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(i) Nucleus: These organisms do not have well defined nucleus. DNA exists as a simple double stranded circular single chromosome called as nucleoid. Apart from the nucleoid they often show presence of extrachromosomal DNA which is small circular called plasmids. 

(ii) Reproduction: The mode of reproduction is asexual or with the help of binary fission or budding. Very rarely, sexual reproduction occurs by conjugation method. 

(iii) Nutrition: Majority are heterotrophic, parasitic or saprophytic in nutrition. Few are autotrophic that can be either photoautotrophs or chemoautotrophs.

1. Most of the members of kingdom fungi are saprophytes. 

2. They absorb food which is decomposed (digested) outside. 

3. Some are parasites or predators and some are symbiotic. 

4. In fungi, chloroplast is absent, thus they cannot synthesize their own food by photosynthesis. Due to this, fungi exhibit heteromorphic mode of nutrition.

(i) The DNA dependent RNA polymerase helps in DNA replication by catalysing the polymerisation in only one direction, i.e., 5′→3′. In bacteria, the RNA polymerase has co-factors β, β′, α, α′, ω and σ which catalyse the process. 

Transcription in Prokaryotes 

▪ In prokaryotes, the structural gene is polycistronic and continuous. 

▪ In bacteria, the transcription of all the three types of RNA (mRNA, tRNA and rRNA) is catalysed by single DNA-dependent enzyme, called the RNA polymerase. 

▪ In E. coli bacterium, the RNA polymerase has co-factors β, β′, α, α′ and ω along with σ (sigma) factor, to catalyse the process. 

▪ The transcription is completed in three steps: initiation, elongation and termination. 

▪ Initiation: σ (sigma) factor recognises the start signal and promotor region on DNA which then along with RNA polymerase binds to the promoter to initiate transcription. 

▪ Elongation: The RNA polymerase after initiation of RNA transcription loses the σ factor but continues the polymerisation of ribonucleotides to form RNA. 

▪ Termination: Once the RNA polymerase reaches the termination region of DNA, the RNA polymerase is separated from DNA–RNA hybrid, as a result nascent RNA separates. This process is called termination which is facilitated by a termination factor ρ (rho). 

▪ In prokaryotes, mRNA does not require any processing, so both transcription and translation occur in the cytosol. It can be said that transcription and translation are coupled together.

(ii) Transcription in Eukaryotes 

▪ The structural genes are monocistronic in eukaryotes. 

▪ The process of transcription is similar to that in prokaryotes. 

▪ It takes place in the nucleus. 

▪ Coding gene sequences called exons form the part of mRNA and non-coding sequence called introns are removed during RNA splicing. 

▪ In eukaryotes, three types of RNA polymerases are found in the nucleus: 

i. RNA polymerase I transcribes rRNAs (28S, 18S, and 5.8S). 

ii. RNA polymerase II transcribes the precursor of mRNA (called heterogeneous nuclear RNA or hnRNA). 

iii. RNA polymerase III transcribes tRNA, 5S rRNA and snRNAs (small nuclear RNAs).

Nutrition: The fungi exhibit heterotrophic mode of nutrition and most of the members are saprophytes and absorb food which is decomposed (digested) outside. Some are parasitic or predators.

Ascomycetes:

1. These are commonly called as sac fungi.

2. These are multicellular. Rarely they are unicellular (e.g. Yeast).

3. Hyphae are branched and septate.

4. They can be decomposers, parasites or coprophilous (grow on dung).

5. Some varieties of this class are consumed as delicacies such as morels and truffles.

6. Neurospora is useful in genetic and biochemical assays. e.g.

Aspergillus, Penicillium, Neurospora, Claviceps, Saccharomyces (unicellular ascomycetes).

Euglenoids: 

1. They lack cell wall but have a tough covering of proteinaceous pellicle. 

2. Pellicle covering provides flexibility and contractibility to Euglena.

3. They possess two flagella, one short and other long. 

4. They behave as heterotrophs in absence of light but possess pigments, similar to that of higher plants, for photosynthesis.

General characters of Kingdom Fungi: 

1. Type of organisms: It is a unique kingdom of eukaryotic heterotrophic organisms, showing extracellular digestion. They may be unicellular or multicellular and filamentous. These are commonly found in warm and humid places. 

2. Nucleus: The cells may be multinucleate or uninucleate. 

3. Body: Multicellular organisms consist of a body called mycelium in which a number of thread or fibre-like structures called hyphae are present. The hyphae may be with septa (septate) or without septa (aseptate). The non-septate multinucleated hyphae are called coenocytic hyphae. 

4. Cell wall: The cell wall in fungi is composed of chitin or fungal cellulose. 

5. Cell organelles: The fungi contain well organized membrane bound cell organelles except the chloroplasts. 

6. Nutrition: The fungi exhibit heterotrophic mode of nutrition and most of the members are saprophytes and absorb food which is decomposed (digested) outside. Some are parasitic or predators. 

7. Reproduction: They reproduce both sexually as well as asexually. Asexual reproduction takes place by fragmentation, fission and budding. 

8. Some fungi are symbiotic. These fungi either live with algae as lichens or as mycorrhiza in association with roots of higher plants.

Deuteromycetes: 

• It is a group of fungi which are known to reproduce only asexually. 
• They are commonly called imperfect fungi. 
• They are mainly decomposers, while few are parasitic, e.g. Alternaria.

Fungi are classified into four types on the basis of their structure, mode of spore formation and fruiting bodies as follows: 

1. Phycomycetes: Members of this class are commonly called as algal fungi. 

These are consisting of aseptate coenocytic hyphae. 

They grow well in moist and damp places on decaying organic matter as well as in aquatic habitats or as parasites on plants. 

e.g. Mucor, Rhizopus (bread mold), Albugo (parasitic fungus on mustard).

2. Ascomycetes: 

These are commonly called as sac fungi. 

These are multicellular. Rarely they are unicellular (e.g. Yeast).

Hyphae are branched and septate. 

They can be decomposers, parasites or coprophilous (grow on dung).

Some varieties of this class are consumed as delicacies such as morels and truffles. 

Neurospora is useful in genetic and biochemical assays. 

e.g. Aspergillus, Penicillium, Neurospora, Claviceps, Saccharomyces (unicellular ascomycetes). 

3. Basidiomycetes:

These are commonly called as club fungi. 

They have branched septate hyphae. e.g. Agaricus (mushrooms), Ganoderma (bracket fungi), Ustilago (smuts), Puccinia (rusts), etc. 

4. Deuteromycetes: 

It is a group of fungi which are known to reproduce only asexually. They are commonly called imperfect fungi. 

They are mainly decomposers, while few are parasitic, e.g. Alternaria.

The interaction between clown fish and sea anemone is called commensalism. The clown fish gets protection from predators which stay away from the stinging tentacles of sea anemone. The sea anemone does not appear to derive any benefit by hosting the clown fish.

Sea anemone has stinging tentacles and the clown sh lives among them, In this interaction the sh get protection from predators which stay away from the stinging tentacles but sea anemone does not derive any benefit or harm by hosting the clown fish.

Commensalism

Correct answer is (b) Commensalism

Correct answer is (a) Biotic factor

Correct answer is (a) Biotic community

1. Orchid is an epiphyte. It gets the support from the mango tree. But it does not cause any harm to the mango tree. 

2. Mango tree does not derive any benefit from this association. Therefore, this interaction is of type of commensalism.

It is an example of commensalism, where the orchid gets space (benefited) but the mango tree is neither benefited nor harmed.

Snail and fish.

The monocot plants such as cereals and pulses and also mango are commercially important cash crops. Therefore, in order to obtain profitable harvest, different reproductive strategies are adopted.

When the resources in the habitat are unlimited, each species has the ability to grow in number. Here the population grows in an exponential or geometric fashion. dN/dt = rN

Limited resources leads to competition between individuals and the ‘fittest’ individual will survive and reproduce. This is called logistic growth

\(\frac{dN}{dt}\) = rN\(\frac{(K-N)}{K}\)

Correct option: (C) proteins and nucleotides

The genetic material in viruses is either DNA or RNA and surrounded by a protein coat called Capsid.

Technique of in vitro regeneration of whole plant by growing any plant part called explant in culture medium under aseptic condition. 

Includes following methods: 

1. Callus culture: Cell division in explant form an unorganized mass of cell called callus. 

2. Suspension culture: Involves small group of cells suspended in a liquid media. 

3. Meristem Culture – Apical shoot meristem is used as explant & support multiple shoot development. 

4. Embryo Culture: Excision of young embryos from developing seeds & culture in nutritional media. 

5. Anther culture: Production of haploid plant species by desired anther cultured in suitable medium. 

Correct option: (D) Both (A) and (C)

Correct option: (B) non-septate

Correct option: (B) They make the environment more alkaline

Correct option: (D) All the three statements are true

Genetic variation in plants regenerated from a single culture is used to develop several useful varieties eg., Short duration sugarcane, Rust resistant wheat. 

Uses: 

(a) Rapid clonal multiplication 

(b) Production of virus free plants 

(c) Production of transgenic plants 

(d) Germplasm collection 

• Tissue culture technique used for rapid vegetative multilication of ornamental plants and fruit trees by using small explants.
• Micropopagation is done by shoot meristem culture & somatic embryogeny. It results in genetically identical plants & used widely in forestry & floriculture. 

In this method, hybridization of different species could produce variants of economic value as follows: 

• Isolation of desired single cells. 
• Digestion of cell wall by pectinase & cellulase enzyme for exposure of protoplast.
• Fusion of protoplast by Polyethylene glycol(PEG).
• Hybrid protoplast culture resulting in desired variety of plant eg., Pomato is obtained by somatic hybrid of potato and tomato.

Correct option: (B) rhizines

Correct option: (A) non scientific

(1) Walter, Sutton – Chromosomes of grasshopper.

(2) Mclyn McCarthy – DNA is genetic material.

Correct option: (D) Cyanobacteria

In anaerobic sludge digester, the anaerobic bacteria the methanogen digest the flocks of bacteria and fungi in activated sludge and produce methane along with H₂O and CO₂ i.e., biogas which is a source of energy as it is inflammable.

(A) ग्रांट एनिकट

सही उत्तर है कावेरी

1. Cockroach has a pair of salivary glands which secrete saliva. 

2. Each gland has a salivary duct. 

3. Both the ducts unite to form a common salivary duct.

Wings: Forewings and hindwings form the two pair of wings present on the dorsal side. Forewings are the first pair of dark, opaque, thick, leathery wings. Hindwings are thin, broad, membranous delicate and transparent. They are attached to tergum of metathorax. 

Functions: Forewings are protective in function and hindwings are helpful in flight, thus are called true wings.

सही उत्तर है सतलुज

भाखड़ा-नांगल योजना का लाभ पंजाब, हरियाणा और राजस्थान को मिलता है ।

Thorax: Thorax is made up of three distinct segments – prothorax (anterior segment), mesothorax and metathorax (posterior segment). Ventrally, the thorax bears three pairs of walking legs, one at each segment. Dorsally, the thorax bears two pairs of wings attached to mesothoracic and metathoracic segment of the body, 

a. Legs: Three pairs of walking legs are present on the ventral side. Each leg is formed of five podomeres namely coxa, trochanter, femur, tibia and tarsus. Tarsus is the last segment and it is made up of five movable segments or tarsomeres. The last tarsomere bears a pair of claws and cushion like arolium helpful in clinging.

सही विकल्प है (D) 50%

सही विकल्प है (D) सतलुज

The correct answer is (C) In cockroach, heart has 22 chambers.

The correct answer is (C) 16

The structural and functional unit of eye of cockroach. Ommatidia

1. Oviduct or fallopian tubes.

2. Penis.

External fertilisation

1. The fusion of sperm and egg occurs outside the female body in external fertilisation.

2. It needs water or else the gametes will dry out and die.

3. Wastage of gametes is higher.

4. Mostly frogs (amphibians) and fishes shows external fertilisation.

Internal fertilisation

1. The fusion of sperm and egg occurs inside the female body in internal fertilisation.

2. It does not need water.

3. Wastage of gametes is lower.

4. Mostly reptiles mammals, birds and insects show internal fertilisation.