MPTET Varg 1 Biology Mock Test - 1 - MPTET MCQ

''Learning and knowledge are the greatest assets of a man'

• उक्त वाक्य का सही हिंदी रूपांतरण होगा -."सीख और ज्ञान मनुष्य की सबसे बड़ी सम्पत्ति है।"
• अन्य विकल्प अनुचित है।

स्पष्टीकरण
वाक्य के महत्वपूर्ण शब्दों का हिंदी अनुवाद -

• Learning - सीखना
• knowledge - ज्ञान
• greatest - महानतम।
• assets - सम्पति

अन्यसंबंधित बिंदु
assets शब्द से बने अन्य वाक्य -

• The river is a real asset. - नदी एक वास्तविक संपत्ति है।

सही उत्तर है - ‘निर्मम’।

• ‘जो ममत्व से रहित हो’ उपयुक्त वाक्यांश के अर्थ को व्यक्त करने वाला सही शब्द ‘निर्मम’ होगा।

स्पष्टीकरण
अन्य विकल्प :

• जिसे कोई रोग न हो : निरामय।
• अनुराग न रखनेवाला : निर्मोही।
• जिसमें दया न हो : निष्ठुर।

महत्वपूर्णबिंदु
अन्य महत्वपूर्ण वाक्यांश के लिए एक शब्द :-

• जो किसी भी गुट में नहीं हो – तटस्थ।
• ईश्वर में आस्था रखने वाला – आस्तिक।
• ऊपर कहा हुआ – उपर्युक्त।
• जो परीक्षा में पास न हो – अनुत्तीर्ण।

अन्यसंबंधित बिंदु

• किसी वाक्य में प्रयुक्त या स्वतन्त्र, किसी वाक्यांश के लिए किसी एक शब्द का प्रयोग किया जाता है,
  जो उस वाक्यांश के अर्थ को पूरी तरह सिद्ध करता हो तो उसे वाक्यांश के लिए एक शब्द कहते हैं, अर्थात
  अनेक शब्दों के लिए एक शब्द को प्रयुक्त करना ही वाक्यांश के लिए एक शब्द कहलाता है।

The correct answer is 'A secret enemy'.

Explanation

• The expression 'the snake in the grass' is used to refer to a person who pretends to be good, well wisher but can't be trusted.
• This idiom is used to refer to a person who has chances of cheating.
  • For example: Ravi is a snake in the grass, I prefer not the discuss the upcoming project with him.
• Thus, option 4 is the correct answer.

The correct answer is 'a'.

Explanation

• The most appropriate article to fill in is 'a'. Article 'a' is an indefinite article.
• If the noun is modified by an adjective with a consonant sound, then the article 'a' will be used.
• The phrase 'a few' means not many, a small number of. It is used with plural countable nouns.
  • ​Example: There are a few books on the shelf.

Therefore, the correct answer is Option 4.

Other Related Points

• Let's understand the meanings of the other articles:
  • An: It is an indefinite article. It is used before nouns that begin with a vowel sound. It is also used with a singular count noun whose specific identity is not known to the reader.
  • The: It is a definite article. It is used with any noun(whether singular or plural, count or uncount) when the specific identity of the noun is known to the reader.

Let Ajay and Lalit's ages be a and b years respectively.

Statement 1:

⇒ (x + y)/2 = 34

⇒ x + y = 68 ----(1)

Statement 2:

After 14 years,

⇒ (x + 14) = 2(y + 14)

⇒ x + 14 = 2y + 28

⇒ x – 2y = 14 ----(2)

By solving equations (1) and (2) we can get the respective age of Ajay and Lalit

∴ Statement 1 and 2 together are sufficient

Explanation:

• Civil Disobedience movement is one of the most popular events in the history of the Independence movements of India.
• It was also called passive resistance.
• Civil Disobedience is defined as the refusal to obey the demands or commands of a government by the citizens.
• Civil Disobedience movement was started by Mahatama Gandhi in 1930.
• It was started when Gandhi left Sabarmati Ashram at Ahemadabad along with his 78 followers of Ashram for Dandi on 12 March 1930.
• After reaching Dandi, Gandhi broke the salt law.
• After this it hurts the monopoly of the British Government to make salt.
• The civil disobedience movement get Nationwide acceptance at that time.
• This movement becomes symbolic of people's defiance of the British government policies.

Thus, the Civil Disobedience movement took place in the year 1930.

Language skills are necessary for effective communication in any environment and to interact with others. The four basic language skills and their natural order are listening-speaking-reading-writing.

• Listening is the most important skill to promote active communication. It is the ability to accurately identify the sounds of speech to interpret messages for meaningful communication.

Explanation Type of Listening Skills:

Responsive Listening:

• Responsive listening falls under the category of reciprocal listening for it requires a response from the listener in order to continue with the communication. The listener has to pay attention to the speaker’s words in order to make an appropriate response.
• This requires a different mindset and can be practiced by creating situations where the students participate in a discussion or have a conversation.

Attentive Listening:

• It is a type of listening in which the listener has to pay close attention to what is being said and stop to ask questions, sum up what the speaker says in order to confirm if he/she has understood correctly or even ask the speaker to repeat what he or she said.
• A teacher can develop activities based on directions and instructions such as when students carry out an experiment, or a process following the instructions step by step.

Passive Listening:

• This kind of listening happens when our attention is partially divided like when children are doing their homework with the television turned on in the background, or when students are discussing in different groups within the classroom.
• There is a momentary ‘tuning out’ but there is enough consciousness to return to the activity on hand. In the classroom, the teacher’s voice alerts students to attention. This happens on many occasions in real life.

Hence, it is clear that detailed listening is not a type of listening.

A lesson plan is a teacher’s daily guide for what students need to learn, how it will be taught, and how learning will be measured. Lesson plans help teachers be more effective in the classroom by providing a detailed outline to follow each class period.

Explanation

Some of the major characteristics of an ideal lesson plan:

1. Level of Class:

• an effective lesson plan must feature the class of learners for which the lesson is being designed.
• This will serve as the background to every other thing that will go into planning the lesson.
• The language of the lesson, especially, depends so much on the class of learners.

2. Length of the Lesson:

• a good lesson must have a clearly stated time span.
• This will help the teacher determine the amount of content the lesson can take.
• Be flexible: if something actually takes longer than anticipated, take time to finish the main lesson aim and drop secondary aims.

3. Objectives:

• The objective is the overall idea of what the teacher set to achieve in the lesson.
• The objective is what the teacher think students should be able to do better by the end of the lesson.
• Having the aim in mind will prevent from losing focus or just teaching the favourite topics.
• Some lessons may require more than one objective.
• The objective should be written at the top of the lesson plan to serve as a guide to other things that will go into the plan.
• Clear and realistic objectives are essential if a lesson is going to be successful.

4. Assumptions:

• this is also called presumed student knowledge or previous knowledge.
• This aspect of the lesson plan deals with what students have already covered in previous lessons or courses and so should be familiar with.
• This emphasizes the point that lessons should be part of an overall syllabus or structure, with links not just within a single lesson, but between different lessons.

Hence, An ideal lesson plan is based on teaching levels, Objectives, and previous knowledge.

Concept

• A large number of couples all over the world including India are infertile, i.e., they are unable to produce children in spite of unprotected sexual cohabitation.
• Specialised health care units (infertility clinics, etc.) could help in the diagnosis and corrective treatment of some of these disorders and enable these couples to have children.
• Where such corrections are not possible, the couples could be assisted to have children through certain special techniques commonly known as assisted reproductive technologies (ART).

Explanation

• Intracytoplasmic sperm injection (ICSI) is the specialised procedure to form an embryo in the laboratory in which a sperm is directly injected into the ovum.
• In ICSI, single live sperm is injecting directly into the centre of a human egg.
• The ICSI technique is used to help those couples in fertilization with severe male factor infertility.

Therefore the method of directly injecting sperm into the ovum in Assisted Reproductive Technology is called ICSI.

Other Related Points

GIFT - (gamete intrafallopian transfer): Transfer of an ovum collected from a donor into the fallopian tube of another female who cannot produce one but can provide a suitable environment for fertilization and further development.

ZIFT - (zygote intrafallopian transfer): The zygote or early embryos (with up to 8 blastomeres) could then be transferred into the fallopian tube (ZIFT–zygote intrafallopian transfer) and embryos with more than 8 blastomeres, into the uterus (IUT – intrauterine transfer), to complete their further development.

ET - (embryo transfer): In this method, popularly known as the test-tube baby programme, ova from the wife/donor (female) and sperms from the husband/donor (male) are collected and are induced to form zygote under simulated conditions in the laboratory.

Explanation

• Sickle-cell anaemia is caused by a point mutation that causes a substitution of amino acid.
• The β-globin chain of haemoglobin (Hb) has Glutamic acid at the 6th position of its peptide chain.
• This Glutamic acid (Glu) is substituted by Valine (Val) due to the point mutation.
• A single base pair of A-T in the normal Hb gene (Hb^A) is replaced by T-A in the mutated gene Hb^S.
• Thus, the DNA sequence that is transcribed changes from CTC to CAC.
• The CAC codon is transcribed to GUG in the mRNA.
• The GUG codon of mRNA is then translated into Valine (Val).
• Therefore, the Glu is changed to Val in haemoglobin of sickle-cell anaemic patients.

Important Points

• Sickle cell anaemia is a genetic disorder that affects the red blood cells (RBCs) of the body.
• The shape of the RBCs changes from biconcave disc to an elongated sickle-like shape.
• This effect does not allow enough oxygen to be carried to different organs for normal functioning.
• It is common in the African population.
• The malarial pathogen Plasmodium uses the RBCs to reproduce asexually and rupture them, causing malarial fevers.
• The change in shape of RBCs restricts the infection of Plasmodium.
• Thus, it is believed that people with sickle-cell anaemia is less prone to malaria.

• Phosphoenolpyruvic acid or PEP is a compound that serves as primary acceptor in the mesophyll cell cytoplasm of plants like maize, sugarcane, Sorghum etc.
• These plants are known as C4 plants that are specially adapted for CO₂ fixation at its lower concentrations, like when the stomata are closed to reduce transpiration.

Explanation

• In the C4 plants, two pathways run for CO₂ fixation - C3 Cycle or Calvin cycle & C4 Cycle or Hatch and Slack Pathway.
• The primary CO₂ acceptor is 3-carbon molecule phosphoenolpyruvate (PEP) and is present in the mesophyll cells.
• The enzyme responsible for this fixation is PEP carboxylase or PEPcase.
• It is important to register that the mesophyll cells lack the RuBisCO enzyme.
• The C4 acid Oxaloacetate (OAA) is formed in the mesophyll cells.
• It then forms other 4-carbon compounds like malic acid or aspartic acid in the mesophyll cells themselves, which are transported to the bundle sheath cells.
• In the bundle sheath cells, these C4 acids are broken down to release CO₂ and a 3-carbon molecule.
• The 3-carbon molecule is transported back to the mesophyll where it is converted to PEP again, thus, completing the cycle.
• The CO₂ released in the bundle sheath cells enters the C3 or the Calvin pathway, a pathway common to all plants.
• The bundle sheath cells are rich in the enzyme Ribulose bisphosphate carboxylase-oxygenase (RuBisCO), but lack PEPcase.
• Thus, the basic pathway that results in the formation of the sugars, the Calvin pathway, is common to the C3 and C4 plants.

Concept:

• Inspiration: It is the process of breathing air into the lungs.
• Expiration: It is the process of breathing air out of the lungs.

Explanation

• Tidal volume (TV): It is the amount of air delivered in and out of the lungs with each breath. It measures around 500ml.
• Residual volume (RV): It is the amount of air left in the lungs after maximum exhaling. It measures 1200ml.
• Vital capacity: It is the total amount of air that can be expired after a maximum inspiration.
• Inspiratory reserve volume (IRV): It is the extra forceful inspiration after a normal inhalation. It measures 3000 ml.

Other Related Points

• Expiratory reserve volume (ERV): It is the extra forceful expiration after a normal exhalation. It measures 1100ml.
• Inspiratory capacity: The maximum amount of inspiration after maximum expiration.
• Functional residual capacity: The volume remaining in the lungs after a normal, passive exhalation.
• Total lung capacity: It is the total amount of air lungs can hold.

Concept:

• Antifertility drugs are drugs that prevent pregnancy in women.
• These are also known as contraceptive agents.
• These are usually combinations of estrogen and progesterone.
• They affect the menstrual cycle and ovulation in a female.

Important Points

• Chloroxylenol -
  • It is a substituted phenol compound that acts as an antiseptic and disinfectant.
  • It has been widely used for disinfection of skin and surgical instruments.
• Norethindrone -
  • ​It is a form of progesterone that belongs to a class of medications called progestins.
  • It is used as an antifertility drug and prevents pregnancy.
  • It affects the cyclical changes in a female by inhibiting endometrium development.
• ​Tepineol -
  • Tepineol or terpineol is a monoterpenoid compound.
  • It is formed by modification of terpene with an additional alcohol group.
  • It can be used as insecticidal or fungicidal agent.
  • It is often found as a component of plant essential oils.
• Chloramphenicol -
  • It is a broad-spectrum antibiotic.
  • It inhibits protein synthesis in bacteria by binding with the ribosomes that take part in mRNA translation.

Therefore, Norethindrone is the antifertility drug among the given options.

• Golden rice is a genetically modified variety of regular rice, consisting of ß carotene, which is a precursor to Vitamin A.
• Golden rice is a part of the food fortification strategy, It is intended to produce a fortified food to be grown and consumed in areas with a shortage of dietary vitamin A.
• Deficiency of Vitamin A (Retinol) leads to a disease called Nyctalopia (night blindness) where the patient suffers from poor vision at night. Also, it may cause premature death in children below the age of 5.

Important Points

• Golden rice was developed by the International Rice Research Institute (IRRI).

Other Related Points

• Iron-deficiency anemia is the most common type of anemia, and it occurs when the body doesn't have enough of the mineral iron.
• Zinc is an essential element for growth and sexual development, its deficiency may lead to a variety of physical ailments like loss of appetite, unexplained weight loss, wounds that won’t heal.
• Obesity Is a disorder caused by the deposition of extra fat in the body, a person with a BMI higher than 25 is considered obese. It leads to higher health risks such as high blood pressure, diabetes, coronary artery disease.

Concept-

• A transgenic crop is a crop whose genes have been altered by manipulation. This crop is known as genetically modified crops (GM crops).
• GM plants can reduce reliance on chemical pesticides (pest-resistance crops).
  • For example- Some strains of Bacillus thuringiensis produce proteins that kill certain insects such as lepidopterans, coleopterans, etc.
  • Bt forms protein crystals during a particular phase of their growth. These crystals contain a toxic insecticidal protein.
  • The Bt toxin protein exists as inactive protoxins but once insects ingest the inactive toxin, it is converted into an active form due to the alkaline pH of the gut.
  • The activated toxin binds to the surface of midgut epithelial cells and creates pores that cause cell swelling and lysis and eventually cause the death of the insect.

Explanation-

• Bacillus thuringiensis produces crystal (Cry) protein. This Cry protein is toxic to the larvae of certain insects.
• Each Cry protein is toxic to a particular group of insects.
• The gene encoding cry protein is called the "cry gene".
• Cry protein isolated and introduced into several crops.
• cry gene is expressed by a crop that is usually resistant to the group of insects for which the concerned Cry protein is toxic.

So, The protein encoded by the gene cry3A controls the Colorado potato beetle.

Important Points

• The proteins encoded by the genes cryIAc and cryIIAb control the cotton bollworms.
• The proteins encoded by the genes cryIAb controls corn borer.

• The first transgenic cow was called Rosie and was produced in 1997.
• It was genetically engineered to produce human protein-enriched milk.
• This milk contained 2.4gms of human α-lactalbumin per litre of milk.
• Normal cow milk does not contain this protein.
• Thus, the milk from the transgenic cow was nutritionally more balanced for human babies than natural cow milk.

Important Points

• Transgenic animals refer to those that have had their genomes modified to possess and express a foreign gene.
• Reasons for production of transgenic animals:

1. Study of Physiology & Development -
   • Study of how genes and their regulation affects the physiological functioning of the body.
   • Complex growth factors like insulin can be studied.
2. Study of Diseases -
   • Transgenic animals serve as model organisms for studying human diseases.
   • They help in understanding the disease development process from genes.
   • They are also used for investigating new treatment methods.
   • Transgenic models exist for diseases like cancer, cystic fibrosis, rheumatoid arthritis and Alzheimer's.
3. Biological Products -
   • Many biological products that are essential for formulating medicines of use are often expensive.
   • These products can be obtained easily from transgenic animals.
   • This can be achieved by just introducing the gene responsible for the desired product into a suitable organism.
   • Example - Alpha-1 antitrypsin is a human protein that is required for emphysema treatment.
4. Vaccine Safety -
   • Transgenic mice can be used to test safety of vaccines before using for humans.
5. Toxicity Testing -
   • Transgenic animals can be made more sensitive to certain chemicals or drugs.
   • These animals are exposed to the toxic substances and their effects are then studied.

Other Related Points

• Dolly -
  • It was the first cloned sheep (1996).
  • It was also the first mammal to be cloned.
• Cumulina -
  • It was the first cloned mouse (1997).
• Noah -
  • It was the first cloned gaur (2000), which died within 2 days.
  • Gaur is an Indian bison that is listed as vulnerable in IUCN Red List.

• In Electron Transport Chain (ETC), the electrons are transferred through a series of carriers located in the inner mitochondrial membrane.
• The ETC in mitochondria comprises of different protein complexes that act as electron carriers:
  • Complex I - is NADH dehydrogenase that transfers electrons from NADH to Coenzyme Q (Ubiquinone).
  • Complex II - is succinate dehydrogenase that transfers electrons from succinate (TCA cycle intermediate) to coenzyme Q via FADH₂.
  • Complex III - receives the electrons from coenzyme Q, passes it from cytochrome b to cytochrome c and ultimately to complex IV.
  • Complex IV - is cytochrome oxidase that carries electrons from cytochrome c to molecular oxygen, reducing it to H₂O.
  • Complex V - is ATP synthase that has the F₀ and F₁ components that are responsible for driving the phosphorylation reaction of ADP to form ATP.

Explanation:

• The electron transfers are coupled with proton transport from the matrix outwards through the complexes I, III and IV.
• This creates a proton gradient across the inner mitochondrial membrane.
• As the proton concentration becomes lower in the matrix, the pH of the matrix increases.
• The proton gradient forms a pH gradient as well as electric potential, which forms an electrochemical gradient together and drives the protons back into the matrix from cytosol.
• The ATP synthase complex acts as a protein channel for the protons to move through as the membrane itself is impermeable to ions.
• As the protons move through the F0 component, the F1 component undergoes rotation that drives ATP synthesis.

Other Related Points

• NAD+ is oxidised - INCORRECT
  • ​NAD+ is an oxidising agent that accepts electrons.
  • Therefore, it gets reduced and NOT oxidised.
• ATP synthase pumps protons by active transport - INCORRECT
  • ​It is not active transport as the proton transfer takes place from higher to lower proton concentration.
  • Here, ATP synthase acts as a proton pump to produce ATP.

Concept:

• Cell division is defined as the process by which the mother cell divides into two daughter cells.
• There are two types of cell divisions:
  • Mitosis: Chromosomes are duplicated and distributed equally among the daughter cells.
  • Meiosis: Chromosome numbers are halved from diploid (2n) to haploid (n) number resulting in four haploid daughter cells.

Explanation:
Mitosis:

• Mitosis takes place in two stages - Karyokinesis (nuclear division) and Cytokinesis (cytoplasm division)
• Karyokinesis takes place in 4 sub-stages - Prophase, Metaphase, Anaphase, and Telophase

1. Prophase:
   • ​During this phase condensation of chromatin takes place.
   • Mitotic apparatus appear and the centromeres start migrating towards the two poles of the cell.
   • The nuclear membrane disappears.
2. Metaphase:
   • ​During this phase, chromosomes are highly condensed and can be seen under a microscope.
   • Chromosomes lie at the equatorial plate.
   • A mitotic spindle is fully formed
   • Centromeres are associated with chromatids.
3. Anaphase:
   • During this phase, the chromosomes start moving away from the equatorial plate into two groups.
   • Both groups contain one of the two chromatids of each original chromosome.
   • Thus the distribution of chromosomes in both the groups is equal.
   • This segregation of the chromosomes is initiated by a complex.​ The complex is called an anaphase-promoting complex (APC).
   • As a result, defects in the APC will hamper the segregation of the chromosomes. The two sister chromatids of the chromosome will not segregate.
4. Telophase:
   • ​The final stage of karyokinesis.
   • Chromosomes begin to uncoil.
   • The nucleolus and nuclear membrane begin to reappear.
   • Spindle fibers disappear.
   • Two daughter nuclei are formed in the cell.

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

The correct answer is tautonyms are not allowed in plants.

• Tautonyms are the species names in which specific epithet is the exact repeat of the generic name with/without transcribed symbol,
  • for example, Malus malus.
  • The tautonyms are never accepted by botanical nomenclature, although they are allowed in zoological nomenclature.

Other Related Points

• Herbarium sheet is a repository of preserved and labelled plant specimens that serve easy access and archival storage.
• The collected specimens are dried and pressed plants which are pasted on a sheet of paper together with an information label.
• The label including:
  • the plant's Latin name,
  • the origin of the collection,
  • the date of collection and
  • the name of the collector
• Herbarium sheets are all of the standard size, i.e., 29 cm x 41.5 cm (11.41” x 16.34”).
• Most of the Scientific names are derived from the Latin language.
• Genera Plantarum was written by the Bentham and Hooker.

Concept:

• Ecological pyramids are graphical representations of trophic systems in an ecosystem.
• Shape of pyramid can be upright (base broader than top), inverted (top broader than base) or variable.
• They are mainly of 3 types:

1. Pyramid of Number -
   • It is based on the number of individuals in each trophic level.
2. Pyramid of Biomass -
   • It is based on the quantitative biomass of organisms present in unit area (standing crop), for each trophic level.
3. Pyramid of Energy -
   • It is based on the energy content available at each trophic level.

• Trophic system refers to the system in which energy flows from one trophic level to another.
• Trophic level is the specific place in the food chain that is occupied by an organism based on their source of food.
• In an ecosystem, we find unidirectional flow of energy from Sun to producers to consumers.
• Ecosystems need a constant supply of energy to synthesize the molecules required in order to counteract the universal tendency of increasing disorderliness.
• In a grazing food chain, the energy trapped by the producer is passed on to the consumer or leads to death, which starts the detritus food chain and the energy is passed on to the decomposer.
• According to Lindeman's 10% Law, only 10% of the energy in a trophic level is transferred to the next, so that there can only be a limited number of trophic levels in each ecological pyramid.

Explanation:

• The pyramid of energy is always upright because of the 10% Law, meaning energy keeps decreasing at successive trophic levels.
• The unidirectional flow of energy gives stability to the ecosystem.
• Therefore, the pyramid of energy can never be inverted in a stable ecosystem.

Other Related Points

• The pyramid of number is upright in grassland ecosystem, while inverted in parasitic ecosystem and variable in forest ecosystem.
• The pyramid of biomass is usually upright, but can be inverted in pond ecosystem.

Concept:

• Heterospory - When there is a production of different types of spores in a single plant, this condition is called heterospory. The structure, formation, and functions of these spores differ.
• In pteridophytes, two different types of spores are present called Microspores and Megaspores.
• Microspores are male spores that are smaller in size and larger in number. Microspores are produced in Microsporangium.
• Megaspores are the female spores that are larger in size and smaller in number. Megaspores are produced in Megasporangium, these spores on germination produce the female gametophyte.

Explanation:

• The selaginella is a heterosporous pteridophyte i.e. it produces two different types of spores - the microspores & the megaspores.
• Other pteridophytes which show heterospory are - Isoetes, Marsilea, Salvinia, Azolla, Pilularia, etc.
• Pteridophytes showing homospory - Psilotum, Adiantum, and Pteris.

Other Related Points

The justification why the other options are incorrect:

• Marchantia is a liverwort belonging to the group Bryophyta. It has a sporophyte with foot, seta & capsule.
• Rhizopus is a fungus belonging to the group Phycomycetes. It reproduces by sporangiospores, not by conidia and ascospores.
• The Coralloid roots are the specialized roots found in cycas, not pinus.

Correct answer: 1)

Concept:

• Hormones are chemical messengers that are secreted in small quantities.
• Endocrine glands secrete hormones.
• Endocrine glands are ductless glands, and they secrete hormones directly into the bloodstream.

Explanation:

Option 1:

• Epinephrine also known as adrenaline is an amino acid derivative hormone. It is produced by the adrenal glands.
• It is known as an emergency hormone that is released during fear, fight, or flight. So, it is known as the 3F hormone.

Option 2:

• Ecdysone is a steroid hormone produced by some insects and by some other arthropods.
• Insects shed their exoskeleton as they grow, this is known as ecdysis or molting.
• Ecdysis is regulated by the hormone ecdysone.
• This hormone is secreted by corpora allata.

Option 3:

• Estriol is also a steroid hormone that works as a weak estrogen.
• It is one of the major endogenous estrogens.
• This hormone is important for pregnancy and also helps in labor and delivery.

Option 4:

• Estradiol is also a steroid hormone. It is also the type of estrogen involved in regulating the menstrual cycle and maintaining the reproductive system of females.
• This hormone is present in the female body throughout her reproductive years.

So, the correct answer is option 1.

The correct answer is Lysosome.

Explanation

• Lysosomes are present in animal cells.
• ​The lysosome word is made up of two Greek words ‘lyso” which means “split or break” and ‘soma’ which means ‘body’.
• It was first discovered by Belgian cytologist Christian de Duve in 1949.
• It contains digestive enzymes and is involved in the transport and degradation of various cellular metabolites.​

Other Related Points

• Cell walls are present in a plant cell.
• cell walls made of cellulose.
• A chloroplast is an organelle unique to plant cells that contain chlorophyll (which is what makes plants green) and is responsible for enabling photosynthesis to occur so that plants can convert sunlight into chemical energy.
• vacuoles help maintain water balance.

• Metamorphosis – is the process by which an animal undergoes a rapid change in form and structure after birth to form an adult that is significantly different from its juvenile stages.
• Retrogressive metamorphosis – refers to the type of metamorphosis that involves degenerative changes, meaning the juvenile phase lose some advanced characters in the process of development to become an adult with more primitive characters.
• It is a characteristic feature of the sub-phylum Urochordata or Tunicata.
• It is found in organisms like Herdmania, where larva shows chordate characters that are lost during development into the adult.

Explanation:

• Some changes involved during retrogressive metamorphosis in Herdmania:
  • Free-swimming active larva changes into sedentary inactive adult.
  • Larval tail with caudal fins shortens and disappears.
  • Nerve cord and notochord break down and are consumed by phagocytes.
  • Adhesive papillae disappear.
  • Larval sense organs, ocellus and otolith, are lost.
  • Sensory vesicles changes into adult cerebral ganglion.

Correct answer: (3)
Concept:

• Plant hormones or phytohormones are plant growth regulators that regulate the growth, development, reproduction, and death of the plant.
• There are different plant hormones such as ethylene, auxin, cytokinin, gibberellin, abscisic acid, etc.

Explanation:

• Ethylene is a gaseous hormone that regulates both growth and senescence.
• It promotes fruit ripening, senescence, abscission of plant organs (mainly leaves), breaks seed dormancy, etc.
• Abscisic acid is known as the stress hormone. It closes the stomata, causes abscission of plant organs, plant growth inhibitor, promotes dormancy, and works antagonistically to gibberellic acid/gibberellin. It increases the tolerance of plants to different stresses such as water stress.
• Cytokinin is another plant hormone that regulates plant growth and development. It promotes cell division, formation of leaves, formation of chloroplast, delays the process of senescence, etc.
• Gibberellin is a plant growth regulator that has many physiological effects. Gibberellin plays a role in flowering, increases the length of the internode, delays senescence, and promotes rosette formation in cabbages. One very important effect of gibberellin is on sugarcane. In sugarcane, it increases the length of the stem. It promotes maturity in juvenile conifers.
• Auxin is another plant hormone responsible for apical dominance. Apical dominance is a process where the growth of lateral roots is inhibited due to the presence of auxin. It also controls xylem differentiation. Indole acetic acid (IAA) is the naturally occurring auxin.

So, the correct answer is option 3.

The correct answer is The diaphragm is arched in normal expiration.

Explanation

• In normal expiration the diaphragm is arched.
• The diaphragm, located below the lungs, is the major muscle of respiration.
  • It is a large, dome-shaped muscle that contracts rhythmically and continually, and most of the time, involuntarily.
  • Upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarges.
  • The diaphragm is a thin skeletal muscle that sits at the base of the chest and separates the abdomen from the chest.
  • It contracts and flattens when you inhale.
  • This creates a vacuum effect that pulls air into the lungs.
  • When we exhale, the diaphragm relaxes and the air is pushed out of the lungs.

Concept

• RNA interference (RNAi) technology is used to silence a gene.
• After an infection, the infectious organism produces RNA in host cell to express toxins, produce more progeny, virus coat protein, etc.
• This RNA produced by the infectious agent can be silenced using a complementary dsRNA produced by the host.
• This dsRNA, being complementary will recognize and bind to the target RNA from nematode, bacteria or virus.
• To make a double-stranded RNA both sense and anti-sense RNA should be produced from the DNA.
• This method involves the silencing of a specific mRNA (from infection) due to a complementary dsRNA molecule (from host).
• The binding of dsRNA (host) prevents the translation of the mRNA (silencing) of the virus, bacteria or nematode.
• RNAi takes place in all eukaryotic organisms as a method of cellular defense.

Other Related Points
RNAi silencing for disease control

• A nematode Meloidegyne incognita infects the roots of tobacco plants.
• Nematode-specific genes were isolated and inserted into an Agrobacterium vectors
• Agrobacterium vectors were used to transfer those nematode-specific genes into the host plant.
• The introduction of DNA was such that it produced both sense and anti-sense RNA in the host cells.
• These two RNAs being complementary to each other formed a double-stranded (dsRNA).
• This dsRNA could bind to nematode mRNA produced after infection.
• That initiated RNAi and thus, silenced the specific mRNA from Meloidegyne incognita.

Concept:

• Vegetative reproduction is a method of asexual reproduction that occurs by roots, stems and leaves.
• It occurs without gamete formation and fertilization.

Explanation:

Option 1:

• Runner is also known as stolon.
• It grows horizontally along the ground and form aerial branches arising from nodes.
• For example, Strawberry, grasses, Cyanodo, Oxalis.

​Option 2:

• Offset is a common method of vegetative propagation in aquatic plants such as Pistia.
• A lateral branch with a short internode and each node containing a rosette of leaves and a tuft of roots is called an offset, which modifies the stem.

Option 3:

• Rhizome is a modified underground stem that grows horizontally.
• They develop from axillary buds. For example, ginger, bamboo etc.

Option 4:

• The suckers grow from the axil of the scale leaves that are present below the soil and it is not green in color.
• The sucker produces leaves and shoots from its upper side.
• Vegetative propagation in mint occurs by Suckers.

So, the correct answer is Option 4, Sucker.

The correct answer is Only (A), (B), and (C).
Explanation

• Biodiversity -
  • It refers to the diversity and variability of life on Earth.
  • The year 2010 has been declared the International Year of Biodiversity.
  • It is a natural resource, from which all our needs of life are met."

Other Related Points

• ​Causes of loss of biodiversity -
  • Destruction of natural habitats, hunting, rapid fishing, deforestation, increasing air pollution, water pollution, soil contamination, and global warming (or climate change).
  • All these factors are linked to overpopulation.
• Apart from these man-made causes, there are also some natural causes that lead to the loss of biodiversity.
• The National Biodiversity Authority (NBA) was constituted in 2003 by the Central Government under the "Biodiversity Act" of 2002.
  • The NBA is a statutory body and its headquarter is in Chennai.

Concept:

• Fruits are the mature fertilized ovary, where the fruit wall is formed from the ovary wall and seeds from ovules.
• A fruit consists of 2 parts:
  • Seed - It develops from the ovule.
  • Pericarp - It develops from the ovary wall and may differentiate into epicarp, mesocarp and endocarp layers.
• Fruits can be classified into 3 major types:
  • Simple - These develop from the ovary of a solitary pistil in a single flower. Example- Pea.
  • Aggregate - A group of separate fruits develop from carpels of one flower. Example- Magnolia.
  • Composite - They develop from complete inflorescence. Example- Banyan.

Important Points

• Drupe is a type of simple succulent fruit, which are also known as stone fruits.
• It is indehiscent and therefore, the seeds separate after the decay of the fleshy tissue around it.
• They are usually characterized by a stony hard endocarp and a middle fleshy mesocarp.
• The part of the fruit consumed is the mesocarp.
• Examples - Cherry, Peach, Almond, Plum, Coconut.

Explanation:

• The type of fruit of apple is known as pome.
• These fruits develop from the fleshy thalamus of syncarpous inferior ovary and are also called false fruits.
• Examples - Pear, Apple.

Hence, Apple is not a drupe type of fruit.