Practice Post UTME UNIOSUN biology 2023 Past Questions

Question 1

In a population of 1000 individuals, 60% are heterozygous for the gene controlling the production of the enzyme lactase. If 20% of the population is homozygous recessive for this gene, what is the frequency of the recessive allele?

Correct A. 0.15

B. 0.20

C. 0.25

D. 0.30

Correct Answer: A

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

Question 2

A diagram of a plant cell is shown below. What is the function of the structure labeled A?

A. to produce energy for the cell

B. to synthesize proteins

Correct C. to store genetic information

D. to regulate cell growth

Correct Answer: C

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

Question 3

In a random sample of 1000 individuals, 70% have a certain genetic disorder. If 20% of the population is homozygous recessive for the gene controlling this disorder, what is the frequency of the recessive allele?

A. 0.15

Correct B. 0.20

C. 0.25

D. 0.30

Correct Answer: B

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

Question 4

A diagram of a simple e\cosystem is shown below. What is the role of the structure labeled B?

A. to produce energy for the e\cosystem

Correct B. to synthesize nutrients

C. to regulate water flow

D. to maintain soil quality

Correct Answer: B

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

Question 5

In a population of 1000 individuals, 60% are heterozygous for the gene controlling the production of the enzyme lactase. If 20% of the population is homozygous recessive for this gene, what is the frequency of the dominant allele?

A. 0.40

B. 0.45

Correct C. 0.50

D. 0.55

Correct Answer: C

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

Question 6

A study on the genetic variation of a population found that the frequency of the recessive allele is 0.2. If the population is in Hardy-Weinberg equilibrium, what is the frequency of the dominant allele?

Correct A. 0.8

B. 0.6

C. 0.4

D. 0.2

Correct Answer: A

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

Question 7

In a plant, the xylem tissue is responsible for transporting water and minerals from the roots to the leaves. Which of the following structures is NOT a part of the xylem tissue?

A. Tracheid

B. Xylem vessel

C. Phloem

Correct D. Parenchyma cell

Correct Answer: D

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

Question 8

The process of cellular respiration involves the breakdown of glu\cose to produce energy in the form of ATP. Which of the following stages of cellular respiration is responsible for the production of ATP?

A. Glycolysis

B. Pyruvate oxidation

C. Citric acid cycle

Correct D. Electron transport chain

Correct Answer: D

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

Question 9

A microorganism is isolated from a patient's blood sample and identified as Staphylococcus aureus. Which of the following characteristics is a common feature of this microorganism?

Correct A. Gram-positive

B. Gram-negative

C. Spore-forming

D. Motile

Correct Answer: A

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

Question 10

The theory of evolution by natural selection was first proposed by Charles Darwin in his book 'On the Origin of Species'. Which of the following is a key concept of this theory?

Correct A. Survival of the fittest

B. Speciation

C. Adaptation

D. Genetic drift

Correct Answer: A

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

Question 11

In the process of osmoregulation, what is the primary function of the kidneys in a hypertonic environment?

A. To dilute the blood to match the surrounding environment

Correct B. To concentrate the urine to conserve water

C. To excrete excess ions to maintain electrolyte balance

D. To regulate blood pressure through vasoconstriction

Correct Answer: B

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

Question 12

What is the primary mechanism by which the respiratory system regulates pH levels in the blood?

A. Through the buffering capacity of hemoglobin

B. Through the excretion of excess hydrogen ions in the urine

Correct C. Through the exchange of CO2 and O2 in the lungs

D. Through the regulation of breathing rate

Correct Answer: C

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

Question 13

In the context of hormonal coordination, what is the primary function of the hypothalamus?

A. To regulate body temperature

B. To control appetite and satiety

Correct C. To stimulate the release of hormones from the pituitary gland

D. To regulate sleep-wake cycles

Correct Answer: C

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

Question 14

What is the primary mechanism by which the reproductive system regulates the timing of gamete release?

Correct A. Through the regulation of hormone levels

B. Through the control of breathing rate

C. Through the exchange of CO2 and O2 in the lungs

D. Through the regulation of body temperature

Correct Answer: A

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

Question 15

In the context of tissue structure, what is the primary function of the basement membrane?

A. To provide structural support to the tissue

Correct B. To regulate the exchange of nutrients and waste products

C. To facilitate the movement of cells through the tissue

D. To regulate the immune response

Correct Answer: B

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

Question 16

What is the primary mechanism by which the nervous system regulates muscle contraction?

Correct A. Through the release of neurotransmitters

B. Through the regulation of hormone levels

C. Through the exchange of CO2 and O2 in the lungs

D. Through the regulation of body temperature

Correct Answer: A

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

Question 17

In the context of organ systems, what is the primary function of the integumentary system?

A. To regulate body temperature

Correct B. To protect the body from external damage

C. To facilitate the exchange of nutrients and waste products

D. To regulate the immune response

Correct Answer: B

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

Question 18

What is the primary mechanism by which the circulatory system regulates blood pressure?

A. Through the regulation of heart rate

B. Through the control of breathing rate

C. Through the exchange of CO2 and O2 in the lungs

Correct D. Through the regulation of blood vessel diameter

Correct Answer: D

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

Question 19

In the context of tissue structure, what is the primary function of the extracellular matrix?

Correct A. To provide structural support to the tissue

B. To regulate the exchange of nutrients and waste products

C. To facilitate the movement of cells through the tissue

D. To regulate the immune response

Correct Answer: A

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

Question 20

What is the primary mechanism by which the nervous system regulates the timing of sleep-wake cycles?

A. Through the regulation of hormone levels

B. Through the control of breathing rate

C. Through the exchange of CO2 and O2 in the lungs

D. Through the regulation of body temperature

Correct Answer: VIEW ANSWER

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

Question 21

In a tropical rainforest, the presence of a large number of epiphytes is an example of a(n) _______________ relationship between the epiphytes and their host plants.

Correct A. mutualistic

B. commensalistic

C. parasitic

D. symbiotic

Correct Answer: A

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

Question 22

The process by which plants release water vapor into the air through their leaves is called _______________.

Correct A. transpiration

B. respiration

C. photosynthesis

D. evaporation

Correct Answer: A

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

Question 23

The structure of the human eye that allows it to focus on objects at different dis\tances is the _______________.

A. cornea

B. iris

Correct C. lens

D. retina

Correct Answer: C

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

Question 24

The process by which cells divide to produce two daughter cells is called _______________.

Correct A. mitosis

B. meiosis

C. binary fission

D. \endosymbiosis

Correct Answer: A

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

Question 25

The hormone that regulates the level of glu\cose in the blood is _______________.

Correct A. insulin

B. glucagon

C. adrenaline

D. thyroxine

Correct Answer: A

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

POST UTME UNIOSUN 2023 Biology | Objective

Master the Exam!

Help others prepare! Share this practice hub: