KVS PGT Biology Mock Test - 6 - KVS PGT/TGT/PRT MCQ

विकल्प 1 "अज्ञान का अंधकार" सही है।व्याख्या

• 'तमसो मा ज्योतिर्गमय' उक्ति में ‘तमसो' का अर्थ है - अज्ञान का अंधकार।
• अन्य विकल्प निरर्थक हैं।

अन्य संबंधित बिंदु

• तमसो मा ज्योतिर्गमय का सामान्य अर्थ यह है कि अंधकार से प्रकाश की ओर चलो, बढ़ो।
• यह श्लोक बृहदारण्यकोपनिषद् से लिया गया है।
• विज्ञान की उपलब्धियों से मनुष्य रात के अंधेरे को दूर करने के उपाय खोजकर अपने को सुखी अनुभव कर रहा है। वैज्ञानिकों ने जो इस विद्युत् शक्ति का विकास किया है वह मानव जीवन में प्रकाश ले आयी है।

दिए गए विकल्पों में से शुद्ध वाक्य - संप्रति वह हवलदार है।व्याख्याअन्य विकल्प:

• अशुद्ध वाक्य - वह शायद अवश्य आएगा।
• शुद्ध वाक्य - वह अवश्य आएगा।
• अशुद्ध वाक्य - नेताजी मंच पर से बोला।
• शुद्ध वाक्य - नेता जी मंच पर से बोले।
• अशुद्ध वाक्य -अचानक उसके सीने पर दर्द हुआ।
• शुद्ध वाक्य - उसके सीने में अचानक दर्द हुआ।

अन्य संबंधित बिंदुशुद्ध और अशुद्ध वाक्य में क्या अंतर:

• हिंदी में वाक्य दो प्रकार के होते हैं: शुद्ध और अशुद्ध। यहां बताया गया है कि अंतर कैसे बताया जाए।
• शुद्ध वाक्यों में एक ही विषय और एक क्रिया होती है। अशुद्ध वाक्यों में एक से अधिक विषय और एक से अधिक क्रिया होती है।
• शुद्ध वाक्य वे हैं जो किसी भी त्रुटि या गलतियों से मुक्त हैं। दूसरी ओर, अशुद्ध वाक्यों में त्रुटियाँ या गलतियाँ हो सकती हैं।
• हिंदी में, कुछ अलग-अलग शब्द हैं जो यह दर्शाते हैं कि कोई वाक्य “शुद्ध” है या “अशुद्ध” है।

'हरिश्चंद्र होना' मुहावरे का अर्थ सत्यवादी होना है।

• मुहावरा - हरिश्चंद्र होना
  • अर्थ - सत्यवादी होना
  • वाक्य प्रयोग - अगर हम दूसरों को सच्चाई सिखाना चाहते हैं, तो हमें अपने सभी कामों में हरिश्चंद्र होना चाहिए।

अन्य विकल्प -

• नाराज़ होना का अर्थ - ग़ुस्सा होना
• मुहावरा - फूलना-फलना
  • अर्थ - धनवान होना

अन्य संबंधित बिंदु
मुहावरे के कुछ उदाहरण:- 

• मुहावरा - काठ का उल
• अर्थ - मूर्ख
  • मुहावरा - भात सड़ना
  • अर्थ - बिरादरी से निकालना
• मुहावरा - अंगारों पर पैर रखना
• अर्थ - जानबूझकर खतरे का काम करना
  • मुहावरा - घर-घर में माटी के चूल्हे होना
  • अर्थ - सब समान होना
• मुहावरा - सर्वनाश कर देना
• अर्थ - नामोनिशान मिटा देना

The correct answer is QWERTY.
Explanation

• QWERTY is a valid category of computer keyboard.
  • QWERTY is a keyboard layout for Latin-script characters.
  • The name comes from the order of the first six keys on the upper left letter row of the keyboard.

Important Points

• The keyboard is an input device.
• The keyboard is similar to an electric typewriter.
• The keyboard uses a serial port to connect to the computer.
• The keyboard only sends data to a computer and does not receive any information from it.
• Keys on the keyboard are of mainly three types:
  • Alphanumeric keys: Letters and numbers.
  • Punctuation keys: comma, period, semicolon, etc.
  • Special keys: Function keys, arrow keys, caps lock key, etc.

Other Related Points
Other Input and Output Devices-

To be an effective teacher, an individual has to develop several personal qualities and professional competencies which are too many and too complex to be acquired by a teacher on its own.

• An individual who wishes to be a teacher needs to be trained not only initially but also from time to time so that he/she will keep himself abreast.

Explanation

Before teaching, the teacher's training includes:

• to provide the would-be a teacher with proper understanding regarding the aims and objectives of education.
• to enable them to plan and present subject matter in a manner which will promote the interest, sense of purpose and and an understanding of pupil growth
• to develop understanding, interest, attitudes and skills, which would enable him promote all round development of children under his/her care.

Objectives are steps to be accomplished, lesson plans are basic models according to which teaching is done, and students; interests are telling what measures can be adopted to make teaching more effective.

Hence, a teacher ought to identify the objectives, prepare unique lesson plans and gather information about student’s interests before teaching.

Schools are complex places in which teaching is the most difficult and challenging part. Many Schools which do not have a clear and shared sense of purpose focused on student learning, find their teachers losing motivation, and improvement efforts failing.

• This happens because of the absence of a clear idea about the importance of work and duties. Without a clear sense of vision, direction, planning and decision-making about programs, curriculum, and instruction can remain uncoordinated.

Explanation

• The vision building of the school tells about the image of what the school can and should become. It is deeply embedded in values, hopes, and dreams whereas, the mission statement, it is more specific and often defines what the school is trying to accomplish and for whom.

Characteristics of vision statement:

• A compelling picture or image of what the school can become in the future.
• Connected to and articulates deeper values and hopes for the future.
• Needs to be translated into actions and plans that can be and are implemented.

Hence, a compelling picture or image of what the school can become in the future is known as Vision Building.

A curriculum can be called a plan for learning, which contains assumptions about the purpose of education in our society. It also has a definite structure through which the vision of the planners can be translated into learning experiences for the learner.

Explanation

• The Latin meaning of the term 'curriculum' is a racecourse used by chariots. Hence it is any path or course of study to be undertaken by an educational institution, to be covered in a specified timeframe. The course of events can take place inside the school and also outside it.
• A curriculum would consist of several events like a plan for learning, study periods, sports activities, cultural events, etc.
• Children acquire varied skills naturally while growing up in their environment. They also observe life and the world around them. When imported into classrooms, their questions and queries can enrich the curriculum and make it more creative.
• Such reforms will also facilitate the practice of the widely acknowledged curricular principles of moving from "known to the unknown", from "concrete to abstract", and from "local to global".
• Known to unknown: When the teaching starts from previous knowledge to new content to be taught, the learner does not find difficulty in moving from known to unknown. For example, suppose that you have planned to teach two-digit addition without carry over. Before starting to teach this, give the child single-digit sums to do ( which he had learned earlier) as a revision exercise. This would help the child in remembering and maintaining learned skills and will help him to learn the new task well.
• Children learn from concrete to abstract, i.e., the child learns about objects and events by handling them and experiencing them and if the child has had an adequate experience of handling objects directly as well as of pictorial activities, he can recall all the characteristics of the object just by hearing its name, even though the object or its picture is not there before him. This is because he has formed a mental image of that object, based on his experiences during the concrete and pictorial stage. He can think about it without seeing it - in other words, he can think of it in abstraction.
• The curriculum is designed in such a way that it caters to the mental ability of the child according to his\her age, the concept of local to global is used while designing the curriculum so that in early stages, the children learn about the knowledge of regional aspects like national leaders, geography of the country and also its political history but as they move in higher standards they also start learning about global events like world wars and French Revolution which have played significant role in the development of society.

Thus, it is concluded that the curriculum in schools should follow the curriculum principle of moving from concrete to abstract and from local to global.

Constructivism represents a view that emphasizes the active role of the learner in building, understanding, and making sense of information. Constructivism represents an approach embedded with the central principle that learners can only make sense of new situations in terms of their existing understanding. ExplanationFollowing classroom activities facilitate constructivist teaching-learning processes:-

• Students taking the initiative in providing solutions to classroom problems are actively involved in the learning process. Hence constructivist learning is taking place.
• Expecting students to answer from their own words and contextual examples also involves the active involvement of the learners. Hence constructivist learning is taking place.

Thus, it is concluded that Only A and C are the correct options.Hint

• Using textbooks as the only teaching-learning material in the class does not include students actively in the construction of knowledge.
• Choosing assessment activities mainly centered around board examination patterns does not include any engagement by students. So, constructivist learning is not taking place.​

Other Related PointsConstructivist learning includes:

• Reciprocal teaching/learning. Allow pairs of students to teach each other.
• Inquiry-based learning (IBL) Learners pose their own questions and seek answers to their questions via research and direct observation.
• Problem-based learning (PBL).
• Cooperative learning.

Adolescence is a phase of life of a person when he is no more a child and not yet adult. The life is full of tremendous energy. The curiosity and experimentation at one time paves the path to success and at other, may cause uncertainty. This is a critical time in life because the experiences, knowledge and skills acquired in adolescence have important implications in adulthood.

ExplanationAdolescents need to find their place in society and gain a sense of fitting in it. This is a process of socialization involving an adolescent’s integration with society. This process socialization enhances the sense of personal identity, and the development of personal identity helps the adolescent to deal with society’s expectations and standards and norms. This challenges the adolescent to make changes in social behaviour.

• Society’s expectations pose a challenge for adolescents and are valuable in helping them to progress along the path to adulthood. The fulfilment of these expectations helps to develop a positive sense of self.
• Adolescents who are over-whelmed by society’s expectations may revert to anti-social behaviour ranging from low-level delinquency to serious crimes.
• Parental expectations to perform and confirm to their standards are abnormally high or unrealistic. They may generate negative feelings, communication gap and anti-social behaviour.
• Adolescent expectations in relationships with peers, parents and society are often not fulfilled and cause conflicts.
• Moving away from dependence on parents and family and having close relationships with friends is a major social change. Parental control leads to conflicts and communication gap. Peers determine the flow of an adolescent’s life and develop their personality too.

Hence, it can be concluded that 'Relationship with parents' can have a significant impact on the social competence of an adolescent.

Vygotsky is known as the proposer of social constructivism. The Social Constructivism approach talks about the importance of social interaction and context in learning.

Explanation

• Vygotsky regards knowledge as a social construct thus emphasizes the importance of peer group learning, reciprocal learning, collaborative learning, etc.
• Vygotsky recognizes that learning always occurs and can't be separated from a social context. Children learn effectively when they participate in a wide range of challenging activities along with peers to jointly construct knowledge.
• Peer collaboration is the educational approach of using groups to enhance learning through working together. It is a collaborative form of learning that is based on interaction, discussion, and knowledge sharing among peers.
• In Peer collaboration, groups of two or more learners work together to solve problems, complete tasks, or learn new concepts. This approach actively engages learners to process and synthesize information and concepts, rather than using rote memorization of facts and figures.

Hence, we can conclude that to facilitate students' learning, Peer Collaboration is suggested by Lev Vygotsky in his theory of social constructivism.

Growth leads to the development of personality and behavioral traits, which is called maturation. In general, as organisms grow inside the structure, it is less quantitative and more emotional and cerebral. An illustration would be brain growth which makes it possible to manage activities that are more complicated.Explanation

• The maturation stage marks the end of growth and the consolidation of acquired mental, social, and emotional development. In essence, maturation is a process of internal improvement, alteration, and development of an organism's potential. Being mature is a necessary prerequisite for learning. So, Maturation is a developmental process.
• Learning is the development that results from effort and repetition. We are aware that learning and maturation interact to influence development. The constraints of maturation are imposed on growth. It suggests that even when learning is fostered, growth cannot advance past a certain point due to limitations in hereditary endowment. So, Maturation and learning work together to promote the development of an individual.
• For example, bicycle riding will be learnt only as a result of effort, practice and training.

Hence, it is concluded that Both A and B are true.

Cognitive development is a part of the development which involves developing the capacity of how children to think, explore, solve problems, remember, take decisions, reason, etc.

• The development of skills and knowledge is cognitive development.

Explanation

• The math skills area gives a rough idea about the student's cognitive development.
• Solving math problems require developed problem-solving skills and exploring skills, which are aspect of cognitive development.
• Math is a subject which involves solving equations, trial and error methods, thinking outside of the box, and other advance cognitive processes.
• Math also allows for the enhancement of the cognitive skills of the individual.
• Math enhances the reasoning skills, intelligence, and memory of children.

Thus, it can be concluded that the math skills area gives a rough idea about the student's cognitive development.

Lev Vygotsky, a Russian psychologist and a contemporary of Jean Piaget proposed a theory of cognitive development known as the ‘Socio-Cultural Theory’.
Explanation

• According to Vygotsky, social interaction is the primary cause of learners' development as his theory emphasizes that children learn through interaction and collaboration with skilled and knowledgeable people.
• The society and culture of the children play a vital role in the development of their cognition.
• The sign system or the language of society works as a tool for gaining knowledge.
• Inputs from others and especially from more knowledgeable people and adults have the capacity to affect the development of cognition.

Thus, it is concluded that according to Vygotsky, cognitive development depends on social interactions.
Other Related Points
There are three ways discussed in his theory that help a child in shaping his/her ideas: the zone of proximal development, scaffolding, and private speech.

Constructivism is centered on the idea that human knowledge and learning are actively constructed by the learner, not passively received from the environment.

Socio-constructivist frame: Students have also to include the social and cultural settings, in which they learn and which also have an impact on students as they change their ideas. From this perspective, sometimes referred to as ‘situated cognition, the cultural and the social background of students, use of language, and how meaning is derived from various contexts play a role in the students’ construction of ideas.

Explanation The characteristics of the socio-constructivist frame as-

• Knowledge is not fully known and fixed.
• Knowledge is not a thing that exists out there but is personally and socially constructed.
• The learner plays an active role in the personal creation of knowledge through interacting with their socio-cultural context.
• Knowledge construction rather than knowledge reproduction is emphasized.
• Learning is a social process in which the learner constructs meaning that is influenced by the interaction of prior knowledge and new learning events.
• It acknowledges the uniqueness and complexity of the learner.
• By all these references we can consider that Children are active beings who construct knowledge by acting upon and interacting with their socio-cultural context from a socio-cultural perspective.

Hint

• Children's behavior changes by constructing knowledge by their experiences or previous knowledge but not totally.
• Children do not have any knowledge at the time of birth, they can acquire and learn by interaction with the environment or by learning.

Other Related Points Lev Vygotsky explains the role of society in his theory of socio-cultural development According to Lev Vygotsky, the development of children depends on three factors.

• Social interaction- Society plays an important role in the development and knowledge gained by the child.
• Language- Language development in a child should be done by the environment, engagement in family, etc.
• Culture - culture plays an important role in the development of a child, a child behaves as same as they learn from their culture, society, and environment.

Concept:

• Assisted reproductive technologies or ART refers to the special techniques that are used to deal with infertility.
• The cause of infertility may be - physical, congenital, immunological, psychological, diseases or drugs.
• Specialized infertility clinics help in diagnosis and corrective treatments of couples to enable them in conceiving.
• Sometimes, medical assisted procedures are required for a couple to bear children.
• These ART procedures aim to resolve the specific issue that is restricting pregnancy.

Important Points

• GIFT stands for Gamete intra-fallopian transfer, which one of the ART procedures to help with infertility issues.
• It involves the transfer of ovum into the fallopian tube of the female.
• The ovum is collected from a female donor.
• The ovum is transferred to the fallopian tube as that is where fertilization takes place.
• It is effective for a female:
  • who cannot produce a gamete (ovum), but
  • who can provide a suitable environment for fertilization, and
  • who can retain the fertilized zygote or embryo inside the uterus.

Other Related PointsSome other ART methods:

• ZIFT -
  • Zygote intra-fallopian transfer is the transfer of the embryo, with less than 8 blastomeres, into the fallopian tube.
  • This is performed after in-vitro fertilization of sperm and ovum.
  • The zygote is formed under simulated conditions in the laboratory (test tube).
  • It is effective for a female who cannot provide suitable environment for fertilization, but can retain the zygote in the uterus.
• IVF -
  • In vitro fertilization or IVF is the fertilization of sperm and ovum outside the body in laboratory conditions that is similar to that of the body.
  • The ovum from the female and sperm from the male are collected.
  • The gametes are then induced to fertilize and form zygote under simulated conditions in the laboratory (test tube).
  • The next step is embryo transfer, where the fertilized zygote is transferred to the female body.
• IUT -
  • Intra-uterine transfer is the transfer of embryo with more than 8 blastomeres into the uterus, where implantation takes place.
  • This is also an important part of IVF.
  • The ZIFT and IUT are types of embryo transfer techniques.
  • This method is also applicable for females who cannot provide suitable environment for fertilization, but can retain the zygote in the uterus.
• ICSI -
  • Intra-cytoplasmic sperm injection is a method by which the sperm is directly injected into the ovum.
  • It is a specialized procedure to form an embryo in-vitro.
  • It is effective where the male sperm is unable to fertilize the ovum normally due to low motility, etc.

Concept:
Human circulatory system:

• The organ system of human beings or other organisms which is responsible for the transport of materials inside the body is called the circulatory system.
• Our circulatory system consists of a muscular pumping organ called the heart, arteries, veins, capillaries, and blood.
• The heart has two atria and two ventricles.
• The heart acts as a pump to push out blood.
• The arteries, veins, and capillaries act as tubes or pipes through which blood flows. These tubes which carry blood are called blood vessels.
• Arteries carry oxygenated blood away from the heart except the pulmonary artery carries deoxygenated blood.
• Veins carry deoxygenated blood away from the heart except the pulmonary veins carry oxygenated blood.

Explanation:

• For double circulation, there are 2 circulatory pathways:
  • Systematic circulation
  • Pulmonary circulation
• Systematic circulation
  • It carries oxygenated blood from the heart to all parts of the body through a complex system of arteries and capillaries.
  • It also carries deoxygenated blood from these organs back to the heart through veins.
• Pulmonary circulation
  • After the heart receives the deoxygenated blood from different parts of the body, it pumps blood to the lungs for expelling the CO₂ and collecting oxygen.
  • After that, the oxygenated blood is sent back to the heart for systematic circulation.
• Thus, the systematic circulation carries blood from the heart to all the other parts of the body and back again. Hence, statement 1 is incorrect.
• And, the pulmonary circulation is a short loop from the heart to the lungs and back again. Hence, statement 2 is incorrect.

Therefore, the correct answer is Statements 1 and 2 are wrong.Other Related Points

• Open circulatory system: Examples- insects. and prawns etc.
• Closed circulatory system: Examples- mollusks, echinoderms, and all vertebrates.

Concept:

• The corpus luteum is a temporary endocrine gland in the human body.
• After the ovulation from a ruptured follicle, it is developed, during the luteal phase.
• The phase at which the body prepares for the implantation of a fertilized egg is called the luteal phase.
• At the site of a follicle, or sac, the corpus luteum is formed inside the ovary.
• Until the fetus is producing adequate levels to sustain the pregnancy, the corpus luteum continues to produce progesterone
• Human chorionic gonadotropin or HCG maintains the corpus luteum.
• The size of the corpus luteum starts decreasing after 10 weeks of pregnancy.

Explanation:

Option 1: Corpus allatum – INCORRECT

• Corpus allatum is an endocrine gland of insects that plays a vital role in metamorphosis.
• Hence, this option is incorrect.

Option 2: Pineal gland – INCORRECT

• The pineal gland is a permanent gland of the human body that deals with the sleep cycle and solar cycle etc.
• Hence, this option is incorrect.

Option 3: Corpus cardiacum – INCORRECT

• Corpus cardiacum is one of the fused bodies that deal with the brain hormones in insects.
• Hence, this option is incorrect.

Option 4: Corpus luteum – CORRECT

• The corpus luteum is a temporary endocrine gland in the human body that secretes progesterone.
• Hence, this option is correct.

So, the correct answer is option 4).

The correct answer is option 3.

Concept:

• Plants that are adapted to dry tropical regions have the C4 pathway.
• C4 plants have a special type of leaf anatomy, they tolerate higher temperatures, they show a response to high light intensities, they lack a process called photorespiration, and have greater productivity of biomass.

Explanation:

• Plants in tropical desert regions commonly follow the C4 pathway.
• Here, a 4-carbon compound called oxaloacetic acid (OAA) is the first product of carbon fixation. Such plants have certain adaptations as well.
• The primary CO2 acceptor is a 3-carbon molecule, phosphoenol pyruvate (PEP), and is present in the mesophyll cells.
• The enzyme responsible for this fixation is PEP carboxylase or PEPcase.
• PEP is a 3C compound that serves as the primary CO2 acceptor in the mesophyll cell cytoplasm of C4 plants like maize, sugarcane, Sorghum, etc.
• Mesophyll cells of C4 plants lack the RuBisCO enzyme. The C4 acid OAA is formed in the mesophyll cells.

So, option 3 is correct.

The correct answer is Absorption of water.

Explanation

• The function of Velamen is the Absorption of water.
• Velamen is spongy, multiple epidermises that cover the roots of some epiphytic or semi epiphytic plants, such as orchid and Clivia species.
• The velamen of an orchid is the white or gray covering of aerial roots.
• It is many cell layers thick and capable of absorbing atmospheric moisture and nutrients.
• Often, the roots of orchids are associated with symbiotic fungi or bacteria.
• The latter may fix nutrients from the air.
• This functionality allows the orchid to exist in locations that provide a reproductive or vegetative advantage such as improved exposure or reduced competition from other plant species.
• The velamen also serves a mechanical function, protecting the vascular tissues in the root cortex, shielding the root from transpirational water loss, and in many cases, adhering the plant to the substrate.
• So, velamen is meant for the absorption of water.

Concept:

• Peristome derived from greek word – ‘peri’ meaning ‘around’ and ‘stoma’, meaning mouth.
• The peristome is a teeth–like projection that surrounds the mouth of the capsule in most of the members of Bryidae (Mosses) of bryophytes. So, it is an important characteristic of Bryopsida.
• The peristome teeth spring from the rim or diaphragm.
• The peristome teeth are triangular two-ply structures that operate like trap – doors.

Functions:

• Peristome teeth serve as a valve that allows the spores to exit the capsule.
• The peristome teeth open and spread outwards during times of low humidity, allowing the spores to float away and disperse. One layer readily absorbs and releases water, while the other layer does not react much to varying humidity levels.
• This causes the teeth to bend outward during times of low humidity.

Mainly Peristome teeth are of two types:

1. Orthodontous
2. Nematodontous

Explanation:

• Funaria belongs to the group Bryophyta.
• Funaria is a type of Moss commonly called Rope moss or Cord moss.
• Its sporophyte is divided into Foot, Seta, and Capsule.
• The capsule has a layer called an operculum, which has 32 teeth, arranged in 2 rings of 16 teeth each
• These peristome teeth are of Arthodontous type (when there are 16 teeth in each peristome)

Other Related Points

• Nematodontous – In nematodontous peristome, the teeth of peristome are solid, composed of bundles of dead cells.
• Eg – Polytrichum, Pogonatum

Concept:

• About 99.9 percent of the base sequences in human DNA are similar.
• The remaining 0.1 percent differences in the DNA are unique in the individuals.
• These differences are responsible for the unique phenotypic appearance of human beings.

Important Points

• DNA fingerprinting advantages:
  • DNA fingerprinting is a very quick way to compare the DNA sequences of two individuals.
  • It is useful in solving criminal cases, parental disputes, etc.
• Repetitive DNA
  • DNA fingerprinting is based on spotting the variations in certain regions of DNA called repetitive DNA.
  • These regions are called repetitive because a small stretch of DNA is repeated multiple times.
  • Density gradient centrifugation ( a process in which constituents of samples are separated based on density) is used to separate repetitive DNA from bulk genomic DNA.
• Satellite DNA
  • In density gradient centrifugation, bulk DNA forms large peaks while other small peaks are due to satellite DNA.
  • It is a sequence of DNA that is highly repetitive.
  • It is classified into two categories: microsatellites and minisatellites.
  • This classification is based on the base sequences repeated, the length of the segment, and the number of repetitive units.
• ​DNA polymorphism
  • ​Polymorphism is the occurrence of a substance/organism/nucleic acid sequence in more than one form.
  • DNA polymorphism is variations in DNA sequences in a population as a result of inheritable mutations.
  • In DNA polymorphism inheritable mutations occur in a population at a higher frequency.
• Single nucleotides
  • It consists of a base (A, T, G, C), a molecule of sugar, and a phosphoric acid molecule.
  • It is the building block of DNA.

So, the correct answer is option 3.

Correct answer is cotton.ExplanationBt toxin -

• Bt stands for Bacillus thuringiensis.
• Bt toxin gene is present in a bacteria, B. thuringiensis.
• This bacteria produces toxins against lepidopterans (tobacco budworm, armyworm), coleopterans (beetles), and dipterans (flies, mosquitoes).
• During a particular phase of their growth, B. thuringiensis forms protein crystals.
• These crystals are insecticidal.
• They are inactive inside the bacteria as pro-toxin.
• When a target insect ingests it, it converts into an active form due to the alkaline pH in the gut of these insects.
• The active toxin binds to the surface of the midgut epithelial cells and creates pores in the gut of the insect.
• It causes swelling and lysis and the insect dies.

Concept:
Bt cotton -

• Bt toxin gene were isolated from Bacillus thuringiensis and incorporated into crop plants that are prone to infestation of these insects.
• This was done using recombinant DNA technology.
• There are specific Bt genes against specific insects.
• The toxin coded by genes named cryIAc and cryIIAb are effective against cotton bollworm, and cryIAb is effective against corn borer.
• The Bt toxin gene has been cloned from the bacteria and has been expressed in plants.
• This lets the plant express Bt toxin and kills the insects attacking them.
• It provides resistance from insects without the need for insecticides; in effect resulting in a bio-pesticide.

Although other Bt crops have also been produced by genetic engineering, ​Bt cotton is the only Bt crop grown by farmers in India.

Concept:

• Stomata are the minute-pore-like structure bound by the guard cells that are present on the leaf surface.
• Transpiration takes place through stomata.
• Stomata open up during the daytime and close at night barring some exceptions.
• In cacti and other succulent plants stomata remain closed during the day and open at night. This is to avoid loss of water through transpiration.

Important Points

• Stomatal movement is governed by the guard cells.
• The opening and closing of the stomata are depended on the turgor changes of the guard cells. Cells become rigid because of the turgor pressure.
• During the daytime, endosmosis (movement of solvent inside the cell) causes the guard cells to become turgid. This exerts turgor pressure on the walls of the guard cells.
• The turgor pressure causes the lateral walls of the guard cells to stretch out. This in turn pulls apart the inner thin walls and opens the stoma.
• There are cellulose microfibrils in the cell wall of the guard cells. These are arranged radially.
• This arrangement of the microfibrils helps in the proper opening of the guard cells.
• The microfibrils constrain the opening in the guard cells only in the lengthwise direction when the cells are turgid. This cause the cells to separate and the stoma to open up.
• As a result, water is lost in the form of water vapor through the stomatal opening.

Explanation:

• Option 1: Longitudinal orientation of cellulose microfibrils in the cell wall of guard cells - INCORRECT
  • ​The cellulose microfibrils are arranged radially in the cell wall of the guard cells.
• Option 2: Contraction of the outer wall of guard cells - INCORRECT
  • ​The opening and closing of the stomata are governed by the guard cells.
  • Expansion of the guard cells opens the stomata.
  • Contraction of the guard cells on the other hand closes the stomata.
• Option 3: Decrease in turgidity of guard cells - INCORRECT
  • ​Endosmosis causes the cells to become turgid.
  • As a result of the increase in turgidity of the cells, stomata open up and transpiration takes place.
  • A decrease in turgidity however causes the stomata to close up.
• ​Option 4: Radial orientation of cellulose microfibrils in the cell wall of guard cells - CORRECT
  • ​The cellulose microfibrils in the cell wall of the guard cells are arranged radially, helping in the opening of the stomata.

So the correct answer is option 4.

Explanation:

• The evolution theory is based on similarities between different organs and the way the complexity in organs has increased.
• There are certain living beings that have the property of two or more classes.
• The arrangements of animals according to evolution.
• Animals without backbone ⇒ Fishes ⇒ Amphibians ⇒ Reptiles ⇒ Aves ⇒ Mammals.
• Archaeopteryx is the connecting link between Reptilia and Aves.
• Reptilia is a class of reptiles like snake, lizard etc. and Aves is the class of bird.
• Archaeopteryx had some features beak, wings, the structure of legs, etc. were similar to Aves (bird).
• And some characteristics like beak, tail, scales on the body, etc. were similar to reptiles.

Other Related PointsPlatypus and echidna are the connecting links between Reptilia and Mammalia.

Correct answer: 2)
Concept:

• Competition is a type of population interaction in which two species fight for the same resources.
• It is of two types- interspecific competition (between two different species) and intraspecific competition (within the same species).

Explanation:

• Option 1:
• Predation is a type of interaction in which one organism kills and eats up the other organism.
• The one who kills is a predator and the other one who is eaten up is known as prey.
• Option 2:
• Resource partitioning is a method in which species striving for the same resources use resources differently.
• It is most common in interspecific competition.
• This allows the coexistence of species and avoids competition.
• MacArthur showed that five closely related species of warblers living on the same tree were able to avoid competition and co-exist due to behavioral differences in their foraging activities.

• Option 3:
• The competitive release is a method in which a particular species restricts itself in a particular area due to the presence of its competitive species.
• When that competitive species is removed, they will expand their area.
• Option 4:
• Mutualism is a population interaction where two species live in close association with each other and benefit each other through their interaction.

So, the correct answer is option 2.

The correct answer is Zymase.

Explanation

• Yeast when grows in the sugar solution example like the juice of sugarcane, dates, grapes, etc important enzymes decompose the sugars with the help of a composite zymase to convert it into alcohol and carbon dioxide.
• The Zymase enzyme is produced naturally within yeast cells.
• It occurs naturally in yeasts. It is an enzyme complex that catalyzes the fermentation of sugar into carbon dioxide and ethanol.
• Zymase activity varies among yeast strains. It is also the brand name of the drug pancrelipase.

Concept

• The complex permanent tissue can be divided into two types - Xylem & Phloem
• Xylem is further divided into Primary Xylem & Secondary Xylem
• Primary Xylem - It is the first formed Xylem. It originates from the Procambium. It developed into two forms - 1st form protoxylem while the latter form is metaxylem
• Secondary Xylem - It is called the wood, and is derived from vascular cambium. At the time of secondary growth secondary xylem is developed as a two system.

1. Axial System - Tracheids, Vessels, Xylem fibres & Xylem Parenchyma
2. Radial Xylem - Ray Parenchyma

Explanation

• Tyloses are the balloon-like outgrowth formed by the parenchyma of the secondary xylem in the lumen of the vessels.
• During stressful conditions falls and "dam" up the vascular tissue to prevent the further damage

Concept-

• ​During seismonastic movements (also known as rapid plant movements) in Mimosa pudica, turgor changes primarily occur in the pulvinus leaf base
• Mimosa pudica, also known as the "sensitive plant" or "touch-me-not," is a plant known for its rapid folding and drooping of leaves in response to touch, shaking, or other stimuli. This movement is a type of seismonastic movement.
• The pulvinus is a specialized swollen structure located at the base of the leaflet or petiole in certain plants, including Mimosa pudica. It acts like a hinge and is responsible for the movement of the leaflets.

Mechanism of Seismonastic Movement:

• Stimulation: When the leaf of Mimosa pudica is touched, shaken, or subjected to another form of mechanical stimuli, an electrical signal called an action potential is generated in the plant.
• Propagation of Signal: This electrical signal travels through the plant's cells to different parts of the leaf.
• Turgor Changes: The pulvinus contains motor cells that regulate the water pressure (turgor pressure) inside the cells. When the signal reaches the pulvinus, it triggers a rapid movement of ions, primarily potassium ions (K⁺), out of the motor cells. Water follows these ions out, causing a sudden loss of turgor pressure.
• Movement: The decrease in turgor pressure in the cells on one side of the pulvinus causes the cells to become flaccid. Meanwhile, cells on the opposite side retain their turgor pressure, resulting in an imbalance but enabling the leaflet to fold and droop.

Concept:

• R.H. Whittaker proposed the Five Kingdom System of Classification.
• According to R.H. Whittaker's Five Kingdom system, the living organisms are divided into the following Kingdoms -
  • Kingdom Monera
  • Kingdom Protista
  • Kingdom Plantae
  • Kingdom Fungi
  • Kingdom Animalia
• Kingdom Protista includes all unicellular eukaryotic organisms.
• This Kingdom shows a link with the remaining eukaryotic Kingdoms - Fungi, Plantae, and Animalia.
• Chrysophytes, Dinoflagellates, Euglenoids. Slime molds and Protozoans are grouped under Kingdom Protista.
• Examples: Paramoecium, Euglena, Amoeba, Oodinium, etc.

Explanation:

Slime molds -

• ​Slime molds are unicellular eukaryotic organisms belonging to the Kingdom Protista.
• They either live as a single cell or aggregate together to form multicellular organisms.
• They are saprophytic organisms. It obtains its nutrition by absorbing organic material.
• When food is available, slime molds exist as single-cell fruiting bodies that bear spores at their tips.
• Whereas in scarcity of food slime molds form aggregates and live in colonies.
• The aggregates of slime molds formed are called plasmodium.
• Plasmodium slime molds may grow and spread over several feet.
• The plasmodium slime molds contain cytoplasm with an undivided plasma membrane.
• The cells do not have a cell wall and have a naked cytoplasm.
• The cytoplasm contains multiple nuclei.
• Slime molds are extremely resistant and can survive for many years even in adverse conditions.

So from the above-given information, the correct answer is option 4.

The correct answer is option 1, i.e. Glycosidic Bond.

• Lactose is a disccharide made up of Glucose and Galactose.
• It is found in Milk.
• There are only three types of Glycosidic bond present:
  • 1,2 Glycosidic bond- Sucrose(Glucose + Fructose)[only found in sucrose]
  • 1,4 Glycosidic bond- Maltose(Glucose + Glucose)
  • 1,6 Glycosidic bond-Isomaltose (Glucose + Glucose)
• The peptide bond is found in protein chains.
• Ester bond is found in fat or lipid molecules.