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Answer (A) Papaver somniferum

Answer (B) PCR

Answer (A) Haploid

Amplification of gene for interest may be done by PCR.

Term Homlogous was introduced by Richard Owen. The organs which have the same fundamental structure but the different in functions are called Homologous organs. These organs follows the same basic plan of organisation during their development. But in adult condition, these organs are modified to perform different functions an adaptation to different environments. The homologus organs are a result of divergent evaluation. Homology indicates common ancestry.

Examples:- Fore-limbs of whole, cheetah and man represent the similar structure of bones like Humerus, Redulna etc.

Analogous organs are those organs which have similar functions but are defferent in their structural details and origin. Such organs are the result of convergent evolution.

Examples- Wings of insects and wings of birds. Fins of fishes and Flippers of whales.

DNA is a genetic material of all organism except RNA viruses.

(i) DNA is made up of two polynucleotide chains. The unit of polycleotide is nucleotide. Nucleotide is made up of nitrogenoces bases, pentose sugar and phosphate.

(ii) The bases are of two types- pyrines and pyrimidines.

(a) Purines- Adenine (A) and Guanine (G)

(b) Pyrimidines- Cytosine (C) and Thymine (T)

(iii) Sugar is in the form of dexyribose

(iv) Phosphate is in the form of orthophosphoric acid.

Chemical linkage:-

The base is attached to the number carbon of the sugar. The phosphate group is attached to the number 5-carbon of one sugar and number 3-carbon of sugar of adjacent nucleotide with loss of one molecule of water. This bond is called phosphocliester bond which forms polynucleotide.

Double helix:-

(i) On the basis of works by chargaff and Wilkins, Watson and crick proposed double helix model of DNA. According to this model, DNA is made up of two helical polynucleotides. Both relices are right handed and coiled around the same axis to form a double helix.

(ii) The basis are on the inside of helix in pairs arranged in such a fashion that purine of one chain pairs with pyrimmidine of another chain (A -T) and (G - C).

(iii) The pair between bases is faciliated by hydrogen bonding. The hydrogen bonds between A = T is two and between G ≡ C is three. That is why DNA with high G - C content has mas melting point.

(iv) The distance between two nucleotides is 3.4 Å. One turn of the helix convers a distance of 34 Å, hence 10 base pairs are accommodated per turn of the helix. Since one turn of the helix involves 360° it is evident that one-base-pair at an angle of 36°. These two helices are so coiled as to generate successively a major and a minor groove on each side.

(v) The diameter of double helix is about 20 Å.

(vi) The two helices of DNA run anti-parallel i.e. one strand in 5'-3' direction and another in 3'-5' direction. This is necessary to present pair of bases in such position to each other as to make possible formation of H-bond.

Cross pollination- It is the transfer of pollens from one flower to the stigma of another flower belonging to genetically different plant. Cross pollination can occur only with the help of external agents called pollinating agents or agencies.

The various agencies of cross pollinations are

(i) Wind (ii) Water (iii) Animals

Answer (d) Wind

Gametes are usually Haploid.

Answer (A) Product

Taichung is a variety of Rice.

(A) Product.

• Extension of agriculture 
• Constraction of roads, railways and industries 
• Establishment human settlements and 
• Mining activities

Effects of deforestration:

• Soil degradation and soil erosion. 
• Destruction of natural habits of wild life and loss of biodiversity. 
• Climatic changes such as desertification, global warming and etc.

Remedies to control the deforestration:

• Prevention of human settlements in forest areas. 
• Check on expansion of agriculture. 
• Prohibition of setting up of industries in forest areas. 
• Controlling on irresponsible cutting down timber trees. 
• Control of over grazing on forest region. 
• Controlling of mining activity in forest lands. 
• Limitation on construction of Large dams in forest areas.

Answer:  kilogram (kg)

Convergent evolution: Different structures evolving for the same function. Eg: Analogous organs 

 Divergent evolution: Same structure developed in different directions for different needs. Eg: Homologous organs

Answer: CaF₂+H₂SO₄ →CaSO₄ +2HF

In this reaction, the oxidation number of Ca,H,S and O are not changed (oxidation number not changed means it is not a redox reaction). 

Hence, H₂SO₄ is not acting as an oxidising agent and reducing agent.

User friendly,easily available,effective

(a) To delay pregency. 

(b) To space children.

(1)    LNG-20

(2) Zoospores are absent in Mucor and Rhizopus

(3) In the pressure flow hypothesis, osmotic pressure at sink must be reduced 

(4) Genotype of Husband:- I^AI^B 

     Genotype of Wife:- I^AI 

The possible Genotypes are:- I^AI^A, I^AI, I^AI^B   I^BI 

Possible Phenotypes:- A(I^AI^A, I^AI), B(I^BI), AB(I^AI^B) 

Therefore, there are 4 Genotypes and 3 Phenotypes. 

(5) They are exotic species

(6) The common technique most used for induced breeding in fishes is Hypophysation

(7) No, Buna- n is a non biodegrade substance

(8) Yes, Sunflower is an example of cypsella

(9) The statement is true, as Pusa A-4 is an insect-resistant variety of okra or bhindi. 

(10) Dumb-bell shaped guard cells are found in Sugarcane and Cereals.  

Reproductive related problems are following:– 

 (i) Pregnancy 

(ii) Delivery 

(iii) Sexually transmitted disease 

 (iv) Abortion 

(v) Contraception 

(vi) Menstrual problems (Any four) 

Gregor Mendel, conducted hybridisation experiments on garden peas for seven years (1856-1863) and proposed the laws of inheritance. During Mendel’s investigations into inheritance patterns it was for the first time that statistical analysis and mathematical logic were applied to problems in biology. His experiments had a large sampling size, which have greater credibility to the data that he collected. Also, the confirmation of his inferences from experiments on successive generations of his test plants, proved that his results pointed to general rules of inheritance rather than being unsubstantiated ideas. 

Mendel selected only pea plant for his experiment due to presence of many types of contrasting characters, like- 

(i) Round and wrinkled seed 

(ii) Yellow and green seed 

(iii) Violet and white flower 

(iv) Inflated and constricted pod 

(v) Green and yellow pod 

(vi) Axillary and terminal flower 

(vii) Tall and dwarf plant 

Mendel investigated characters in the garden pea plant that were manifested as two opposite traits which allowed him to setup a basic frame work of rules governing inheritance. Mendel conducted such artificial pollination/cross pollination experiments using several true breeding pea lines. 

Advantages of selecting pea plants for experiment by Mendel:– 

(c) Due to short height of pea plant, it was easy to do experiment on that. 

(d) Pea plant had a short life cycle so that results could be had within a year. 

(e) Pea plant produced many seeds in one generators which helped in drawing correct conclusions. 

(f) Artificial cross-pollination could be easily achieved because androecium and gynoecium were completely enclosured.

(g) Pea plants having each of the seven characters he selected were readily available.

(h) Mendel took only one character at one time for his experiment. 

(i) Pea plants are self pollinated and pure.

Gene therapy is a collection of methods that allows correction of a gene defect that has been diagnosed in a child/embryo. Here genes are inserted into a person’s cells and tissues to treat a disease. Correction of a genetic defect involves delivery of a normal gene into the individual or embryo to take over the function of and compensate for the non-functional gene.

The first clinical gene therapy was given in 1990 to a 4-year old girl with adenosine deaminase (ADA) deficiency. This enzyme is crucial for the immune system to function. This disorder is caused due to the deletion of the gene for adnesine deaminase. 

In some children ADA deficiency can be cured by bone marow transplantation; in others it can be treated by enzyme replacement therapy, in which functional ADA is given to the patient by injection. But the problem with both of these approaches that they are not completely curative. As a first step towards gene therapy, lymphocytes from the blood of the patient are grown in a culture outside the body. A functional ADA cDNA (using a retroviral vector) is then introduced into these lymphocytes, which are subsequently returned to the patient. However, as these cells are not immortal the patient requires periodic infusion of such genetically engineered lymphocytes. However, if the gene isolate from marrow cells producing ADA is introduced into cells at early embryonic stages, it could be a permanent cure.

T-cells attack directly and destroy antigens. In the process, these cells move to the site of invasion and produce chemicals that attract phagocytes and stimulate them so that they can feed more vigorously on antigens. They also produce substances that attract other T-cells. 

Transfer of pollengrains after sheding from the anther to the stigma of the carpel is called pollination. 

Pollination in flowering plants occurs by two methods- (1) Self Pollination and (2) Cross Pollination. 

(1) Self Pollination – Self pollination involves the transfer of pollengrains from the anther of the flower to the stigma of the same flower or another flower of the same plant. 

(2) Cross Pollination – Cross pollination involves the transfer of pollengrains from the flower of one plant to the stigma of the flower of another plant. 

Varied means of cross pollination in plants are– 

(a) Dicliny – Cross pollination always occurs when the plants are unisexual and dioecious. Ex-Papaya 

(b) Self Sterility – When the stigma of the gynoecium of a flower is not pollinated by pollengrains of the same flower. Ex-Pea, Potato etc.

(c) Dichogamy – When maturity of male and female parts of a bisexual flower occurs in different times. It is of two types. (i) Protogyny (wen gynoecious matures first. Ex-Banyan) and (ii) Protandry (When androecium matures first. Ex-Maize) 

(d) Herkogamy – In some flowers physical barrier present between anther and stigma which avoid self pollination. Ex- Calotropis 

(e) Heterostyly – The flowers of some plants have different lengths of stamens and styles so that self pollination is not possible. Ex-Primula, Oxalis etc.

Biodiversity is the variation of life at all levels of biological organization. In other words variability found in different forms of life like plants, animals and microorganisms and in their genes are called as biodiversity. It voluntarily integrates terresterial, aquatic and ecosystem diversity.  

There are three basic components of biodiversity:– (1) Genetic diversity, (2) Species diversity and (3) Ecological diversity. 

(d) Genetic diversity – Genetic diversity is related to the variations of genes within species. A single species might shows high diversity at the genetic level over its distributional range. For example, genetic variations shown by the medicinal plant Rauwolfia vomitoria growing in different Himalayan ranges might be in terms of the potency and concentration of the active chemical (reserpine) that the plant produces. India has more than 50,000 genetically different strains of rice, and 1,000 varieties of mango. 

(e) Species diversity – The diversity at the species level is called species diversity. For example, the Western Ghats have a greater amphibian species diversity than Eastern Ghats. Similarly, taking example of plants, brinjal (Solanum melanogena), Potato (Solanum tuberosum) and tomato (Solanum lycopersicon) belong to the same genus Solanum but they all too differ at the species level. 

(f) Ecological diversity – The diversity at the ecosystem level is called ecological diversity. It is related to the different types of ecosystems, e.g., terrestrial (Deserts, rain forest, grass land, etc.) and aquatic (rivers, ponds, lakes, sea, etc.) ecosystems. 

Ecological diversity is of three types – Alpha (α), Beta (β) and Gamma (γ) diversity 

(i) Alpha diversity – It refers to the diversity of those organism which belongs to same community and habitat. 

(ii) Beta diversity – Diversity between diferent communities of same habitat is called beta diversity. If there is more heterogeneity in the habitats in a region or more dissimilarity between communities, there will be more beta diversity. 

(iii) Gamma diversity – Diversity at landscape level is called gamma diversity. It envolves both types of diversity – alpha and beta. It refers to the diversity of the habitats in the whole geographical region.

Milky water of green coconut is liquid endosperm.

Three important components of biodiversity are 

(a) Genetic Biodiversity 

(b) Species Biodiversity 

(c) Ecological Biodiversity 

During the last few decades, there has been a vast change in the instructional process followed by teachers in the classroom.

• Initially, instruction was based on the behaviouristic approach which has shifted to humanistic and more recently is focused on the constructivist approach.
• But still, in many classrooms across the globe, teachers more often use teacher-centric methods, especially where the size of the classroom is more than fifty. In teacher-centric classrooms, all the instructional activities and procedures are under the control of the teacher.
• Teacher plans prepare and conduct the teaching-learning process including the kind of learning experiences to be provided to learners, and activities to be carried out by the learners. Though it is teacher-controlled, the teacher can bring flexibility into the classroom through learners’ participation.

There are various teacher-centered instructional methods:

Lecture Method:

• The Lecture Method: the teacher instructs or gives a lecture on a topic for most of the complete time in the period.
• The teacher provides information, concepts, facts, events, theories, laws, principles, etc.
• Students are passive listeners. Their activities during the lecture period, at best, are taking down some notes and responding to occasional questions of the teacher.

Demonstration Method:

• The demonstration method is teacher-centered as the teacher demonstrates the pictures/ charts/models/experiments and explains the principles, concepts involved in these demonstrated materials or processes. The students observe the demonstration shown by the teacher and some of them participate in answering the questions asked by the teacher and draw conclusions.

Individualized instruction:

• In Individual Instruction method as a teacher, we are more active in teaching and instructing while the students are more passive and acting in a limited way only when they are directed by us as teachers are individual.

Learner-centred Method:

Modelling:

• Modelling can be used in all stages to help learn a new skill, undertake a task more effectively in terms of the success criteria, develop thinking skills, and thought processes etc.
• Task modelling occurs when the teacher demonstrates a task students will be expected to do on their own.

Hence, modelling is not teacher-centred instruction.

The correct answer is 'falling-rising'.

•  Intonation refers to the pattern of rising and fall (that is, sliding in between) in the level (that is, the 'pitch') of the voice.
•  Falling and rising tones are the main two patterns of intonation.
  • Rising intonataion- We tend to use this rising intonation pattern when we’re asking questions. So the pitch of our voice tends to go up.
  • Falling intonataion- A falling intonation or downward intonation pattern, would simply mean that the pitch of the voice drops down; this downward intonation tends to be used for exclamation, statements and commands and at the end of our sentences.
• ​Fall-rise intonation describes how the voice falls and then rises. We use fall-rise intonation at the end of statements when we want to say that we are not sure, or when we may have more to add
• ​Here, In 'He has passed with distinction in English, however ...'  initially pitch is falling to English and further the speaker wants to add more in the statement 
   

​​​​Hence, we can conclude that the appropriate intonation for the sentence- He has passed with distinction in English, however, is falling-rising

• Intonation is a feature of pronunciation, and it is common in all languages.  

• Other features of pronunciation include stress, rhythm, connected speech, and accent. 
• ​The patterns of variation of the pitch of the voice i.e. the way in which the pitch varies constitute the intonation of a language.
  • Each language has its own intonation patterns. The falling tone marked thus (\) and rising tone is marks thus(/), for example
    • We should buy a \car.
    • Should we buy a /car?

Student 1: Incorrect response

Student 2: Incorrect response

Intonation is the melodic pattern and primarily a matter of variation in the pitch level of the voice, but in the English language, stress, and rhythm are also involved. They convey differences of expressive meaning (e.g., surprise, anger, wariness).

• They serve the grammatical function, distinguishing one type of phrase or sentence from another. 
• In a listening-speaking assessment activity
  • Teacher: Have you watched any English films lately? Tell your friend about it.
  • Student 1: Of course. Especially animations.
  • Stude nt 2: Me too. I like them a lot.

• The responses given by students are incorrect responses because as after listening to the instructions, the speaker needs to share the instances or experiences with the friend using intonations. Here, both the students are giving responses to the teacher instead of asking and telling each other. Which leads the teacher to assess their speaking and listening skills.

​Hence, we can conclude that student 1: incorrect response and student 2: incorrect response. 

Those individuals which survive and reproduce in their respective environment are called fit.

 Those individuals which survive and reproduce in their respective environment are called fit.

Ag₂Cro₄ → 2 Ag⁺ + cro₄^-2

using law at mass action

K = \(\frac {[Ag^+]^2[Cro_4^{-2}}{Ag_2Cro_4}\)

= K [Ag₂Cro₄] = [Ag⁺]² [Crp₄^-2]

= Ksp = [Ag⁺]² [Cro₄^-2] (Ksp = K [Ag₂Cro₄])

Let say solubility of Ag₂Cro₄ = S

M = 8.0 x 10^-5m

∴ Ksp = [2s]² [s]

Ksp = 4s³

Ksp = 4 x (8.0 x 10^-5)³

Ksp = 2048 x 10^-15

Ksp = 2.048 x 10^-12

Hence the solubility product at Ag₂Cro₄ will be 2.048 x 10^-12

A glass tube made of pyrex is called a heating tube

Frost is the solid state of water.

A molecule of nitrogen consists of two atoms of element nitrogen only.

A compound is formed by a combination of at least two elements.

In solids, the molecules are closely packed and retain their shape.

Water is fluid.