Q. What is the basic unit of heredity in living organisms?
A.Chromosome
B.Gene
C.DNA
D.RNA
Solution
A gene is the basic unit of heredity, responsible for the transmission of traits from parents to offspring.
Correct Answer: B — Gene
Q. What is the basic unit of heredity in Mendelian genetics?
A.Chromosome
B.Gene
C.DNA
D.RNA
Solution
A gene is the basic unit of heredity, responsible for the transmission of traits from parents to offspring.
Correct Answer: B — Gene
Q. What is the D-value for a microorganism if it takes 5 minutes to reduce the population by 90% at 121°C?
A.1 minute
B.2 minutes
C.5 minutes
D.10 minutes
Solution
The D-value is the time required to reduce the microbial population by 90%, which in this case is 5 minutes.
Correct Answer: C — 5 minutes
Q. What is the effect of increased carbon dioxide concentration on photosynthesis?
A.Decreases rate
B.Increases rate
C.No effect
D.Stops photosynthesis
Solution
Increased carbon dioxide concentration generally increases the rate of photosynthesis, up to a certain point.
Correct Answer: B — Increases rate
Q. What is the effect of increased light intensity on the rate of photosynthesis, assuming other factors are optimal?
A.Decreases rate
B.Increases rate
C.No effect
D.Stops photosynthesis
Solution
Increased light intensity generally increases the rate of photosynthesis, up to a certain point.
Correct Answer: B — Increases rate
Q. What is the effect of increased light intensity on the rate of photosynthesis, assuming other factors are constant?
A.Decreases rate
B.Increases rate
C.No effect
D.Stops photosynthesis
Solution
Increased light intensity generally increases the rate of photosynthesis, up to a certain point.
Correct Answer: B — Increases rate
Q. What is the effect of light intensity on the rate of photosynthesis?
A.Increases then decreases
B.Decreases
C.Increases
D.No effect
Solution
The rate of photosynthesis generally increases with light intensity up to a certain point.
Correct Answer: C — Increases
Q. What is the end product of anaerobic respiration in plants?
A.Lactic acid
B.Ethanol
C.Carbon dioxide
D.Glucose
Solution
The end product of anaerobic respiration in plants is ethanol, which is produced when oxygen is not available.
Correct Answer: B — Ethanol
Q. What is the end product of the Calvin cycle?
A.Oxygen
B.Glucose
C.NADPH
D.ATP
Solution
The end product of the Calvin cycle is glucose.
Correct Answer: B — Glucose
Q. What is the expected genotype ratio from a cross between two heterozygous individuals (Aa x Aa)?
A.1:1
B.3:1
C.1:2:1
D.9:3:3:1
Solution
The expected genotype ratio from a cross between two heterozygous individuals (Aa x Aa) is 1:2:1, representing the possible combinations of alleles.
Correct Answer: C — 1:2:1
Q. What is the expected genotypic ratio from a dihybrid cross?
A.1:2:1
B.3:1
C.9:3:3:1
D.1:1:1:1
Solution
The expected genotypic ratio from a dihybrid cross is 9:3:3:1, representing the combinations of two traits.
Correct Answer: C — 9:3:3:1
Q. What is the expected genotypic ratio from a monohybrid cross between two heterozygous parents (Aa x Aa)?
A.1:2:1
B.3:1
C.9:3:3:1
D.1:1
Solution
The expected genotypic ratio from a monohybrid cross of Aa x Aa is 1:2:1.
Correct Answer: A — 1:2:1
Q. What is the expected genotypic ratio from a monohybrid cross?
A.1:1
B.3:1
C.1:2:1
D.9:3:3:1
Solution
The expected genotypic ratio from a monohybrid cross is 1:2:1, representing the combinations of alleles.
Correct Answer: C — 1:2:1
Q. What is the expected genotypic ratio in the F2 generation of a monohybrid cross?
A.1:2:1
B.3:1
C.9:3:3:1
D.1:1
Solution
The expected genotypic ratio in the F2 generation of a monohybrid cross is 1:2:1, representing the homozygous dominant, heterozygous, and homozygous recessive genotypes.
Correct Answer: A — 1:2:1
Q. What is the expected genotypic ratio of a dihybrid cross?
A.1:1
B.3:1
C.9:3:3:1
D.1:2:1
Solution
The expected genotypic ratio of a dihybrid cross is 9:3:3:1, representing the combinations of two traits.
Correct Answer: C — 9:3:3:1
Q. What is the expected genotypic ratio of a monohybrid cross?
A.1:1
B.3:1
C.1:2:1
D.9:3:3:1
Solution
The expected genotypic ratio of a monohybrid cross is 1:2:1, representing the combinations of alleles.
Correct Answer: C — 1:2:1
Q. What is the expected phenotypic ratio in a monohybrid cross?
A.3:1
B.1:2:1
C.9:3:3:1
D.1:1
Solution
The expected phenotypic ratio in a monohybrid cross is 3:1 for dominant to recessive traits.
Correct Answer: A — 3:1
Q. What is the expected phenotypic ratio in the F2 generation of a monohybrid cross?
A.3:1
B.1:2:1
C.9:3:3:1
D.1:1
Solution
In a monohybrid cross, the expected phenotypic ratio in the F2 generation is 3:1, where three offspring display the dominant trait and one displays the recessive trait.
Correct Answer: A — 3:1
Q. What is the expected phenotypic ratio in the offspring of a monohybrid cross?
A.1:1
B.3:1
C.9:3:3:1
D.1:2:1
Solution
In a monohybrid cross, the expected phenotypic ratio is 3:1, where three offspring display the dominant trait and one displays the recessive trait.
Correct Answer: B — 3:1
Q. What is the expected phenotypic ratio of a dihybrid cross between two heterozygous individuals (AaBb x AaBb)?
A.3:1
B.9:3:3:1
C.1:2:1
D.1:1
Solution
The expected phenotypic ratio for a dihybrid cross is 9:3:3:1, representing the combinations of two traits.
Correct Answer: B — 9:3:3:1
Q. What is the expected phenotypic ratio of a test cross involving a heterozygous individual?
A.1:1
B.3:1
C.9:3:3:1
D.1:2:1
Solution
The expected phenotypic ratio of a test cross involving a heterozygous individual is 1:1, as it is crossed with a homozygous recessive individual.
Correct Answer: A — 1:1
Q. What is the function of a promoter in gene expression?
A.To enhance transcription
B.To initiate transcription
C.To terminate transcription
D.To bind ribosomes
Solution
A promoter is a DNA sequence that initiates transcription by providing a binding site for RNA polymerase.
Correct Answer: B — To initiate transcription
Q. What is the function of capillaries in the circulatory system?
A.To transport blood to the heart
B.To exchange nutrients and waste
C.To store blood
D.To regulate blood pressure
Solution
Capillaries are small blood vessels that facilitate the exchange of nutrients and waste between blood and tissues.
Correct Answer: B — To exchange nutrients and waste
Q. What is the function of collenchyma cells in plants?
A.Storage of starch
B.Transport of nutrients
C.Providing flexible support
D.Photosynthesis
Solution
Collenchyma cells provide flexible support to young stems and leaves, allowing for growth and movement.
Correct Answer: C — Providing flexible support
Q. What is the function of collenchyma cells?
A.Transport water
B.Provide flexible support
C.Store nutrients
D.Conduct photosynthesis
Solution
Collenchyma cells provide flexible support to young stems and leaves.
Correct Answer: B — Provide flexible support
Q. What is the function of guard cells in plant leaves?
A.Photosynthesis
B.Water storage
C.Regulating gas exchange
D.Nutrient transport
Solution
Guard cells regulate the opening and closing of stomata, controlling gas exchange and water loss.
Correct Answer: C — Regulating gas exchange
Q. What is the function of memory B cells?
A.To produce antibodies immediately
B.To remember past infections
C.To activate T cells
D.To phagocytize pathogens
Solution
Memory B cells are responsible for remembering past infections and can quickly produce antibodies upon re-exposure to the same pathogen.
Correct Answer: B — To remember past infections
Q. What is the function of memory cells in the immune system?
A.To produce immediate immune responses
B.To remember past infections and respond quickly upon re-exposure
C.To activate macrophages
D.To secrete cytokines
Solution
Memory cells are long-lived cells that remember past infections and enable a faster and more effective response upon re-exposure to the same pathogen.
Correct Answer: B — To remember past infections and respond quickly upon re-exposure
Q. What is the function of memory T cells?
A.Immediate response to pathogens
B.Long-term immunity
C.Production of antibodies
D.Activation of macrophages
Solution
Memory T cells provide long-term immunity by remaining in the body after an infection and responding more rapidly upon re-exposure to the same pathogen.
Correct Answer: B — Long-term immunity
Q. What is the function of messenger RNA (mRNA)?
A.To carry amino acids
B.To store genetic information
C.To transfer genetic information from DNA to ribosomes
D.To catalyze biochemical reactions
Solution
Messenger RNA (mRNA) serves as the template that carries genetic information from DNA to ribosomes for protein synthesis.
Correct Answer: C — To transfer genetic information from DNA to ribosomes
