All Free Biology MCQs with Answers

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19844 questions · page 572 of 1985

5711. In vivo method of treatment is being tried in:

Moderate
  • A. SCIDS
  • B. Cystic fibrosis
  • C. Hypercholesterolemia
  • D. Familial hypercholesterolemia

Explanation: The gene is introduced into the nasal sinus by coating it on liposomes which are sprayed just like inhalers in the nasal sinuses.

Correct answer: Cystic fibrosis

5712. The in-vivo method of treatment of cystic fibrosis by gene coated liposomes, has not yet been successful due to:

Moderate
  • A. Non gene transfer
  • B. Limited gene transfer
  • C. Excessive gene transfer
  • D. High cost

Explanation: Due to limited gene transfer, this methodology has not yet been successful.

Correct answer: Limited gene transfer

5713. Nucleotides sequence that is identical to its complementary strand when each is read in the same chemical direction for example GATC i-e; 5  GATC ... 3 3 ... CATG ... 5 these are called as:

Moderate
  • A. Flanking sequences
  • B. Nucleotide order
  • C. Palindromic sequences
  • D. Antagonistic sequences

Explanation: The definition and example have are given on glossary at page VIII of textbook of biology part-II.

Correct answer: Palindromic sequences

5714. An enzyme that cleaves a DNA duplex molecule, at a particular base sequence, usually within or near a palindromic sequence, is called:

Moderate
  • A. Polymerase
  • B. Helicase
  • C. Restriction endonuclease
  • D. Ligase

Explanation: The definition is on glossary page IX of textbook of biology part II.

Correct answer: Restriction endonuclease

5715. Which one of the following technique rapidly replicates specific target fragment of DNA without cloning?

Moderate
  • A. DNA sequencing
  • B. Genetic probe
  • C. Gel electrophoresis
  • D. Polymerase chain reaction

Explanation: PCR involves using short synthetic DNA fragments called primers to select a segment of the genome to be amplified, and then multiple rounds of DNA synthesis to amplify that segment.

Correct answer: Polymerase chain reaction

5716. Genes of interest can be selected from a genomic library by using:

Moderate
  • A. Cloning vectors
  • B. DNA probes
  • C. Gene targets
  • D. Restriction enzymes

Explanation: A gene bank or genomic library is a complete collection of cloned DNA fragments that comprises the entire genome of an organism. Molecular probes are small DNA segments that are used to detect the presence of complementary sequences in nucleic acid samples in the genomic library. These are usually formed of 200­500 nucleotide sequences. These segments or probes are labeled either with radioactive or nonradioactive compounds. Probes with DNA sequences complementary to the gene to be isolated are used. They bind with the desired gene, making it visible and help in isolating it from the library.

Correct answer: DNA probes

5717. The deficiency of which of the following cause immunodeficiency?

Moderate
  • A. Hypoxanthine-guanine transferase
  • B. Xanthine oxidase
  • C. PRPP synthetase
  • D. Adenosine deaminase

Explanation: The deficiency of Adenosine deaminase (ADA) causes immunodeficiency. ADA is an enzyme that is responsible for breaking down adenosine, a type of nucleic acid. When ADA is deficient, adenosine builds up in the body, which can damage the immune system. This can lead to a variety of immunodeficiency disorders, including severe combined immunodeficiency (SCID).

Correct answer: Adenosine deaminase

5718. Each sentence below has a blank indicating that something has been omitted. Choose the word that best fits in with the meaning of the sentence as a whole.Even though the physical structure of the college's lunchroom appears dilapidated in many regards, it was extended and_ quite lately.

Moderate
  • A. Stayed
  • B. Inspected
  • C. Conquered
  • D. Renovated

Explanation: The word "Even though" at the beginning of the sentence is an opposition indicator. As a contrast to the dilapidated condition of the school, the word "renovated" is the acceptable choice.

Correct answer: Renovated

5719. Not only, the students but also, their instructor --- been called to the principal's office.

Moderate
  • A. has
  • B. have
  • C. were
  • D. was

Explanation: The correct answer is has because the construction 'Not only...but also' typically treats the closest subject as the primary subject for verb agreement. In this case, 'instructor' is singular, thus requiring the singular verb 'has'. The options 'have' and 'were' are incorrect because they are plural verbs that do not correspond with the singular subject. Although 'was' is singular, it does not fit the context of the sentence as well as 'has', which implies a more immediate action in this scenario.

Correct answer: has

5720. In this section of logical deduction, the question consists of a brief passage (usually a report containing certain data regarding some social or economic problem), followed by certain inferences based on it. The student is required to analyze the contents (or data) of the passage and grasp the desirable facts from it. Then, student has to consider each of the given inferences in the context of the given passage. decide upon its degree of truth or falsity and then choose the hest alternative provided accordingly.Primary education in Sindh is in a poor shape. Pupils in over 50 percent of the schools read in the open throughout the year. Over six million children born to lower Income group parents remain unlettered. Not even one percent of the 63,000 primary schools have facilities of furniture, toilet, drinking water and games. 3 113 new teachers have been appointed in the current financial year out of which 2747 are women. Now each of the 13,270 primary schools have at least two teachers.630 primary schools in Sindh have all the facilities like furniture, toilet, drinking water, games.

Moderate
  • A. Definitely true
  • B. Probably true
  • C. Data inadequate
  • D. Probably false
  • E. Definitely false

Explanation: The statement '630 primary schools in Sindh have all the facilities like furniture, toilet, drinking water, games' is definitely false. The passage states that less than one percent of 63,000 schools are equipped with these facilities, which translates to significantly fewer than 630 schools. Therefore, the statement directly contradicts the passage. The options suggesting it could be true or that data is inadequate are incorrect since the passage provides clear and sufficient data to reach a definitive conclusion.

Correct answer: Definitely false