Practice post utme aaua biology 2025 Past Questions

Question 1

A population of Drosophila melanogaster is being studied for its genetic variation. The frequency of the recessive allele 'a' is 0.2, and the frequency of the dominant allele 'A' is 0.8. What is the expected frequency of the homozygous recessive genotype 'aa'?

Correct A. 0.16

B. 0.24

C. 0.32

D. 0.40

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 2

A diagram of a plant's xylem and phloem is shown below. What is the primary function of the xylem?

Correct A. Transporting water and minerals from the roots to the leaves

B. Transporting sugars and other organic compounds from the leaves to the rest of the plant

C. Supporting the plant's structure

D. Regulating the plant's temperature

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 3

A diagram of a human digestive system is shown below. What is the primary function of the small intestine?

Correct A. Breaking down proteins and fats into smaller molecules

B. Absorbing water and electrolytes

C. Storing waste until it can be eliminated

D. Producing digestive enzymes

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 4

A diagram of a plant's photosynthetic pathway is shown below. What is the primary function of the light-dep\endent reactions?

Correct A. Converting light energy into chemical energy

B. Converting chemical energy into light energy

C. Regulating the plant's temperature

D. Supporting the plant's structure

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 5

A diagram of a human eye is shown below. What is the primary function of the lens?

Correct A. Focu\sing light onto the retina

B. Regulating the amount of light entering the eye

C. Supporting the eye's structure

D. Producing tears

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 6

A study on the genetic basis of antibiotic resis\tance in bacteria revealed that the resis\tance gene is located on a plasmid. Which of the following best describes the relationship between the plasmid and the bacterial chromosome?

Correct A. The plasmid is a circular DNA molecule that replicates indep\endently of the bacterial chromosome.

B. The plasmid is a linear DNA molecule that is integrated into the bacterial chromosome.

C. The plasmid is a small DNA molecule that is attached to the bacterial chromosome.

D. The plasmid is a viral genome that infects the bacterial cell.

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 7

A researcher is studying the effect of pH on the growth of E. coli. The researcher measures the growth of the bacteria at different pH levels and plots the data on a graph. Which of the following best describes the relationship between pH and bacterial growth?

A. The growth of E. coli increases as the pH increases.

Correct B. The growth of E. coli decreases as the pH decreases.

C. The growth of E. coli is unaffected by changes in pH.

D. The growth of E. coli is optimal at a pH of 7.

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 8

A geneticist is studying the inheri\tance of a trait in a population of mice. The geneticist observes that the trait is inherited in an autosomal dominant pattern. Which of the following best describes the probability of a mouse inheriting the dominant allele?

Correct A. 50%

B. 25%

C. 75%

D. 100%

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 9

A bio\logist is studying the structure of a cell membrane. The bio\logist observes that the cell membrane is composed of a phospholipid bilayer with embedded proteins. Which of the following best describes the function of the embedded proteins?

Correct A. To regulate the movement of molecules across the cell membrane.

B. To provide structural support to the cell membrane.

C. To facilitate the transmission of signals across the cell membrane.

D. To synthesize proteins within the cell.

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 10

A population eco\logist is studying the dynamics of a predator-prey system. The eco\logist observes that the population of the predator species is increa\sing while the population of the prey species is decrea\sing. Which of the following best describes the relationship between the predator and prey species?

Correct A. The predator species is preying on the prey species.

B. The prey species is competing with the predator species for resources.

C. The predator species is providing a source of food for the prey species.

D. The predator species is a parasite of the prey species.

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 11

In the context of xylem transport, what is the primary function of the xylem parenchyma cells?

Correct A. Storage of water and nutrients

B. Transport of water and minerals

C. Production of ethylene

D. Regulation of stomatal aperture

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 12

According to the Hardy-Weinberg principle, what is the expected frequency of the homozygous recessive genotype in a population?

A. 0.25

Correct B. 0.5

C. 0.75

D. 1.0

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 13

In the context of cell division, what is the primary function of the centrioles?

Correct A. Formation of the spindle fibers

B. Production of the mitotic spindle

C. Regulation of the cell cycle

D. Storage of genetic material

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 14

According to the theory of natural selection, what is the primary mechanism by which populations adapt to their environment?

A. Genetic drift

B. Gene flow

C. Mutation

Correct D. Differential reproduction

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 15

In the context of excretion, what is the primary function of the kidneys?

A. Regulation of blood pressure

Correct B. Production of urine

C. Storage of waste products

D. Regulation of electrolyte balance

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 16

In a population of Drosophila melanogaster, the frequency of the recessive allele 'a' is 0.2. If the population is in Hardy-Weinberg equilibrium, what is the frequency of the homozygous dominant genotype 'AA'?

Correct A. 0.36

B. 0.64

C. 0.72

D. 0.84

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 17

A plant with the genotype 'Rr' is crossed with a plant with the genotype 'RR'. What is the probability that the offspring will have the genotype 'Rr'?

A. 0.25

Correct B. 0.5

C. 0.75

D. 0.9

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 18

In a human population, the frequency of the 'B' allele is 0.4. If the population is in Hardy-Weinberg equilibrium, what is the frequency of the homozygous recessive genotype 'bb'?

Correct A. 0.16

B. 0.36

C. 0.64

D. 0.84

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 19

A plant with the genotype 'Rr' is crossed with a plant with the genotype 'rr'. What is the probability that the offspring will have the genotype 'Rr'?

Correct A. 0.5

B. 0.75

C. 0.9

D. 0.95

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 20

In a population of Drosophila melanogaster, the frequency of the recessive allele 'a' is 0.2. If the population is in Hardy-Weinberg equilibrium, what is the frequency of the homozygous dominant genotype 'AA'?

Correct A. 0.36

B. 0.64

C. 0.72

D. 0.84

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 21

In a population of Drosophila melanogaster, the frequency of the recessive allele 'a' is 0.2. If the population is in Hardy-Weinberg equilibrium, what is the frequency of the homozygous dominant genotype 'AA'?

A. 0.36

Correct B. 0.64

C. 0.8

D. 0.16

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 22

A plant with the genotype 'Rr' is crossed with a plant with the genotype 'RR'. What is the probability that the offspring will have the genotype 'Rr'?

A. 0.25

Correct B. 0.5

C. 0.75

D. 0.9

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 23

A cell is in the G2 phase of the cell cycle. What is the next phase of the cell cycle?

A. G1

B. S

C. G2

Correct D. M

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 24

A population of bacteria is growing exponentially. If the initial population is 100 and the population doubles every 2 hours, what is the population after 6 hours?

A. 1600

B. 3200

Correct C. 6400

D. 12800

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 25

A plant with the genotype 'Tt' is crossed with a plant with the genotype 'tt'. What is the probability that the offspring will have the genotype 'TT'?

Correct A. 0.25

B. 0.5

C. 0.75

D. 0.9

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

POST UTME AAUA 2025 Biology | Objective

Master the Exam!

Help others prepare! Share this practice hub: