POST UTME OAU 2023 Biology | Objective

Are you preparing for POST UTME OAU exams? Reviewing past questions is one of the most effective ways to guarantee a high score. This practice hub features authentic 2023 Biology (Objective) questions designed to simulate the real exam environment.

Practice these randomly selected questions to test your readiness.

Question 1
In a desert e\cosystem, what is the primary mechanism by which plants regulate water loss through their leaves?
Correct A. Transpiration
B. Respiration
C. Photosynthesis
D. Osmosis

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 2
A 2-year-old boy is unable to hear his mother's voice when she speaks in a normal tone. However, he can hear her voice when she speaks loudly. What is the most likely cause of this condition?
A. Otosclerosis
B. Meniere's disease
C. Conductive hearing loss
Correct D. Sensorineural hearing loss

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 3
A diagram of a human eye is shown below. What is the function of the part labeled 'A'?
Correct A. To focus light on the retina
B. To detect light intensity
C. To regulate pupil size
D. To produce tears

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 4
A diagram of a plant's xylem is shown below. What is the primary function of the part labeled 'B'?
Correct A. To transport water and minerals from the roots to the leaves
B. To transport sugars and other organic compounds from the leaves to the rest of the plant
C. To store water and nutrients
D. To regulate gas exchange

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 5
A diagram of a human reproductive system is shown below. What is the primary function of the part labeled 'C'?
A. To produce sperm
Correct B. To produce eggs
C. To store sperm
D. To regulate hormone production

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 6
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 7
A 2.5-metre-tall tree is observed to cast a shadow of 1.8 metres. At the same time, a nearby building casts a shadow of 4.2 metres. What is the height of the building?
A. 6.0
Correct B. 8.1
C. 10.5
D. 12.6

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 8
A 0.5-mole sample of carbon dioxide gas is collected over water at 25°C and 1 atm. If the partial pressure of water vapor is 23.8 torr, what is the mole \fraction of carbon dioxide?
A. 0.97
B. 0.98
C. 0.99
Correct D. 0.995

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 9
A 50-g sample of a mixture of sodium chloride and sodium sulfate is dissolved in 100 mL of water. If the resulting solution has a pH of 7.5, what is the concentration of chloride ions?
A. 0.15 M
Correct B. 0.20 M
C. 0.25 M
D. 0.30 M

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 10
A population of 1000 individuals has a mean height of 170 cm and a s\tandard deviation of 10 cm. If a random sample of 50 individuals is taken, what is the probability that the sample mean is greater than 175 cm?
Correct A. 0.05
B. 0.10
C. 0.15
D. 0.20

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 11
In a population of 1000 bacteria, 80% are resis\tant to antibiotic A. If 200 bacteria are randomly selected for treatment, what is the probability that at least 150 will be resis\tant to antibiotic A?
Correct A. 0.95
B. 0.80
C. 0.60
D. 0.40

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 12
A 2.0 L flask contains 0.50 M NaCl. If 0.20 M CaCl2 is added to the flask, what is the new concentration of NaCl?
A. 0.30 M
Correct B. 0.40 M
C. 0.50 M
D. 0.60 M

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 13
A plant with a height of 10 cm has a root system that ext\ends 5 cm below the soil surface. If the plant is subjected to a drought, how far will the root system ext\end below the soil surface?
A. 2 cm
B. 5 cm
Correct C. 10 cm
D. 15 cm

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 14
A 50 kg person is running at a speed of 5 m/s. If the person is subjected to a force of 100 N, what is the acceleration of the person?
A. 0.5 m/s^2
B. 1.0 m/s^2
Correct C. 2.0 m/s^2
D. 5.0 m/s^2

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 15
A population of 1000 bacteria is growing at a rate of 20% per hour. If the population is 500 after 2 hours, what is the growth rate per hour?
A. 10%
B. 15%
Correct C. 20%
D. 25%

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 16
The process of genetic drift in a population can lead to the loss of genetic variation over time. Which of the following is a consequence of genetic drift?
A. Increased genetic variation
Correct B. Decreased genetic variation
C. No change in genetic variation
D. Increased mutation rate

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 17
A diagram of the xylem and phloem tissues in a plant stem is shown below. What is the function of the xylem tissue?
Correct A. Transport of water and minerals
B. Transport of sugars and amino acids
C. Support and storage
D. Protection from pathogens

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 18
The Hardy-Weinberg principle states that the frequency of alleles in a population will remain cons\tant from generation to generation in the absence of certain factors. Which of the following is NOT one of the factors that can cause a change in allele frequency?
A. Mutation
B. Gene flow
C. Genetic drift
Correct D. Natural selection

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 19
A diagram of the cell cycle is shown below. What is the function of the G1 phase?
A. DNA replication
Correct B. Cell growth and preparation for division
C. Mitosis
D. Cytokinesis

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 20
The concept of natural selection was first proposed by Charles Darwin in his book 'On the Origin of Species'. Which of the following is a key component of natural selection?
Correct A. Genetic variation
B. Mutation
C. Gene flow
D. Genetic drift

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 21
In a eukaryotic cell undergoing mitosis, which of the following structures is responsible for the separation of chromosomes during anaphase?
A. Centrioles
Correct B. Spindle fibers
C. Cytokinesis
D. Telophase

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 22
A population of rabbits is growing at a rate of 20% per year. If the initial population is 100 rabbits, what will be the population after 5 years?
A. 1000
B. 1600
C. 2000
Correct D. 2500

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 23
In a sexual reproduction process, what is the term for the fusion of male and female gametes to form a zygote?
A. Meiosis
B. Mitosis
C. Fertilization
Correct D. Syngamy

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 24
A researcher is studying the effect of pH on the growth of a microorganism. The researcher notices that the microorganism grows best at a pH of 7. If the pH of the medium is increased to 9, what will happen to the growth of the microorganism?
A. The growth will increase
Correct B. The growth will decrease
C. The growth will remain the same
D. The growth will stop

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 25
In a e\cosystem, what is the term for the process by which plants convert light energy from the sun into chemical energy in the form of glu\cose?
A. Respiration
Correct B. Photosynthesis
C. Decomposition
D. Fermentation

Correct Answer: B

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

Master the Exam!

You've seen a preview, but there are thousands more questions plus AI tutor to break down complex solutions.

Unlock Full Access Available for Android & Windows
Help others prepare! Share this practice hub:
Chat with Support