins, as they have different chemical structures and functions.Rate this question:
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- 19.
If Y is a sucrose, write the word equation for process P. Process P: ________ + ________—> ________ +________
Correct Answer
sucrose,water
sucrose,water
glucose,fructose
glucose,fructoseExplanation
In process P, sucrose is broken down into its constituent parts, glucose and fructose, through the addition of water. Therefore, the word equation for process P is "sucrose + water -> glucose + fructose".Rate this question:
- 20.
There are ________ naturally-occurring amino acids. [write your answers in numbers only, not in words]
Correct Answer
20Explanation
The question asks for the number of naturally-occurring amino acids. Amino acids are the building blocks of proteins and there are 20 different amino acids that are commonly found in living organisms. Each amino acid has a unique side chain, which gives it different properties and functions. Therefore, the correct answer is 20.Rate this question:
- 21.
Write the mRNA sequence from this DNA template [without any space in between.] T A C T T C C T A T T T C A T G TA ________
Correct Answer
AUGAAGGAUAAAGUACAUExplanation
The given DNA template sequence is TACTTCCCTATTTTCATGTA. In DNA, T (thymine) pairs with A (adenine), A pairs with T, C (cytosine) pairs with G (guanine), and G pairs with C. Therefore, the mRNA sequence will have complementary bases, replacing T with U (uracil). So, the mRNA sequence is AUGAAGGAUAAAGUACAU.Rate this question:
- 22.
How many amino acids long polypeptide chain will be formed from the mRNA sequence you wrote from the previous question? Write answer in number form.
Correct Answer
6 - 23.
This fat *One or more answers may be correct.
- A.
Exsits in solid forrn at room temperature.
- B.
Has a lower melting point.
- C.
Derived from animal sources.
- D.
Fatty acids have double bonds between the carbon atoms
Correct Answer(s)
A. Exsits in solid forrn at room temperature.
C. Derived from animal sources. -
- 24.
Diagram below shows the mechanism of enzymatic action.What are the conclusions that can be deduced from diagram below? *One or more answers may be correct.
- A.
The optimum temperature for enzymatic reaction is 40 ºC
- B.
The enzymatic action is specific.
- C.
The enzyme is not destroyed at the end of the reaction.
- D.
The enzymatic reaction is reversible.
Correct Answer(s)
B. The enzymatic action is specific.
C. The enzyme is not destroyed at the end of the reaction.Explanation
From the diagram, it can be deduced that the enzymatic action is specific because the enzyme is shown to interact with a specific substrate. Additionally, it can be concluded that the enzyme is not destroyed at the end of the reaction because it is shown to be separate from the product. However, the diagram does not provide information about the optimum temperature for enzymatic reaction or whether the enzymatic reaction is reversible.Rate this question:
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- 25.
Which of the following graphs best represents the effect of pH on the rate of reaction of enzymes in the duodenum ?
- A.
Option 1
- B.
Option 2
- C.
Option 3
- D.
Option 4
Correct Answer
C. Option 3Explanation
Option 3 is the best representation of the effect of pH on the rate of reaction of enzymes in the duodenum because it shows an increase in enzyme activity as the pH increases from acidic to slightly alkaline levels, reaching an optimal pH where the reaction rate is highest. After the optimal pH, the enzyme activity decreases as the pH becomes more alkaline. This graph demonstrates the typical bell-shaped curve that represents the relationship between pH and enzyme activity.Rate this question:
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- 26.
Diagram below shows the relationship between the rate of reaction and substrate concentration when factor P is varied. Factor P is
- A.
Time
- B.
PH
- C.
Temperature
- D.
Enzyme concentration
Correct Answer
D. Enzyme concentrationExplanation
The diagram shows the relationship between the rate of reaction and substrate concentration when a factor P is varied. The options given are time, pH, temperature, and enzyme concentration. From the diagram, it can be observed that as the enzyme concentration increases, the rate of reaction also increases. This suggests that factor P is the enzyme concentration, as it directly affects the rate of reaction.Rate this question:
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- 27.
The diagram represents a chemical reaction. Which diagram represents the enzyme for this reaction?
- A.
Option 1
- B.
Option 2
- C.
Option 3
- D.
Option 4
Correct Answer
D. Option 4Explanation
Option 4 represents the enzyme for this reaction because it shows a specific protein structure that is responsible for catalyzing the chemical reaction. The other options do not show any protein structure or do not accurately represent an enzyme.Rate this question:
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- 28.
The diagram shows an experiment on the digestion of the protein in egg albumen by protease. The protease was taken from a human stomach. In which test-tube will the protein be digested most quickly?
- A.
Test-tube A
- B.
Test-tube B
- C.
Test-tube C
- D.
Test-tube D
Correct Answer
C. Test-tube CExplanation
Protease is an enzyme that breaks down proteins. The diagram shows that the protease used in the experiment was taken from a human stomach. The stomach is known to have a highly acidic environment, which is ideal for the activity of protease enzymes. Test-tube C, which contains the protease from a human stomach, is likely to have the most acidic environment compared to the other test-tubes. Therefore, the protein in test-tube C will be digested most quickly due to the optimal conditions for the protease enzyme.Rate this question:
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- 29.
What is/are the characteristics of all catalysts? *One or more answers may be correct.
- A.
They are broken down in the reaction.
- B.
They speed up biochemical reactions
- C.
They are not changed by the reaction.
- D.
They do not change the rate of the reaction
Correct Answer(s)
B. They speed up biochemical reactions
C. They are not changed by the reaction.Explanation
Catalysts are substances that speed up biochemical reactions without being consumed or changed by the reaction. This means that they remain unchanged at the end of the reaction and can be used again. Therefore, the characteristics of all catalysts are that they speed up biochemical reactions and they are not changed by the reaction.Rate this question:
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- 30.
Two enzyme-controlled reactions are shown. From these reactions, what deduction can be made about enzymes?
- A.
Enzyme 1 has been changed to enzyme 2.
- B.
Enzyme 2 slows down the production of amino acids.
- C.
Enzymes can build up large molecules.
- D.
Enzymes only break down large molecules
Correct Answer
C. Enzymes can build up large molecules.Explanation
The deduction that can be made about enzymes from the given information is that enzymes can build up large molecules. This can be inferred from the fact that when enzyme 1 is changed to enzyme 2, it slows down the production of amino acids. This suggests that enzyme 2 is involved in the synthesis or building up of amino acids, which are large molecules.Rate this question:
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- 31.
In an experiment, the effect of temperature on the action of amylase is investigated. Six different test-tubes are set up, each containing a mixture of amylase and starch solution. Which condition should be kept the same in each of the six test-tubes? *One or more answers may be correct.
- A.
Concentration of amylase
- B.
PH
- C.
Temperature
- D.
Volume of starch solution
Correct Answer(s)
A. Concentration of amylase
B. pH
D. Volume of starch solutionExplanation
In order to accurately investigate the effect of temperature on the action of amylase, it is important to keep certain conditions the same in each of the six test-tubes. The concentration of amylase should be kept the same to ensure that any observed differences in the reaction are solely due to the temperature variation and not because of differences in enzyme concentration. The pH should also be kept the same as it can affect the activity of the enzyme. Additionally, the volume of starch solution should be kept the same to ensure that the enzyme-substrate ratio remains constant across all test-tubes.Rate this question:
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- 32.
The apparatus shown in the diagram was used for an experiment on starch digestion. Which tube would contain most sugar after 20 minutes?
- A.
Tube A
- B.
Tube B
- C.
Tube C
- D.
Tube D
Correct Answer
D. Tube DExplanation
Tube D would contain the most sugar after 20 minutes because it contains both the enzyme amylase and the substrate starch. Amylase is responsible for breaking down starch into sugar molecules, so having both the enzyme and substrate present in tube D would result in the highest amount of sugar being produced.Rate this question:
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- 33.
Diagram shows the condition of a plant cell after being immersed in solution Y for 20 minutes. Which of the following is the correct answer for Z and solution Y?
- A.
Z: Air ,Solution Y: Isotonic solution
- B.
Z: Water, Solution Y: Hypotonic solution
- C.
Z: Solution Y, Solution Y: Hypertonic solution
- D.
Z: Vacuum, Solution Y: Isotonic solution
Correct Answer
C. Z: Solution Y, Solution Y: Hypertonic solution -
- 34.
Diagram shows part of a plasma membrane. What are the parts labelled I and II? I: ________ II: ________ Fill in the blanks with the words given. Hydrophilic head Hydrophobic head Hydrophilic tail Hydrophobic tail
Correct Answer
Hydrophilic head
Hydrophobic tail
Hydrophobic tailExplanation
The diagram shows a plasma membrane, which consists of a phospholipid bilayer. The phospholipids have a hydrophilic head and hydrophobic tail. The hydrophilic head is attracted to water and faces the aqueous environment both inside and outside of the cell. The hydrophobic tail is repelled by water and is sandwiched between the hydrophilic heads, creating a barrier that prevents water-soluble molecules from freely passing through the membrane. Therefore, the parts labelled I and II correspond to the hydrophilic head and hydrophobic tail, respectively.Rate this question:
- 35.
Diagram below shows one way of preserving vegetable. Which of the following explain why the vegetables can last longer?
- A.
The low pH is not conducive for bacterial growth.
- B.
The vinegar causes the vegetable to turn alkaline.
- C.
The water molecules diffuse into the vegetable.
- D.
The bacteria are deplasmolysed.
Correct Answer
A. The low pH is not conducive for bacterial growth.Explanation
The low pH of the preserved vegetable creates an environment that is not suitable for bacterial growth. Bacteria require a neutral or slightly alkaline environment to thrive, and the acidity of the low pH inhibits their growth. This helps to prevent spoilage and allows the vegetables to last longer.Rate this question:
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- 36.
A stalk of mustard green is cut longitudinally into four equal strips. All the strips were immersed for 30 minutes in sucrose solution of different concentrations. Which strip was immersed in hypotonic solutions?
- A.
Option 1
- B.
Option 2
- C.
Option 3
- D.
Option 4
Correct Answer
D. Option 4Explanation
The strip immersed in the hypotonic solution would have absorbed water and become swollen. In a hypotonic solution, the concentration of solutes outside the cell is lower than inside the cell, causing water to move into the cell by osmosis. Therefore, the strip in Option 4 would have been immersed in the hypotonic solution.Rate this question:
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- 37.
Diagram below shows a sequence of a strip of mustard green stem that is immersed in two different solutions, 1.0 M sucrose solution and distilled water. What are processes X and Y? X: ________ Y: ________ Fill in the blanks with the words given. Deplasmolysis Crenation Plasmolysis Haemolysis
Correct Answer
Plasmolysis
DeplasmolysisExplanation
The process X in the given diagram is plasmolysis, which is the shrinkage or contraction of the protoplasm of a plant cell due to the loss of water through osmosis. The process Y is deplasmolysis, which is the reverse process of plasmolysis, where the protoplasm of a plant cell regains water and returns to its original state.Rate this question:
- 38.
Diagram below shows the condition of a plant after being given some fertiliser. Which of the following explain the phenomena?*One or more answers may be correct.
- A.
Water diffuses from the soil into the cell sap by osmosis.
- B.
The plant loses water and this causes the cells to become plasmolysed.
- C.
Fertilisers dissolved in the soil water and causes it to become more concentrated and hypertonic to the cell sap of the roots.
- D.
Fertilisers dissolved in the soil water and causes it to become less concentrated and hypotonic to the cell sap of the roots.
Correct Answer(s)
B. The plant loses water and this causes the cells to become plasmolysed.
C. Fertilisers dissolved in the soil water and causes it to become more concentrated and hypertonic to the cell sap of the roots.Explanation
When fertilizers are dissolved in the soil water, they increase the concentration of solutes in the water. This increased concentration makes the soil water hypertonic compared to the cell sap in the roots. As a result, water diffuses out of the plant cells through osmosis, causing the plant to lose water. This loss of water leads to the cells becoming plasmolysed, which means that the cytoplasm shrinks away from the cell wall. Therefore, both statements explain the phenomena observed in the diagram.Rate this question:
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- 39.
In an experiment, several pieces of potato were placed in sucrose solution of different concentrations. The mass changed were then plotted onto graphs. Which graph shows the mass changes correctly?
- A.
Option 1
- B.
Option 2
- C.
Option 3
- D.
Option 4
Correct Answer
D. Option 4Explanation
Option 4 shows the mass changes correctly because as the concentration of sucrose solution increases, the mass of the potato decreases. This is evident from the negative slope of the graph in Option 4. The other options either show incorrect relationships between concentration and mass or do not show any clear trend.Rate this question:
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- 40.
Diagram below shows the experiment to study the activity of salivary amylase. Which of the following curves represents the result of the experiment?
- A.
A
- B.
B
- C.
C
- D.
D
Correct Answer
D. DExplanation
Curve D represents the result of the experiment because it shows an increase in the activity of salivary amylase over time. This is indicated by the upward slope of the curve. Curves A, B, and C either show a decrease in activity or no change in activity, which is not consistent with the experiment. Therefore, curve D is the correct representation of the experiment's result.Rate this question:
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- 41.
A housewife uses a few slices of unripe papaya to tenderize the meat she is cooking for dinner. Which of the following sequences is correct? P Add the raw papaya slices Q Boil the meat R Leave the meat for one and a half hour S Cut the meat into small pieces
- A.
Q → R → S → P
- B.
S → P → R → Q
- C.
P → Q → R → S
- D.
R → S → Q → P
Correct Answer
B. S → P → R → QExplanation
The correct sequence is S → P → R → Q. First, the housewife cuts the meat into small pieces (S). Then, she adds the raw papaya slices to tenderize the meat (P). After that, she leaves the meat for one and a half hours (R) to allow the papaya to work its tenderizing magic. Finally, she boils the meat (Q) to cook it for dinner.Rate this question:
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- 42.
Diagram below shows the molecular structure of two classes of food. What are the food classes of P and Q? P :________ Q: ________ Fill in the blanks with the words given. Carbohydrate Protein Lipid
Correct Answer
Protein
LipidExplanation
The molecular structure of P corresponds to a protein, while the molecular structure of Q corresponds to a lipid.Rate this question:
- 43.
The following information refers to the function of substance K in cell. ● Medium for biochemical reactions in cells ● Maintaining osmotic pressure of cells What is substance K?
- A.
Lipid
- B.
Water
- C.
Protein
- D.
Enzyme
Correct Answer
B. WaterExplanation
Water is the substance K in the cell because it acts as a medium for biochemical reactions in cells and helps maintain the osmotic pressure of cells. Water is essential for various cellular processes, such as transportation of nutrients, removal of waste, and facilitating chemical reactions. It is also involved in maintaining the shape and structure of cells.Rate this question:
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- 44.
The statement describes a characteristic of enzyme maltase. ‘Maltase can speed up both the hydrolysis and condensation process’. Which of the following refers to the characteristic above?
- A.
Specific in action
- B.
Reversible reaction
- C.
Required in small quantity
- D.
Not destroyed after reaction
Correct Answer
B. Reversible reactionExplanation
The characteristic described in the statement is that maltase can speed up both the hydrolysis and condensation process. This implies that the reaction catalyzed by maltase can proceed in both directions, meaning it is reversible.Rate this question:
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- 45.
Diagram below shows a shirt with a blood stain before and after being washed with detergent containing enzyme.Which are the most suitable enzyme and temperature to give the result shown?
- A.
Lipase 37°C
- B.
Protease 18°C
- C.
Lipase 18°C
- D.
Protease 37°C
Correct Answer
D. Protease 37°C -
- 46.
Diagram shows the structure of DNA. What are P, Q and R? P: ________ Q: ________ R: ________ Fill in the blanks with the words given. Nucleotide Phosphate group Nitrogenous base Deoxyribose sugar Ribose sugar
Correct Answer
Phosphate group
Deoxyribose sugar
Nitrogenous baseExplanation
P is the Phosphate group, Q is the Deoxyribose sugar, and R is the Nitrogenous base. These are the components that make up a nucleotide, which is the building block of DNA. The phosphate group provides the backbone of the DNA molecule, the deoxyribose sugar forms the sides of the DNA ladder, and the nitrogenous base pairs with another base to form the rungs of the DNA ladder. Together, these components create the structure of DNA.Rate this question:
- 47.
Which of these carbohydrates is soluble in water?*One or more answers may be correct.
- A.
Starch
- B.
Maltose
- C.
Glucose
- D.
Galactose
Correct Answer(s)
B. Maltose
C. Glucose
D. GalactoseExplanation
Maltose, glucose, and galactose are all soluble in water because they are all monosaccharides or disaccharides. These types of carbohydrates have hydrophilic functional groups, such as hydroxyl groups, that can form hydrogen bonds with water molecules, allowing them to dissolve in water. Starch, on the other hand, is a polysaccharide made up of many glucose units and is insoluble in water.Rate this question:
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- 48.
Which of the following are extracellular enzymes? *One or more answers may be correct.
- A.
Amylase
- B.
Pepsin
- C.
Trypsin
Correct Answer(s)
A. Amylase
B. Pepsin
C. TrypsinExplanation
Extracellular enzymes are enzymes that are secreted outside of the cell and function in the extracellular environment. Amylase, pepsin, and trypsin are all examples of extracellular enzymes. Amylase is produced in the salivary glands and pancreas and functions in the breakdown of carbohydrates. Pepsin is produced in the stomach and aids in the digestion of proteins. Trypsin is produced in the pancreas and also aids in protein digestion. These enzymes are released into the digestive system to break down food molecules into smaller, more easily absorbed components.Rate this question:
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- 49.
Diagram shows structure protein A and structure protein B. State the factors that affect the changes of structure protein A to structure protein B. *One or more answers may be correct.
- A.
PH
- B.
Temperature
- C.
Salt concentration
- D.
Humidity
Correct Answer(s)
A. pH
B. TemperatureExplanation
The factors that affect the changes of structure protein A to structure protein B are pH and temperature. pH refers to the acidity or alkalinity of the environment and can alter the charges on amino acid residues, affecting the protein's structure. Temperature can denature proteins by disrupting the weak bonds that stabilize their structure. Salt concentration and humidity are not mentioned as factors that affect the changes in protein structure in the given information.Rate this question:
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- 50.
Diagram below shows the organelles in an animal cell. Which of the organelles P, Q, R and S are involved in the synthesis and secretion of extracellular enzymes? *One or more answers may be correct.
- A.
P
- B.
Q
- C.
R
- D.
S
Correct Answer(s)
B. Q
C. R
D. SExplanation
Organelles Q, R, and S are involved in the synthesis and secretion of extracellular enzymes. Organelle Q is likely the endoplasmic reticulum (ER), which is responsible for protein synthesis and modification. Organelle R is likely the Golgi apparatus, which receives proteins from the ER and further modifies and packages them for secretion. Organelle S is likely the secretory vesicles, which transport the packaged enzymes to the cell membrane for secretion. Therefore, organelles Q, R, and S are involved in the synthesis and secretion of extracellular enzymes.Rate this question:
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Mar 21, 2023Quiz Edited by
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May 10, 2020Quiz Created by
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