Q711. What happens immediately after Cas9 makes a double-strand break in the target DNA?
Science and Technology: RAS Prelims MCQs
1113 RAS Prelims practice MCQs on science and technology are on this page, in 6 chapters. They cover the basics of everyday science, computers and information technology, defence and space technology in India, genetics, biotechnology and nanotechnology, science and technology policies and government programmes, and recent advances with Indian contributors and indigenisation. Each question has an answer and an explanation.
Practice questions based on the RPSC RAS Prelims syllabus. They follow the exam pattern but are not past-paper questions.
Showing 711–720 of 1113 questions
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Q712. Off-target effects in CRISPR technology refer to:
Explanation
A major challenge in CRISPR technology is the occurrence of off-target effects, which happen when the Cas9 enzyme binds to and cuts DNA at locations other than the intended target. This occurs because the guide RNA may accidentally recognize sequences that are very similar to the target site. These unintended cuts can lead to harmful mutations elsewhere in the genome, raising safety concerns.
Q713. Gene drive is a controversial application of CRISPR that allows:
Explanation
A gene drive is a sophisticated application of CRISPR that ensures a specific genetic modification is passed on to nearly all offspring, bypassing traditional inheritance. This allows the modification to spread rapidly through an entire wild population. While it could be used to eliminate disease-carrying mosquitoes, it raises significant ethical and ecological concerns due to its potential to permanently alter entire ecosystems.
Q714. Stem cells possess two fundamental properties: self-renewal and the ability to differentiate into specialized cell types. Cells that can develop into a complete organism are termed:
Explanation
Totipotent stem cells possess the highest level of differentiation potential. A single totipotent cell, such as a zygote or cells from the very first few divisions, has the extraordinary ability to differentiate into any cell type in the body as well as the extra-embryonic tissues like the placenta. Consequently, these cells have the capacity to develop into a complete, independent organism.
Q715. Consider the following statements regarding stem cells:
Statement I: Adult stem cells are generally multipotent, meaning they can only differentiate into a limited number of cell types related to their tissue of origin.
Statement II: Embryonic stem cells, derived from the inner cell mass of a blastocyst, are pluripotent and can form any cell type in the adult body.
Which of the following represents the correct option?
Statement I: Adult stem cells are generally multipotent, meaning they can only differentiate into a limited number of cell types related to their tissue of origin.
Statement II: Embryonic stem cells, derived from the inner cell mass of a blastocyst, are pluripotent and can form any cell type in the adult body.
Which of the following represents the correct option?
Explanation
Adult stem cells are multipotent, meaning they are typically restricted to becoming cell types within their specific tissue of origin, such as blood stem cells only making blood cells. In contrast, embryonic stem cells are pluripotent; they are derived from the blastocyst and have the broader capability to differentiate into any of the more than 200 specialized cell types in the body.
Q716. Consider the following statements about Induced Pluripotent Stem Cells (iPSCs):
I. They are adult somatic cells genetically reprogrammed to an embryonic stem cell-like state.
II. Their creation bypasses the ethical concerns associated with destroying human embryos.
III. They can only differentiate into blood cells.
Which of the above statement(s) is/are correct?
I. They are adult somatic cells genetically reprogrammed to an embryonic stem cell-like state.
II. Their creation bypasses the ethical concerns associated with destroying human embryos.
III. They can only differentiate into blood cells.
Which of the above statement(s) is/are correct?
Explanation
Induced Pluripotent Stem Cells are created by genetically reprogramming specialized adult cells, like skin cells, back into an embryonic-like state. This breakthrough allows for the creation of pluripotent cells without using or destroying embryos, thus avoiding major ethical controversies. However, iPSCs are pluripotent and can potentially differentiate into almost any cell type in the body, which makes certain specialized restrictions incorrect.
Q717. The generation of tissues or organs from stem cells to replace damaged ones is the primary goal of:
Explanation
Regenerative medicine is a specialized field of medicine focused on repairing, replacing, or regenerating human cells, tissues, or organs to restore normal function. This often involves using stem cells to create new, healthy tissue that can be transplanted into patients to replace parts damaged by disease, injury, or aging. Examples include growing skin for burn victims or potentially regenerating heart muscle.
Q718. Which of the following represents an ethical concern exclusively associated with human embryonic stem cell research?
Explanation
The most prominent and unique ethical challenge associated with human embryonic stem cell research is that the process of isolating these cells currently necessitates the destruction of a five-day-old human embryo. This raises profound moral and religious questions for many people regarding the status of the embryo and the ethics of destroying potential human life, a concern not shared with adult stem cells.
Q719. Identify the correct pair regarding stem cell types:
Explanation
The inner cell mass of a blastocyst contains pluripotent stem cells, which can become any cell type in the body. A zygote is actually totipotent, not multipotent. Mesenchymal stem cells are multipotent, as they can form bone, cartilage, and fat, but not a whole organism. Skin stem cells are also multipotent, restricted to regenerating skin-related tissues in various biological organisms.
Q720. Which scientist was awarded the Nobel Prize in 2012 for the discovery that mature cells can be reprogrammed to become pluripotent (iPSCs)?
Explanation
Shinya Yamanaka was awarded the Nobel Prize in Physiology or Medicine in 2012 for his groundbreaking discovery that mature, specialized cells can be reprogrammed to become pluripotent stem cells. By introducing four specific genes into adult skin cells, he showed it was possible to turn back the developmental clock, creating cells nearly identical to embryonic stem cells. This technology has revolutionized medicine.Answer key for these questions
| Q | Correct answer |
|---|---|
| 711 | (a) The cell’s natural DNA repair mechanisms try to fix the break. |
| 712 | (c) Cas9 cutting DNA at unintended sites with similar sequences |
| 713 | (d) Promoting universal inheritance of a genetic alteration |
| 714 | (b) Totipotent |
| 715 | (a) Both Statement I and Statement II are correct. |
| 716 | (a) I and II only |
| 717 | (b) Regenerative medicine |
| 718 | (a) It requires the destruction of early-stage human embryos. |
| 719 | (c) Inner cell mass of blastocyst - Pluripotent |
| 720 | (b) Shinya Yamanaka |
Key facts from Science and Technology
- The RPSC paper is General Knowledge and General Science, so science questions come with a strong dose of applied and recent topics.
- Everyday science questions test the laws and terms of physics, chemistry and biology through examples.
- Defence and space questions pair a missile, satellite or mission with its year and organisation.
- Policy questions ask for the year, the body and the aim of schemes like STIP, the National Quantum Mission and BioE3.
- Health, environment and agriculture are on a separate page, with their own chapters.
Frequently asked questions
How many RAS Prelims practice MCQs are there on Science and Technology?
This page has 1113 practice MCQs on Science and Technology. Each has the correct answer, and most have an explanation.
Which chapters does the science and technology set cover?
Six chapters: basics of everyday science; computers, information and communication technology; defence and space technology in India; genetics, biotechnology and nanotechnology; science and technology policies and government programmes; and recent advances, Indian contributors and indigenisation.
Is science and technology part of the RAS Prelims syllabus?
Yes. The RPSC paper is called General Knowledge and General Science, and its syllabus lists science and technology topics along with environment, health, agriculture and government programmes, so questions can come from any of these areas.
How should I prepare science for RAS Prelims?
Revise the concepts by examples, then learn the missions, schemes and scientists with their year and organisation. Attempt each chapter, read the explanations and keep a list of the facts you missed.