All Free Biology MCQs with Answers
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19844 questions · page 573 of 1985
5721. Directions: In the following question, a number sequence is given with one term missing. Choose the correct term that will continue the same pattern and replace the question mark in the given sequence.1,2,4,7,?,16
- A. 8
- B. 11
- C. 9
- D. 13
Explanation: To solve the sequence 1, 2, 4, 7, ?, 16, observe the differences between consecutive terms: +1, +2, +3. The pattern indicates that the differences are increasing sequentially by 1. Thus, the next difference should be +4. Adding 4 to 7 results in 11, completing the sequence as 1, 2, 4, 7, 11, 16. Therefore, the correct answer is 11. The other options 8, 9, and 13 do not follow this established pattern, making them incorrect choices.
Correct answer: 115722. Directions: Read the following information and give answer.In a cricket season, Pakistan -defeated Australia twice, West Indies defeated Pakistan twice, Australia defeated West Indies twice, Pakistan defeated New Zealand twice, and West Indies defeated New Zealand twice.Which country has lost the greatest number of times?
- A. Pakistan
- B. Australia
- C. New Zealand
- D. West Indies
Explanation: To determine which country has lost the greatest number of times, we need to analyze the match outcomes:Pakistan defeated Australia twice, leading to 2 losses for Australia.West Indies defeated Pakistan twice, resulting in 2 losses for Pakistan.Australia defeated West Indies twice, giving 2 losses to West Indies.Pakistan defeated New Zealand twice, contributing 2 losses to New Zealand.West Indies defeated New Zealand twice, adding another 2 losses to New Zealand.Now, let's total the losses for each country:Australia: 2 losses (to Pakistan)Pakistan: 2 losses (to West Indies)West Indies: 2 losses (to Australia)New Zealand: 4 losses (2 to Pakistan, 2 to West Indies)Thus, New Zealand has lost the greatest number of times with 4 losses. The other countries each have 2 losses, which is less than New Zealand's total.
Correct answer: New Zealand5723. In the following question, two statements numbered I and II are given. There may be cause and effect relationship between the two statements. These two statements may be the effect of the same cause or independent causes. These statements may be independent causes without saving any relationship. Read both the statements in question and mark your answer as:A. If statement I is the cause and statement II is its effect;B. If statement II is the cause and statement, I is its effect;C. If both the statements I and II are independent causes;D. If both the statements I and II are effects of independent causes;E. If both the statements I and II are effects of some common causes;I. All the schools in the area had to be kept closed for most part of the week.II. Many parents have withdrawn their childrenN from the local schools.
- A. If statement I is the cause and statement II its effect;
- B. If statement II is the cause and statement, I is its effect;
- C. If both the statements I and II areindependent causes;
- D. If both the statements I and II are effects of independent causes;
- E. If both the statements I and II are effects of some common cause;
Explanation: Keeping school closed and withdrawing students from school by parents seems to be effect of relating causes. Something might have happened which can lead to pertaining of such a effect. Thus, Both are related.
Correct answer: If both the statements I and II are effects of some common cause;5724. In this question, a statement is given followed by two courses of action numbered I and II. It is required to grasp the statement, analyze the problem or policy it mentions and then decide which of the courses of action logically follow / most appropriate.Statement:Floods may create havoc in the country this year too.Courses of action:I) The Government should be on the alert to evacuate flood-affected victims.II) People should not be afraid of floods.
- A. If only I follows
- B. If only II follows
- C. If either I or II follows
- D. If neither I nor II follows
- E. If both I and II follow
Explanation: The statement warns of potential havoc from floods, suggesting an urgent need for preparedness. Course of action I logically follows as it proposes a practical government response to evacuate affected individuals, directly addressing the potential crisis. Course of action II, by advising people not to be afraid, fails to provide a tangible or helpful response to the threat posed by floods, making it an inappropriate course of action. Therefore, the correct answer is that only course of action I follows.
Correct answer: If only I follows5725. The given diagram shows different types of blood vessels involved in the blood circulation in the human body.The blood vessel with the LOWEST rate of blood flow is:
- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: Each capillary is extremely narrow, there are millions of them, and this wide distribution forces the blood to spread out, slowing it down.Blood flow rate is lowest in capillariesso option D is correct.
Correct answer: Option D5726. Following are the characteristics of a blood disorder.I.Reduced levels of haemoglobin.II.Low RBCs production.The blood disorder identified is:
- A. Oedema
- B. Leukaemia
- C. Thalassemia
- D. Atherosclerosis
Explanation: Thalassemia is a genetic disorder that affects the body's ability to produce normal haemoglobin, leading to reduced levels of haemoglobin and low production of red blood cells (RBCs).The key symptoms mentioned in the question 'Reduced levels of haemoglobin' and 'Low RBCs production' directly point to thalassemia.
Correct answer: Thalassemia5727. The given diagram shows a method used by Alina to measure the blood pressure of herclassmate. She heard a sound during phase II and noted the blood pressure as 120/80 mmHg (millimetres of mercury).She infers that the sound was audible during phase II because the
- A. Blood flow in the brachial artery becomes turbulent, creating audible sounds
- B. The diameter of the lumen of the brachial artery gets minimized
- C. The pressure in the cuff is greater than the pressure in the artery
- D. Enough air pressure is pumped into the cuff to close the artery
Explanation: During blood pressure measurement, sounds are heard as blood starts to flow through the compressed artery and becomes turbulent. This typically occurs during phase II, known as the Korotkoff sounds, when the cuff's pressure is between the systolic and diastolic pressures. The correct option is that blood flow in the brachial artery becomes turbulent, creating audible sounds. The other options are incorrect as they either describe different phases or do not account for the turbulent flow that causes the sound.
Correct answer: Blood flow in the brachial artery becomes turbulent, creating audible sounds5728. The large arteries close to the heart have a thick elastic layer in their walls to:
- A. Prevent collapse of these blood vessels
- B. Reduce friction within these blood vessels
- C. Anchor these vessels with surrounding tissues
- D. Prevent too much pressure exerted on their walls
Explanation: The thick elastic layer in the walls of large arteries, such as the aorta, is crucial for maintaining blood pressure and ensuring efficient blood flow. This elasticity allows the arteries to stretch and accommodate the surge of blood with each heartbeat, then recoil to help push the blood forward. This action prevents excessive pressure from being exerted on the arterial walls, which could otherwise lead to damage or rupture.
Correct answer: Prevent too much pressure exerted on their walls5729. The rate of blood flow is the slowest in capillaries than other blood vessels because the:
- A. Capillaries lack valves
- B. Capillaries have one cell thick walls
- C. Resistance in blood flow is negligible in capillaries
- D. Total cross-sectional area of the capillaries is greater than other vessels
Explanation: The correct answer is that the rate of blood flow is slowest in capillaries because the total cross-sectional area of the capillaries is greater than other vessels. This increased area reduces the velocity of blood flow, allowing more time for the exchange of oxygen, carbon dioxide, nutrients, and waste products between blood and tissues.
Correct answer: Total cross-sectional area of the capillaries is greater than other vessels5730. The blood pressure of a person 176/105 mm Hg.Which of the following is the BEST interpretation of this reading?
- A. Normal
- B. Hypotension
- C. Mild hypertension
- D. Hypertension requiring treatment
Explanation: The reading of 176/105 mm Hg indicates stage 2 hypertension, which is characterized by a systolic pressure of 160 mm Hg or higher and/or a diastolic pressure of 100 mm Hg or higher. This level of hypertension typically requires medical treatment to manage the risk of cardiovascular complications.
Correct answer: Hypertension requiring treatment